Bernard Marty

@article{Bekaert_etal2023,

title = {Last glacial maximum cooling of 9 textdegreeC in continental Europe from a 40 kyr-long noble gas paleothermometry record},

author = {D. V. Bekaert and P. H. Blard and Y. Raoult and R. Pik and R. Kipfer and A. M. Seltzer and E. Legrain and B. Marty},

doi = {10.1016/j.quascirev.2023.108123},

year  = {2023},

date = {2023-01-01},

journal = {Quaternary Science Reviews},

volume = {310},

pages = {108123},

abstract = {The Last Glacial Maximum (LGM; \^{a}`u26--18 kyr ago) is a time interval of great climatic interest characterized by substantial global cooling driven by radiative forcings and feedbacks associated with orbital changes, lower atmospheric CO2, and large ice sheets. However, reliable proxies of continental paleotemperatures are scarce and often qualitative, which has limited our understanding of the spatial structure of past climate changes. Here, we present a quantitative noble gas temperature (NGT) record of the last \^{a}`u40 kyr from the Albian aquifer in Eastern Paris Basin (France, \^{a}`u48textdegreeN). Our NGT data indicate that the mean annual surface temperature was \^{a}`u5 textdegreeC during the Marine Isotope Stage 3 (MIS3; \^{a}`u40--30 kyr ago), before cooling to \^{a}`u2 textdegreeC during the LGM, and warming to \^{a}`u11 textdegreeC in the Holocene, which closely matches modern ground surface temperatures in Eastern France. Combined with water stable isotope analyses, NGT data indicate $delta$D/NGT and $delta$18O/NGT transfer functions of +1.6 textpm 0.4texttenthousand/textdegreeC and +0.18 textpm 0.04texttenthousand/textdegreeC, respectively. Our noble-gas derived LGM cooling of \^{a}`u9 textdegreeC (relative to the Holocene) is consistent with previous studies of noble gas paleothermometry in European groundwaters but larger than the low-to-mid latitude estimate of 5.8 textpm 0.6 textdegreeC derived from a compilation of noble gas records, which supports the notion that continental LGM cooling was more extreme at higher latitudes. While an LGM cooling of \^{a}`u9 textdegreeC in Eastern France appears compatible with recent data assimilation studies, this value is greater than most estimates from current-generation climate model simulations of the LGM. Comparing our estimate for the temperature in Eastern France during MIS3 (6.4 textpm 0.5 textdegreeC) with GCM outputs presents a promising avenue to further evaluate climate model simulations and constrain European climate evolution over the last glacial cycle.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ardoin_etal2022,

title = {The end of the isotopic evolution of atmospheric xenon},

author = {L. Ardoin and M. W. Broadley and M. Almayrac and G. Avice and D. J. Byrne and A. Tarantola and A. Lepland and T. Saito and T. Komiya and T. Shibuya and B. Marty},

doi = {10.7185/geochemlet.2207},

year  = {2022},

date = {2022-01-01},

journal = {Geochemical Perspectives Letters},

volume = {40},

abstract = {Noble gases are chemically inert and, as such, act as unique tracers of physical processes over geological timescales. The isotopic composition of atmospheric xenon, the heaviest stable noble gas, evolved following mass-dependent fractionation throughout the Hadean and Archaean aeons. This evolution appears to have ceased between 2.5 and 2.1 Ga, around the time of the Great Oxidation Event (GOE). The coincidental halting of atmospheric Xe evolution may provide further insights into the mechanisms affecting the atmosphere at the Archaean-Proterozoic transition. Here, we investigate the isotopic composition of Xe trapped in hydrothermal quartz from three formations around the GOE time period : Seidorechka and Polisarka (Imandra-Varzuga Greenstone Belt, Kola Craton, Russia) with ages of 2441thinspacetextpmthinspace1.6 Ma and 2434thinspacetextpmthinspace6.6 Ma, respectively, and Ongeluk (Kaapvaal Craton, South Africa) dated at 2114thinspacetextpmthinspace312 Ma (Ar-Ar age) with a host formation age of 2425.6thinspacetextpmthinspace2.6 Ma (upper bound). From these analyses we show that Xe isotope fractionation appears to have ceased during the time window delimited by the ages of the Seidorechka and Polisarka Formations, which is concomitant with the disappearance of mass-independent fractionation of sulfur isotopes (MIF-S) in the Kola Craton. The disappearance of Xe isotope fractionation in the geological record may be related to the rise in atmospheric oxygen and, thus, can provide new insights into the triggering mechanisms and timing of the GOE.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Okazaki_etal2022,

title = {Noble gases and nitrogen in samples of asteroid Ryugu record its volatile sources and recent surface evolution},

author = {R. Okazaki and B. Marty and H. Busemann and K. Hashizume and J. D. Gilmour and A. Meshik and T. Yada and F. Kitajima and M. W. Broadley and D. Byrne and E. and F\"{u}ri},

doi = {10.1126/science.abo0431},

year  = {2022},

date = {2022-01-01},

journal = {Science},

number = {8},

pages = {abo0431},

abstract = {The near-Earth carbonaceous asteroid (162173) Ryugu is expected to contain volatile chemical species that could provide information on the origin of Earth’s volatiles. Samples of Ryugu were retrieved by the Hayabusa2 spacecraft. We measure noble gas and nitrogen isotopes in Ryugu samples, finding they are dominated by pre-solar and primordial components, incorporated during Solar System formation. Noble gas concentrations are higher than those in Ivuna-type carbonaceous (CI) chondrite meteorites. Several host phases of isotopically distinct nitrogen have heterogeneous abundances between the samples. Our measurements support a close relationship between Ryugu and CI chondrites. Noble gases produced by galactic cosmic rays, indicating textasciitilde5 Myr exposure, and from implanted solar wind, record the recent irradiation history of Ryugu after it migrated to its current orbit.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Almayrac_etal2022,

title = {The EXCITING experiment exploring the behavior of nitrogen and noble gases in interstellar ice analogs},

author = {M. G. Almayrac and D. V. Bekaert and M. W. Broadley and D. J. Byrne and L. Piani and B. Marty},

doi = {10.3847/PSJ/ac98b0},

year  = {2022},

date = {2022-01-01},

journal = {The Planetary Science Journal},

volume = {3},

pages = {252},

abstract = {Comets represent some of the most pristine bodies in our solar system and can provide a unique insight into the chemical makeup of the early solar system. Due to their icy volatile-rich nature, they may have played an important role in delivering volatile elements and organic material to the early Earth. Understanding how comets form can therefore provide a wealth of information on how the composition of volatile elements evolved in the solar system from the presolar molecular cloud up until the formation of the terrestrial planets. Because noble gases are chemically inert and have distinct condensation temperatures, they can be used to infer the temperatures of formation and thermal history of cometary ices. In this work, we present a new experimental setup called EXCITING to investigate the origin and formation conditions of cometary ices. By trapping nitrogen and noble gases in amorphous water ice, our experiment is designed to study the elemental and isotopic behavior of volatile elements in cometary ice analogs. We report new results of noble gas and nitrogen enrichment in cometary ice analogs and discuss the limitations of the experimental conditions in light of those supposed for comets. We show that forming ice analogs at \^{a}`u70 K best reproduce the noble gas and N2 abundances of comet 67P/Churyumov--Gerasimenko, considering a solar-like starting composition. This formation temperature is higher than previous estimates for cometary ices and suggests that the formation of cometary building blocks may have occurred in the protosolar nebula rather than in the colder molecular cloud.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Tachibana_etal2022,

title = {Pebbles and sand on asteroid (162173) Ryugu : In situ observation and particles returned to Earth},

author = {S. Tachibana and H. Sawada and R. Okazaki and Y. Takano and K. Sakamoto and Y. N. Miura and C. Okamoto and Yano and S. Yamanouchi and P. Michel and Y. Zhang and S. Schwartz and F. Thuillet and H. Yurimoto and T. Nakamura and T. Noguchi and H. Yabuta and H. Naraoka and A. Tsuchiyama and N. Imae and K. Kurosawa and A. M. Nakamura and K. Ogawa and S. Sugita and T. Morota and R. Honda and S. Kameda and E. Tatsumi and Y. Cho and K. Yoshioka and Y. Yokota and M. Hayakawa and M. Matsuoka and N. Sakatani and M. Yamada and T. Kouyama and H. Suzuki and C. Honda and T. Yoshimitsu and T. Kubota and H. Demura and T. Yada and M. Nishimura and K. Yogata and A. Nakato and M. Yoshitake and A. I. Suzuki and S. Furuya and K. Hatakeda and A. Miyazaki and K. Kumagai and T. Okada and M. Abe and T. Usui and T. R. Ireland and M. Fujimoto and T. Yamada and M. Arakawa and H. C. Connolly Jr and A. Fujii and S. Hasegawa and N. Hirata and C. Hirose and S. Hosoda and Y. Ilijima and H. Ikeda and M. Ishiguro and Y. Ishihara and T. Iwata and S. Kikuchi and K. Kitazato and D. S. Lauretta and G. Libourel and B. Marty},

doi = {10.1126/science.abj8624},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Science},

abstract = {The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and sub-surface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu’s boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 2020 December 6. We describe the morphology of \>5 g of returned pebbles and sand. Their diverse color, shape and structure are consistent with the observed materials of Ryugu ; we conclude they are a representative sample of the asteroid},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Broadley_etal2022,

title = {Origin of life-forming volatile elements in the inner Solar System},

author = {M. W. Broadley and D. V. Bekaert and L. Piani and E. F\"{u}ri and B. Marty},

doi = {10.1038/s41586-022-05276-x},

year  = {2022},

date = {2022-01-01},

journal = {Nature},

volume = {611},

pages = {245--255},

abstract = {Volatile elements such as hydrogen, carbon, nitrogen and oxygen are essential ingredients to build habitable worlds like Earth, but their origin and evolution on terrestrial planets remain highly debated. Here we discuss the processes that distributed these elements throughout the early Solar System and how they then became incorporated into planetary building blocks. Volatiles on Earth and the other terrestrial planets appear to have been heterogeneously sourced from different Solar System reservoirs. The sources of planetary volatiles and the timing at which they were accreted to growing planets probably play a crucial role in controlling planet habitability.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Tait_etal2022,

title = {Preliminary planning for Mars Sample Return (MSR) curation activities in a Sample Receiving Facility (SRF)},

author = {K. T. Tait and F. M. McCubbin and C. L. Smith and C. B. Agee and and B. Marty},

doi = {10.1089/ast.2021.0105},

year  = {2022},

date = {2022-01-01},

journal = {Astrobiology},

volume = {22},

number = {S1},

abstract = {The Mars Sample Return Planning Group 2 (MSPG2) was tasked with identifying the steps that encompass all the curation activities that would happen within the MSR Sample Receiving Facility (SRF) and any anticipated curation-related requirements. An area of specific interest is the necessary analytical instrumentation. The SRF would be a Biosafety Level-4 facility where the returned MSR flight hardware would be opened, the sample tubes accessed, and the martian sample material extracted from the tubes. Characterization of the essential attributes of each sample would be required to provide enough information to prepare a sample catalog used in guiding the preparation of sample-related proposals by the world’s research community and informing decisions by the sample allocation committee. The sample catalog would be populated with data and information generated during all phases of activity, including data derived concurrent with Mars 2020 sample-collecting rover activity, sample transport to Earth, and initial sample characterization within the SRF. We conclude that initial sample characterization can best be planned as a set of three sequential phases, which we have called Pre-Basic Characterization (Pre-BC), Basic Characterization (BC), and Preliminary Examination (PE), each of which requires a certain amount of instrumentation. Data on specific samples and subsamples obtained during sample safety assessments and time-sensitive scientific investigations would also be added to the catalog. There are several areas where future work would be beneficial to prepare for the receipt of samples, which would include the design of a sample tube isolation chamber and a strategy for opening the sample tubes and removing dust from the tube exteriors.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Grewal_etal2021,

title = {A very early origin of isotopically distinct nitrogen in inner Solar System protoplanets},

author = {D. S. Grewal and R. Dasgupta and B. Marty},

doi = {10.1038/s41550-020-01283-y},

year  = {2021},

date = {2021-01-01},

journal = {Nature Astronomy},

abstract = {Understanding the origin of life-essential volatiles such as nitrogen (N) in the Solar System and beyond is critical to evaluate the potential habitability of rocky planets1--5. Whether the inner Solar System planets accreted these volatiles from their inception or had an exogenous delivery from the outer Solar System is, however, not well understood. Using previously published data of nucleosynthetic anomalies of nickel, molybdenum, tungsten and ruthenium in iron meteorites along with their 15N/14N ratios, here we show that the earliest formed protoplanetsin the inner and outer protoplanetary disk accreted isotopically distinct N. While the Sun and Jupiter captured N from nebular gas6, concomitantly growing protoplanets in the inner and outer disk possibly sourced their N from organicsand/or dust---with each reservoir having a different N isotopic composition. A distinct N isotopic signature of the inner Solar System protoplanets coupled with their rapid accretion7,8 suggests that non-nebular, isotopically processed Nwas ubiquitous in their growth zone between 0 and textasciitilde0.3 Myr after Solar System formation. Because the 15N/14N ratio of the bulk silicate Earth falls between that of the inner and outer Solar System reservoirs, we infer that N in the present-dayrocky planets represents a mixture of both inner and outer Solar System material.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Avice+Marty2020,

title = {Perspectives on atmospheric evolution from noble gas and nitrogen isotopes on Earth, Mars \& Venus},

author = {G. Avice and B. Marty},

doi = {10.1007/s11214-020-00655-0},

year  = {2020},

date = {2020-01-01},

journal = {Space Science Reviews},

volume = {126},

pages = {36},

abstract = {The composition of an atmosphere has integrated the geological history of the entire planetary body. However, the long-term evolutions of the atmospheres of the terrestrial planets are not well documented. For Earth, there were until recently only few direct records of atmospheretextquoterights composition in the distant past, and insights came mainly from geochemical or physical proxies and/or from atmospheric models pushed back in time. Here we review innovative approaches on new terrestrial samples that led to the determination of the elemental and isotopic compositions of key geochemical tracers, namely noble gases and nitrogen. Such approaches allowed one to investigate the atmospheretextquoterights evolution through geological period of time, and to set stringent constraints on the past atmospheric pressure and on the salinity of the Archean oceans. For Mars, we review the current state of knowledge obtained from analyses of Martian meteorites, and from the direct measurements of the composition of the present-day atmosphere by rovers and spacecrafts. Based on these measurements, we explore divergent models of the Martian and Terrestrial atmospheric evolutions. For Venus, only little is known, evidencing the critical need for dedicated missions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2020,

title = {Xenon isotopes in Archean and Proterozoic insoluble organic matter: A robust indicator of syngenecity?},

author = {D. V. Bekaert and M. W. Broadley and F. Delarue and Z. Druzhinina and G. Paris and F. Robert and K. Sugitani and B. Marty},

doi = {10.1016/j.precamres.2019.105505},

year  = {2020},

date = {2020-01-01},

journal = {Precambrian Research},

volume = {336},

pages = {105505},

abstract = {Insoluble organic materials (kerogens) isolated from ancient sedimentary rocks provide unique insights into the evolution of early life. However, establishing whether these kerogens are indeed syngenetic with the deposition of associated sedimentary host rocks, or contain contribution from episodes of secondary deposition, is not straightforward. Novel geochemical criterions are therefore required to test the syngenetic origin of Archean organic materials. On the one hand, the occurrence of mass-independent fractionation of sulphur isotopes (MIF-S) provides a tool to test the Archean origin of ancient sedimentary rocks. Determining the isotope composition of sulphur within kerogens whilst limiting the contribution from associated minerals (e.g., nano-pyrites) is however challenging. On the other hand, the Xe isotope composition of the Archean atmosphere has been shown to present enrichments in the light isotopes relative to its modern composition, together with a mono-isotopic deficit in 129Xe. Given that the isotopic composition of atmospheric Xe evolved through time by mass dependent fractionation (MDF) until textasciitilde2.5 to 2.0 Ga, the degree of MDF of Xe isotopes trapped in kerogens could provide a time stamp for the last chemical equilibration between organic matter and the atmosphere. However, the extent to which geological processes could affect the signature of Xe trapped in ancient kerogen remains unclear. In this contribution, we present new Ar, Kr and Xe isotopic data for four kerogens isolated from 3.4 to 1.8 Gy-old cherts and confirm that Xe isotopes from the Archean atmosphere can be retained within kerogens. However, new Xe-derived model ages are lower than expected from the ages of host rocks, indicating that initially trapped Xe components were at least partially lost and/or mixed together with some Xe carried out by younger generations of organic materials, therefore complicating the Xe-based dating method. Whilst non-null $Delta$33S values and 129Xe deficits relative to modern atmosphere constitute reliable imprints from the Archean atmosphere, using Xe isotopes to provide information on the syngenetic origin of ancient organic matter appears to be a promising -- but not unequivocal -- tool that calls for further analytical development.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2020_2,

title = {The origin and fate of volatile elements on Earth revisited in light of noble gas data obtained from comet 67P/Churyumov-Gerasimenko},

author = {D. V. Bekaert and M. W. Broadley and B. Marty},

doi = {10.1038/s41598-020-62650-3},

year  = {2020},

date = {2020-01-01},

journal = {Scientific Reports},

volume = {10},

pages = {5796},

abstract = {The origin of terrestrial volatiles remains one of the most puzzling questions in planetary sciences. The timing and composition of chondritic and cometary deliveries to Earth has remained enigmatic due to the paucity of reliable measurements of cometary material. This work uses recently measured volatile elemental ratios and noble gas isotope data from comet 67P/Churyumov-Gerasimenko (67P/C-G), in combination with chondritic data from the literature, to reconstruct the composition of Earthtextquoterights ancient atmosphere. Comets are found to have contributed textasciitilde20% of atmospheric heavy noble gases (i.e., Kr and Xe) but limited amounts of other volatile elements (water, halogens and likely organic materials) to Earth. These cometary noble gases were likely mixed with chondritic ?\u{I} and not solar ?\u{I} sources to form the atmosphere. We show that an ancient atmosphere composed of chondritic and cometary volatiles is more enriched in Xe relative to the modern atmosphere, requiring that 8--12 times the present-day inventory of Xe was lost to space. This potentially resolves the long-standing mystery of Earthtextquoterights textquotelefttextquoteleftmissing xenontextquoterighttextquoteright, with regards to both Xe elemental depletion and isotopic fractionation in the atmosphere. The inferred Kr/H2O and Xe/H2O of the initial atmosphere suggest that Earthtextquoterights surface volatiles might not have been fully delivered by the late accretion of volatile-rich carbonaceous chondrites. Instead, textquotelefttextquoteleftdrytextquoterighttextquoteright materials akin to enstatite chondrites potentially constituted a significant source of chondritic volatiles now residing on the Earthtextquoterights surface. We outline the working hypotheses, implications and limitations of this model in the last section of this contribution},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bermingham_etal2020,

title = {The NC-CC isotope dichotomy : Implications for the chemical and isotopic evolution of the early solar system.},

author = {K. R. Bermingham and E. F\"{u}ri and K. Lodders and B. Marty},

doi = {10.1007/s11214-020-00748-w},

year  = {2020},

date = {2020-01-01},

journal = {Space Science Reviews},

volume = {216},

number = {8},

pages = {1--29},

abstract = {Understanding the formation of our planetary system requires identification of the materials from which it originated and the accretion processes that produced the planets. The compositional evolution of the solar system can be constrained by synthesizing astronomical datasets and numerical models with elemental and isotopic compositions from objects that directly sampled the disk : meteorites and their constituents (chondrules, refractory inclusions, and matrix). This contribution reviews constraints on early solar system evolution provided by the so-called non-carbonaceous (NC) and carbonaceous chondrite (CC) groups and their relationship to the volatile element characteristics of chondritic meteorites. In previous work, the NC or CC character of a parent body was used to infer its accretion location in the protoplanetary disk. The NC groups purportedly originated in the inner disk, and the CC groups were derived from the outer disk, where the NC and CC regions of the disk may have been separated early on by proto-Jupiter, a pressure maximum, or a dust trap in the disk. The tenet that all CC parent bodies accreted in the outer disk is, in part, based on evidence that a handful of CC meteorites are enriched in volatile species compared to NC meteorites. Here, it is reviewed if and how the volatile element and nucleosynthetic isotope compositions of meteorites can be linked to accretion locations within the disk. The nucleosynthetic isotope compositions of whole rock meteorite samples contrast the trends found for their major volatile element compositions (i.e., C, N, and O). Although there may be an increase in volatile abundances when comparing some stony NC and CC meteorites and their inferred accretion locations within the disk, this is not necessarily a general rule. The difficulties with inferring parent body accretion locations are discussed. It is found that it cannot always be assumed that parent bodies which formed in the CC reservoir are textquotelefttextquoteleftvolatile-richtextquoterighttextquoteright relative to those that formed in the NC reservoir which are textquotelefttextquoteleftvolatile-poortextquoterighttextquoteright. Consequently, tracing the origin of terrestrial volatiles using the NC-CC isotope dichotomy remains challenging},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bouhifd_etal2020,

title = {Potential of Earthtextquoterights core as a reservoir for noble gases : Case for helium and neon},

author = {M. A. Bouhifd and A. P. Jephcoat and D. Porcelli and S. P. Kelley and B. Marty},

doi = {10.7185/geochemlet.2028},

year  = {2020},

date = {2020-01-01},

journal = {Geochemical Perspectives Letters},

volume = {15},

pages = {15--18},

abstract = {This study investigates metal--silicate partitioning of neon (DNe) under the likely conditions of early Earthtextquoterights core formation : up to 16 GPa, �`u 3000 K and an oxygen fugacity near IW-2 (2 log units below the Iron-Wüstite buffer). We find that the DNe coefficients range between 10−2 and 10−1. These partition coefficients are only one of the controlling factors of noble gas distributions within the early Earth : because, even if DHe and DNe are low (�`u10−4), there may have been sufficient noble gases present in the mantle to supply a significant quantity of He and Ne to the core. Assuming gasmelt equilibrium of the molten proto-Earth with a nebular gas composition and concomitant metal-silicate differentiation, the core would have inherited and maintained throughout Earthtextquoterights history high 3He/4He ratios and low 3He/22Ne ratios (\<0.6), making the core a potential source of primordial light noble gases in mantle plumes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Broadley_etal2020,

title = {Identification of chondritic krypton and xenon in Yellowstone gases and the timing of terrestrial volatile accretion},

author = {M. W. Broadley and P. H. Barry and D. Bekaert and D. J. Byrne and A. Caracausi and C. J. Ballentine and B. Marty},

doi = {10.1073/pnas.2003907117},

year  = {2020},

date = {2020-01-01},

journal = {PNAS},

volume = {117},

number = {25},

pages = {13997--14004},

abstract = {Identifying the origin of noble gases in Earthtextquoterights mantle can provide crucial constraints on the source and timing of volatile (C, N, H2O, noble gases, etc.) delivery to Earth. It remains unclear whether the early Earth was able to directly capture and retain volatiles throughout accretion or whether it accreted anhydrously and subsequently acquired volatiles through later additions of chondritic material. Here, we report high-precision noble gas isotopic data from volcanic gases emanating from, in and around, the Yellowstone caldera (Wyoming, United States). We show that the He and Ne isotopic and elemental signatures of the Yellowstone gas requires an input from an undegassed mantle plume. Coupled with the distinct ratio of 129Xe to primordial Xe isotopes in Yellowstone compared with mid-ocean ridge basalt (MORB) samples, this confirms that the deep plume and shallow MORB mantles have remained distinct from one another for the majority of Earthtextquoterights history. Krypton and xenon isotopes in the Yellowstone mantle plume are found to be chondritic in origin, similar to the MORB source mantle. This is in contrast with the origin of neon in the mantle, which exhibits an isotopic dichotomy between solar plume and chondritic MORB mantle sources. The co-occurrence of solar and chondritic noble gases in the deep mantle is thought to reflect the heterogeneous nature of Earthtextquoterights volatile accretion during the lifetime of the protosolar nebula. It notably implies that the Earth was able to retain its chondritic volatiles since its earliest stages of accretion, and not only through late additions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Broadley_etal2020_2,

title = {Noble gas variations in ureilites and their implications for ureilite parent body formation},

author = {M. W. Broadley and D. V. Bekaert and B. Marty and A. Yamaguchi and J. A. Barrat},

doi = {10.1016/j.gca.2019.11.032},

year  = {2020},

date = {2020-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {270},

pages = {325--337},

abstract = {Ureilites are equilibrated carbon-rich olivine-pyroxene rocks from the partially melted mantle of a large (\>500 km diameter) heterogeneous parent body. Recently the ureilite parent body was interpreted as an incomplete mixture of material from two carbon-rich chondritic reservoirs, one (Mg-rich) with reduced iron, low $Delta$17O and low $delta$13C, and the other with oxidised iron, high $Delta$17O and high $delta$13C. Here we analyse noble gases (Ar, Kr and Xe) in six equilibrated (unbrecciated) ureilites from Northwest Africa (NWA 2236, NWA 7686, NWA 8049, NWA 8172, NWA 11032 and NWA 11368). We observe weak positive and negative correlations of $Delta$17O and Mg# with the elemental ratios of Ar/Xe and Kr/Xe, respectively, as well as a weak positive correlation of Mg# with the heavy isotopes of Xe. These correlations broadly support the idea of the two-component mixing hypothesis. Our analyses further suggest that the Mg-rich endmember was rich in Xe from presolar grains (HL-Xe) while the Mg-poorer component may have contained solar-derived noble gases. The observed correlations are less straightforward to reconcile with a recent model for the origin of the ureilite parent body, involving oxidation of metal by H2O from accreted ice with textquoteleftheavytextquoteright oxygen isotopes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Burgess_etal2020,

title = {Archean to Paleoproterozoic seawater halogen ratios recorded by fluid inclusions in chert and hydrothermal quartz},

author = {R. Burgess and S. L. Goldsmith and H. Sumino and J. D. Gilmour and B. Marty and M. Pujol and K. O. Konhauser},

doi = {10.2138/am-2020-7238},

year  = {2020},

date = {2020-01-01},

journal = {American Mineralogist},

volume = {105},

pages = {1317--1325},

abstract = {Past changes in the halogen composition of seawater are anticipated based on the differing behavior of chlorine and bromine that are strongly partitioned into seawater, relative to iodine, which is extremely depleted in modern seawater and enriched in marine sediments due to biological uptake. Here we assess the use of chert, a chemical sediment that precipitated throughout the Precambrian, as a proxy for halide ratios in ancient seawater. We determine a set of criteria that can be used to assess the primary nature of halogens and show that ancient seawater Br/Cl and I/Cl ratios can be resolved in chert samples from the 2.5 Ga Dales Gorge Member of the Brockman Banded Iron Formation, Hamersley Group, Western Australia. The values determined of Br/Cl textasciitilde2 texttimes 10-3 M and I/Cl textasciitilde30 texttimes 10-6 M are comparable to fluid inclusions in hydrothermal quartz from the 3.5 Ga North Pole area, Pilbara Craton, Western Australia, that were the subject of previous reconstructions of ancient ocean salinity and atmospheric isotopic composition. While the similar Br/Cl and I/Cl values indicate no substantial change in the ocean halide system over the interval 2.5--3.5Ga, compared to modern seawater, the ancient ocean was enriched in Br and I relative to Cl. The I/Cl value is intermediate between bulk Earth (assumed chondritic) and the modern seawater ratio, which can be explained by a smaller organic reservoir because this is the major control on marine iodine at the present day. Br/Cl ratios are about 30% higher than both modern seawater and contemporary seafloor hydrothermal systems, perhaps indicating a stronger mantle buffering of seawater halogens during the Archean.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Charnay_etal2020,

title = {Is the faint young sun problem for Earth solved ?},

author = {B. Charnay and E. T. Wolf and B. Marty and F. Forget},

doi = {10.1007/s11214-020-00711-9},

year  = {2020},

date = {2020-01-01},

journal = {Space Science Reviews},

volume = {216},

pages = {90},

abstract = {Stellar evolution models predict that the solar luminosity was lower in the past, typically 20-25% lower during the Archean (3.8-2.5 Ga). Despite the fainter Sun, there is strong evidence for the presence of liquid water on Earthtextquoterights surface at that time. This textquotelefttextquoteleftfaint young Sun problemtextquoterighttextquoteright is a fundamental question in paleoclimatology, with important implications for the habitability of the early Earth, early Mars and exoplanets. Many solutions have been proposed based on the effects of greenhouse gases, atmospheric pressure, clouds, land distribution and Earthtextquoterights rotation rate. Here we review the faint young Sun problem for Earth, highlighting the latest geological and geochemical constraints on the early Earthtextquoterights atmosphere, and recent results from 3D global climate models and carbon cycle models. Based on these works, we argue that the faint young Sun problem for Earth has essentially been solved. Unfrozen Archean oceans were likely maintained by higher concentrations of CO2, consistent with the latest geological proxies, potentially helped by additional warming processes. This reinforces the expected key role of the carbon cycle for maintaining the habitability of terrestrial planets. Additional constraints on the Archean atmosphere and 3D fully coupled atmosphere-ocean models are required to validate this conclusion.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Labidi_etal2020,

title = {Hydrothermal 15N15N abundances constrain the origins of mantle nitrogen},

author = {J. Labidi and P. H. Barry and D. V. Bekaert and M. W. Broadley and B. Marty and T. Giunta and O. Warr and B. S. Sherwood and T. P. Fischer and G. Avice and A. Caracausi and C. J. Ballentine and S. A. Halldorsson and A. Stefansson and M. D. Kurz and I. E. Kohl and E. D. Young},

doi = {10.1038/s41586-020-2173-4},

year  = {2020},

date = {2020-01-01},

journal = {Nature},

volume = {580},

pages = {367--371},

abstract = {Nitrogen is the main constituent of the Earthtextquoterights atmosphere, but its provenance in the Earthtextquoterights mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earthtextquoterights accretion versus that subducted from the Earthtextquoterights surface is unclear1,2,3,4,5,6. Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare 15N15N isotopologue of N2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle $delta$15N (the fractional difference in 15N/14N from air), N2/36Ar and N2/3He. Our results show that negative $delta$15N values observed in gases, previously regarded as indicating a mantle origin for nitrogen7,8,9,10, in fact represent dominantly air-derived N2 that experienced 15N/14N fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the 15N15N data allow extrapolations that characterize mantle endmember $delta$15N, N2/36Ar and N2/3He values. We show that the Eifel region has slightly increased $delta$15N and N2/36Ar values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts11, consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has $delta$15N values substantially greater than that of the convective mantle, resembling surface components12,13,14,15, its N2/36Ar and N2/3He ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume $delta$15N values may both be dominantly primordial features.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Lammer_etal2020,

title = {Loss and fractionation of noble gas isotopes and moderately volatile elements from planetary embryos and early Venus, Earth and Mars},

author = {H. Lammer and M. Scherf and H. Kurokawa and Y. Ueno and C. Burger and T. Maindl and C. P. Johnstone and M. Leizinger and M. Benedikt and L. Fossati and K. G. Kislyakova and B. Marty and G. Avice and B. Fegley and P. Odert},

doi = {10.1007/s11214-020-00701-x},

year  = {2020},

date = {2020-01-01},

journal = {Space Science Reviews},

volume = {219},

number = {74},

abstract = {Here we discuss the current state of knowledge on how atmospheric escape processes can fractionate noble gas isotopes and moderately volatile rock-forming elements that populate primordial atmospheres, magma ocean related environments, and catastrophically outgassed steam atmospheres. Variations of isotopes and volatile elements in different planetary reservoirs keep information about atmospheric escape, composition and even the source of accreting material. We summarize our knowledge on atmospheric isotope ratios and discuss the latest evidence that proto-Venus and Earth captured small H2-dominated primordial atmospheres that were lost by hydrodynamic escape during and after the disk dispersed. All relevant thermal and non-thermal atmospheric escape processes that can fractionate various isotopes and volatile elements are discussed. Erosion of early atmospheres, crust and mantle by large planetary impactors are also addressed. Further, we discuss how moderately volatile elements such as the radioactive heat producing element 40K and other rock-forming elements such as Na can also be outgassed and lost from magma oceans that originate on large planetary embryos and accreting planets. Outgassed elements escape from planetary embryos with masses that are ≤𝑀Moon directly, or due to hydrodynamic drag of escaping H atoms originating from primordial- or steam atmospheres at more massive embryos. We discuss how these processes affect the final elemental composition and ratios such as K/U, Fe/Mg of early planets and their building blocks. Finally, we review modeling efforts that constrain the early evolution of Venus, Earth and Mars by reproducing their measured present day atmospheric 36Ar/38Ar, 20Ne/22Ne, noble gas isotope ratios and the role of isotopes on the loss of water and its connection to the redox state on early Mars.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mandt_etal2020,

title = {Tracing the origins of the ice giants through noble gas isotopic composition},

author = {K. E. Mandt and O. Mousis and J. Lunine and B. Marty and T. Smith and A. Luspay-Kuti and A. Aguichine},

doi = {10.1007/s11214-020-00723-5},

year  = {2020},

date = {2020-01-01},

journal = {Space Science Reviews},

volume = {216},

number = {99},

abstract = {The current composition of giant planet atmospheres provides information on how such planets formed, and on the origin of the solid building blocks that contributed to their formation. Noble gas abundances and their isotope ratios are among the most valuable pieces of evidence for tracing the origin of the materials from which the giant planets formed. In this review we first outline the current state of knowledge for heavy element abundances in the giant planets and explain what is currently understood about the reservoirs of icy building blocks that could have contributed to the formation of the Ice Giants. We then outline how noble gas isotope ratios have provided details on the original sources of noble gases in various materials throughout the solar system. We follow this with a discussion on how noble gases are trapped in ice and rock that later became the building blocks for the giant planets and how the heavy element abundances could have been locally enriched in the protosolar nebula. We then provide a review of the current state of knowledge of noble gas abundances and isotope ratios in various solar system reservoirs, and discuss measurements needed to understand the origin of the ice giants. Finally, we outline how formation and interior evolution will influence the noble gas abundances and isotope ratios observed in the ice giants today. Measurements that a future atmospheric probe will need to make include (1) the 3He/4He isotope ratio to help constrain the protosolar D/H and 3He/4He ; (2) the 20Ne/22Ne and 21Ne/22Ne to separate primordial noble gas reservoirs similar to the approach used in studying meteorites ; (3) the Kr/Ar and Xe/Ar to determine if the building blocks were Jupiter-like or similar to 67P/C-G and Chondrites ; (4) the krypton isotope ratios for the first giant planet observations of these isotopes ; and (5) the xenon isotopes for comparison with the wide range of values represented by solar system reservoirs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2020,

title = {An evaluation of the C/N ratio of the mantle from natural CO2-rich gas analysis : Geochemical and cosmochemical implications},

author = {B. Marty and M. Almayrac and P. H. Barry and D. Bekaert and M. W. Broadley and D. J. Byrne and C. J. Ballentine and A. Caracausi},

doi = {10.1016/j.epsl.2020.116574},

year  = {2020},

date = {2020-01-01},

journal = {Earth and Planetary Science Letters},

volume = {551},

pages = {116574},

abstract = {The terrestrial carbon to nitrogen ratio is a key geochemical parameter that can provide information on the nature of Earthtextquoterights precursors, accretion/differentiation processes of our planet, as well as on the volatile budget of Earth. In principle, this ratio can be determined from the analysis of volatile elements trapped in mantle-derived rocks like mid-ocean ridge basalts (MORB), corrected for fractional degassing during eruption. However, this correction is critical and previous attempts have adopted different approaches which led to contrasting C/N estimates for the bulk silicate Earth (BSE) (Marty and Zimmermann, 1999 ; Bergin et al., 2015). Here we consider the analysis of CO2-rich gases worldwide for which a mantle origin has been determined using noble gas isotopes in order to evaluate the C/N ratio of the mantle source regions. These gases experienced little fractionation due to degassing, as indicated by radiogenic ⁎ values (where 4He and 40Ar* are produced by the decay of U+Th, and 40K isotopes, respectively) close to the mantle production/accumulation values. The C/N and ratios of gases investigated here are within the range of values previously observed in oceanic basalts. They point to an elevated mantle C/N ratio (�`u350-470, molar) higher than those of potential cosmochemical accretionary endmembers. For example, the BSE C/N and ratios (160-220 and , respectively) are higher than those of CM-CI chondrites but within the range of CV-CO groups. This similarity suggests that the Earth accreted from evolved planetary precursors depleted in volatile and moderately volatile elements. Hence the high composition of the BSE may be an inherited feature rather than the result of terrestrial differentiation. The and ratios of the surface (atmosphere plus crust) and of the mantle cannot be easily linked to any known chondritic composition. However, these compositions are consistent with early sequestration of carbon into the mantle (but not N and noble gases), permitting the establishment of clement temperatures at the surface of our planet.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Piani_etal2020,

title = {Earthtextquoterights water may have been inherited from material similar to enstatite chondrite meteorites},

author = {L. Piani and Y. Marrocchi and T. Rigaudier and L. G. Vacher and D. Thomassin and B. Marty},

doi = {10.1126/science.aba1948},

year  = {2020},

date = {2020-01-01},

journal = {Science},

volume = {369},

number = {6507},

pages = {1110--1113},

abstract = {The origin of Earthtextquoterights water remains unknown. Enstatite chondrite (EC) meteorites have similar isotopic composition to terrestrial rocks and thus may be representative of the material that formed Earth. ECs are presumed to be devoid of water because they formed in the inner Solar System. Earthtextquoterights water is therefore generally attributed to the late addition of a small fraction of hydrated materials, such as carbonaceous chondrite meteorites, which originated in the outer Solar System where water was more abundant. We show that EC meteorites contain sufficient hydrogen to have delivered to Earth at least three times the mass of water in its oceans. EC hydrogen and nitrogen isotopic compositions match those of Earthtextquoterights mantle, so EC-like asteroids might have contributed these volatile elements to Earthtextquoterights crust and mantle.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Barnouin_etal2019,

title = {Shape of (101955) Bennu indicative of a rubble pile with internal stiffness},

author = {O. S. Barnouin and M. G. Daly and \& and The OSIRIS-REx Team. and B. Marty},

doi = {10.1038/s41561-019-0330-x},

year  = {2019},

date = {2019-01-01},

journal = {Nature Geoscience},

volume = {12},

pages = {247--252},

abstract = {The shapes of asteroids reflect interplay between their interior properties and the processes responsible for their formation and evolution as they journey through the Solar System. Prior to the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security--Regolith Explorer) mission, Earth-based radar imaging gave an overview of (101955) Bennutextquoterights shape. Here we construct a high-resolution shape model from OSIRIS-REx images. We find that Bennutextquoterights top-like shape, considerable macroporosity and prominent surface boulders suggest that it is a rubble pile. High-standing, north--south ridges that extend from pole to pole, many long grooves and surface mass wasting indicate some low levels of internal friction and/or cohesion. Our shape model indicates that, similar to other top-shaped asteroids, Bennu formed by reaccumulation and underwent past periods of fast spin, which led to its current shape. Today, Bennu might follow a different evolutionary pathway, with an interior stiffness that permits surface cracking and mass wasting.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2019,

title = {Novel insights into the degassing history of Earthtextquoterights mantle from high precision noble gas analysis of magmatic gas},

author = {D. Bekaert and M. W. Broadley and A. Caracausi and B. Marty},

doi = {10.1016/j.epsl.2019.115766.},

year  = {2019},

date = {2019-01-01},

journal = {Earth and Planetary Science Letters},

volume = {525},

number = {115766},

abstract = {The noble gas isotope composition of the mantle can provide unique insights into the origin and evolution of volatile elements on Earth. Xenon isotopes combine primordial signatures with contributions from extinct and extant radionuclides, therefore offering the potential to set constraints on both the nature of Earthtextquoterights planetary precursor(s) and the timing of their contributions. However, measuring the Xe isotope composition of mantle-derived samples to sufficiently high-precision has proven difficult due to (i) large occurrence of a modern-like atmospheric component in the mantle, and (ii) contribution from shallow and post-eruptive atmospheric contamination. Mantle-derived samples therefore exhibit only small deviations from the modern atmospheric composition, making the identification and deconvolution of mantle-derived Xe signals challenging. Here, we use the Giggenbach sampling method to concentrate magmatic noble gases from the Eifel volcanic area (Germany) into glass bottles in order to conduct high-precision analyses of Ne, Ar and Xe isotopes. The three samples collected from Victoriaquelle and Schwefelquelle wells (South East Eifel) show variable contributions from atmospheric contamination, with the least contaminated sample reaching 40Ar/36Ar �`u8,300. Our data indicate that the mantle beneath the Eifel volcanic area, and by extension the Central European Volcanic Province, resembles the convective upper mantle reservoir with limited evidence for an OIB-like deep plume source contribution. It has a geochemical signature that is similar (e.g. in Ne isotopic composition, 40Ar/36Ar, 129Xe/130Xe and 129Xe/136Xe) to the mantle source of the so-called popping rocks (thought to best represent the upper mantle), with an additional source of 238U-derived Xe and low 3He/4He that we attribute to the influence of an ancient subducted component (HIMU). A dichotomy exists between the main sources of fissiogenic xenon isotopes measured in popping rocks and Eifel gas, which appear to be mainly derived from 244Pu and 238U, respectively. According to their respective ratios of 244Pu- to 238U-derived Xe, the mantle sources for Eifel volcanism and popping rocks would have experienced extensive and limited degassing, respectively. In this regard, high Pu--Xe/(Pu+U)--Xe may no longer be considered as being indicative of a mantle deep origin, therefore calling for the geochemical differences between plume and MORB sources to be redefined, with the possibility that volatile signatures within the solid Earth may be more heterogeneously distributed than previously thought.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2019_2,

title = {Coulomb explosion of multiply ionized xenon in water ice},

author = {D. Bekaert and M. S. Gudipati and B. Henderson and B. Marty},

doi = {doi:10.2343/geochemj.2.0548},

year  = {2019},

date = {2019-01-01},

journal = {Geochemical Journal},

volume = {53},

number = {81},

pages = {69},

abstract = {Laboratory investigations of noble gas trapping in amorphous water ice have been used to predict the noble gas composition of comets and infer on the origin of volatile elements within planetary bodies. However, the recent measurementof the noble gas composition of ice sublimating from comet 67P/Churyumov-Gerasimenko by the Rosetta mission calls for novel experiments regarding the mechanisms of noble gas trapping and evolution in cometary ice analogues. Here, weinvestigated the ionization dynamics of Xe atoms interacting with water ice using the recently developed Resonant Two-Step Laser Ablation Mass Spectrometry (2S-LAI-MS). Xenon-water mixed ice was ablated with an infrared beam set on the maximum absorption wavelength for water (l = 2948 nm) at which xenon atoms are kept neutral. Subsequent multiple ionization of xenon and oxygen resulted in periodic Coulomb explosions of Xen+ components (n OE [1;6]) and ionized water degradation products (OH+, H+, O+, O2+, O3+). Such explosions could only be detected when Xe and water were mixed together in ice, and not when separated in two overlaid layers. This paper discusses the potential mechanisms accounting for the generation of Coulomb explosions in these experiments and its relevance to cometary ice at closer distances to perihelion. We conclude that multiple ionization of xenon and oxygen in our experiment may be due to electron impact processes resembling cometary electron and ion bombardment, whereby energetic particles of hundreds of eV to a few keV are accelerated towards the comettextquoterights nucleus. Electron and ion bombardment could induce significant chemical modifications to, and potentially outgassing from, the cometary surface.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hamilton_etal2019,

title = {Evidence for widespread hydrated minerals on asteroid (101955) Bennu},

author = {V. E. Hamilton and A. A. Simon and \& and The OSIRIS-REx team. and B. Marty},

doi = {1038/s41550-019-0722-2},

year  = {2019},

date = {2019-01-01},

journal = {Nature Astronomy},

volume = {3},

pages = {332--340},

abstract = {Early spectral data from the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission reveal evidence for abundant hydrated minerals on the surface of near-Earth asteroid (101955) Bennu in the form of a near-infrared absorption near 2.7thinspacetextmum and thermal infrared spectral features that are most similar to those of aqueously altered CM-type carbonaceous chondrites. We observe these spectral features across the surface of Bennu, and there is no evidence of substantial rotational variability at the spatial scales of tens to hundreds of metres observed to date. In the visible and near-infrared (0.4 to 2.4thinspacetextmum) Bennutextquoterights spectrum appears featureless and with a blue (negative) slope, confirming previous ground-based observations. Bennu may represent a class of objects that could have brought volatiles and organic chemistry to Earth.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hergenrother_etal2019,

title = {The operational environment and rotational acceleration of asteroid (101955) Bennu from OSIRIS-REx observations},

author = {C. W. Hergenrother and C. K. Maleszewski and M. C. Nolan and \& and The OSIRIS-REx Team. and B. Marty},

doi = {10.1038/s41467-019-09213-x},

year  = {2019},

date = {2019-01-01},

journal = {Nature Communications},

volume = {10},

number = {1291},

abstract = {During its approach to asteroid (101955) Bennu, NASAtextquoterights Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft surveyed Bennutextquoterights immediate environment, photometric properties, and rotation state. Discovery of a dusty environment, a natural satellite, or unexpected asteroid characteristics would have had consequences for the missiontextquoterights safety and observation strategy. Here we show that spacecraft observations during this period were highly sensitive to satellites (sub-meter scale) but reveal none, although later navigational images indicate that further investigation is needed. We constrain average dust production in September 2018 from Bennutextquoterights surface to an upper limit of 150thinspacegthinspaces--1 averaged over 34thinspacemin. Bennutextquoterights disk-integrated photometric phase function validates measurements from the pre-encounter astronomical campaign. We demonstrate that Bennutextquoterights rotation rate is accelerating continuously at 3.63thinspacetextpmthinspace0.52thinspacetexttimesthinspace10--6thinspacedegrees day--2, likely due to the Yarkovsky--OtextquoterightKeefe--Radzievskii--Paddack (YORP) effect, with evolutionary implications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Lauretta_etal2019,

title = {The unexpected surface of asteroid (101955) Bennu},

author = {D. S. Lauretta and D. N. DellaGiustina and C. A. Bennett and \& and The OSIRIS-REx Team. and B. Marty},

doi = {10.1038/s41586-019-1033-6},

year  = {2019},

date = {2019-01-01},

journal = {Nature},

volume = {568},

pages = {55--60},

abstract = {NASAtextquoterightS Origins, Spectral Interpretation, Resource Identification and Security-Regolith Explorer (OSIRIS-REx) spacecraft recently arrived at the near-Earth asteroid (101955) Bennu, a primitive body that represents the objects that may have brought prebiotic molecules and volatiles such as water to Earth1. Bennu is a low-albedo B-type asteroid2 that has been linked to organic-rich hydrated carbonaceous chondrites3. Such meteorites are altered by ejection from their parent body and contaminated by atmospheric entry and terrestrial microbes. Therefore, the primary mission objective is to return a sample of Bennu to Earth that is pristine---that is, not affected by these processes4. The OSIRIS-REx spacecraft carries a sophisticated suite of instruments to characterize Bennutextquoterights global properties, support the selection of a sampling site and document that site at a sub-centimetre scale5,6,7,8,9,10,11. Here we consider early OSIRIS-REx observations of Bennu to understand how the asteroidtextquoterights properties compare to pre-encounter expectations and to assess the prospects for sample return. The bulk composition of Bennu appears to be hydrated and volatile-rich, as expected. However, in contrast to pre-encounter modelling of Bennutextquoterights thermal inertia12 and radar polarization ratios13---which indicated a generally smooth surface covered by centimetre-scale particles---resolved imaging reveals an unexpected surficial diversity. The albedo, texture, particle size and roughness are beyond the spacecraft design specifications. On the basis of our pre-encounter knowledge, we developed a sampling strategy to target 50-metre-diameter patches of loose regolith with grain sizes smaller than two centimetres4. We observe only a small number of apparently hazard-free regions, of the order of 5 to 20 metres in extent, the sampling of which poses a substantial challenge to mission success},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2019,

title = {Geochemical evidence for high volatile fluxes from the mantle at the end of the Archaean},

author = {B. Marty and D. V. Bekaert and M. W. Broadley},

doi = {10.1038/s41586-019-1745-7},

year  = {2019},

date = {2019-01-01},

journal = {Nature},

volume = {575},

number = {4865},

pages = {485--488},

abstract = {The exchange of volatile species---water, carbon dioxide, nitrogen and halogens---between the mantle and the surface of the Earth has been a key driver of environmental changes throughout Earthtextquoterights history. Degassing of the mantle requires partial melting and is therefore linked to mantle convection, whose regime and vigour in the Earthtextquoterights distant past remain poorly constrained1,2. Here we present direct geochemical constraints on the flux of volatiles from the mantle. Atmospheric xenon has a monoisotopic excess of 129Xe, produced by the decay of extinct 129I. This excess was mainly acquired during Earthtextquoterights formation and early evolution3, but mantle degassing has also contributed 129Xe to the atmosphere through geological time. Atmospheric xenon trapped in samples from the Archaean eon shows a slight depletion of 129Xe relative to the modern composition4,5, which tends to disappear in more recent samples5,6. To reconcile this deficit in the Archaean atmosphere by mantle degassing would require the degassing rate of Earth at the end of the Archaean to be at least one order of magnitude higher than today. We demonstrate that such an intense activity could not have occurred within a plate tectonics regime. The most likely scenario is a relatively short (about 300 million years) burst of mantle activity at the end of the Archaean (around 2.5 billion years ago). This lends credence to models advocating a magmatic origin for drastic environmental changes during the Neoarchaean era, such as the Great Oxidation Event.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Scheeres_etal2019,

title = {The dynamic geophysical environment of (101955) Bennu based on OSIRIS-REx measurements},

author = {D. J. Scheeres and J. W. McMahon and A. S. French and The OSIRIS-REx Team. and B. Marty},

year  = {2019},

date = {2019-01-01},

journal = {Nature Astronomy},

abstract = {The top-shaped morphology characteristic of asteroid (101955) Bennu, often found among fast-spinning asteroids and binary asteroid primaries, may have contributed substantially to binary asteroid formation. Yet a detailed geophysical analysis of this morphology for a fast-spinning asteroid has not been possible prior to the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission. Combining the measured Bennu mass and shape obtained during the Preliminary Survey phase of the OSIRIS-REx mission, we find a notable transition in Bennutextquoterights surface slopes within its rotational Roche lobe, defined as the region where material is energetically trapped to the surface. As the intersection of the rotational Roche lobe with Bennutextquoterights surface has been most recently migrating towards its equator (given Bennutextquoterights increasing spin rate), we infer that Bennutextquoterights surface slopes have been changing across its surface within the last million years. We also find evidence for substantial density heterogeneity within this body, suggesting that its interior is a mixture of voids and boulders. The presence of such heterogeneity and Bennutextquoterights top shape are consistent with spin-induced failure at some point in its past, although the manner of its failure cannot yet be determined. Future measurements by the OSIRIS-REx spacecraft will provide insight into and may resolve questions regarding the formation and evolution of Bennutextquoterights top-shape morphology and its link to the formation of binary asteroids.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Tuller-Ross_etal2019,

title = {Potassium isotope systematics of oceanic basalts},

author = {B. Tuller-Ross and B. Marty and H. Chen and K. A. Kelley and H. Lee and K. Wang},

doi = {10.1016/j.gca.2019.06.001},

year  = {2019},

date = {2019-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {259},

pages = {144--154},

abstract = {High-temperature isotope fractionation during partial melting and other igneous differentiation processes has been observed in many non-traditional isotope systems. The potassium (K) isotope system has not been extensively investigated historically due to the lack of high-precision analysis methods ; however, the recent development of the Multi-Collector Inductively Coupled Plasma Mass Spectrometer (MC-ICP-MS) now allows for high-precision potassium isotope analysis. In this study, we utilized this new method to analyze 51 geologically, geographically, and geochemically diverse oceanic basalt samples including 32 mid-ocean ridge basalts (MORB), 3 back-arc basin basalts (BABB), and 16 oceanic island basalts (OIB). We observed a limited variation of 41K/39K ratios across our spread of samples. This variation in mantle-derived rocks is restricted compared to the large K isotopic fractionation observed in low-temperature systems. The averages of MORBs, BABBs, and OIBs are −0.44 textpm 0.17texttenthousand (2sd), −0.44 textpm 0.08texttenthousand, and −0.41 textpm 0.16texttenthousand, respectively, and there is no geographical variation (e.g., Indian vs. Pacific MORBs) in terms of K isotopes. Among all samples, there are two outliers, in which we have observed evidence of secondary mineral formation (i.e., palagonite) due to interaction with seawater. These two outliers have a K isotopic composition significantly heavier than other unaltered samples, close to the K isotopic composition of seawater. The grand average of all pristine samples is −0.43 textpm 0.17texttenthousand (2sd) which agrees well with the Bulk Silicate Earth (BSE) value previously defined. This new study indicates the homogeneity of K isotopes in the mantle and suggests that, since K will not resolvably fractionate during partial melting, any observable fractionation of K isotopes in primitive basalts is likely due to low-temperature, post-eruptive alteration processes. This conclusion is critical for understanding the initial bulk composition of the Earth and it is essential for any interplanetary comparison.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DellaGiustina_etal2019,

title = {Properties of rubble-pile asteroid (101955) Bennu from OSIRIS-REx imaging and thermal analysis},

author = {D. N. DellaGiustina and J. P. Emery and \& and OSIRIS-REx Team. and B. Marty},

doi = {10.1038/s41550-019-0731-1},

year  = {2019},

date = {2019-01-01},

urldate = {2019-01-01},

journal = {Nature Astronomy},

volume = {3},

pages = {341--351},

abstract = {Establishing the abundance and physical properties of regolith and boulders on asteroids is crucial for understanding the formation and degradation mechanisms at work on their surfaces. Using images and thermal data from NASAtextquoterights Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft, we show that asteroid (101955) Bennutextquoterights surface is globally rough, dense with boulders, and low in albedo. The number of boulders is surprising given Bennutextquoterights moderate thermal inertia, suggesting that simple models linking thermal inertia to particle size do not adequately capture the complexity relating these properties. At the same time, we find evidence for a wide range of particle sizes with distinct albedo characteristics. Our findings imply that ages of Bennutextquoterights surface particles span from the disruption of the asteroidtextquoterights parent body (boulders) to recent in situ production (micrometre-scale particles).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Walsch_etal2019,

title = {Craters, boulders and regolith of (101955) Bennu indicative of an old and dynamic surface},

author = {K. J. Walsch and E. R. Jawin and \& and The OSIRIS-REx Team. and B. Marty},

doi = {10.1038/s41561-019-0326-6},

year  = {2019},

date = {2019-01-01},

urldate = {2019-01-01},

journal = {Nature Geoscience},

volume = {12},

pages = {242--246},

abstract = {Small, kilometre-sized near-Earth asteroids are expected to have young and frequently refreshed surfaces for two reasons : collisional disruptions are frequent in the main asteroid belt where they originate, and thermal or tidal processes act on them once they become near-Earth asteroids. Here we present early measurements of numerous large candidate impact craters on near-Earth asteroid (101955) Bennu by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) mission, which indicate a surface that is between 100 million and 1 billion years old, predating Bennutextquoterights expected duration as a near-Earth asteroid. We also observe many fractured boulders, the morphology of which suggests an influence of impact or thermal processes over a considerable amount of time since the boulders were exposed at the surface. However, the surface also shows signs of more recent mass movement : clusters of boulders at topographic lows, a deficiency of small craters and infill of large craters. The oldest features likely record events from Bennutextquoterights time in the main asteroid belt.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Avice_etal2018,

title = {Noble gases and nitrogen in Tissint reveal the composition of the Mars atmosphere},

author = {G. Avice and D. V. Bekaert and H. Chennaoui Aoudjehane and B. Marty},

doi = {10.7185/geochemlet.1802},

year  = {2018},

date = {2018-01-01},

journal = {Geochemical Perspectives Letters},

volume = {6},

pages = {11--16},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Avice_etal2018_2,

title = {Evolution of atmospheric xenon and other noble gases inferred from Archean to Paleoproterozoic rocks},

author = {G. Avice and B. Marty and R. Burgess and A. Hofmann and P. Philippot and K. Zahnle and D. Zakharov},

doi = {10.1016/j.gca.2018.04.018},

year  = {2018},

date = {2018-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {232},

pages = {82--100},

abstract = {We have analyzed ancient atmospheric gases trapped in fluid inclusions contained in minerals of Archean (3.3 Ga) to Paleozoic (404 Ma) rocks in an attempt to document the evolution of the elemental composition and isotopic signature of the atmosphere with time. Doing so, we aimed at understanding how physical and chemical processes acted over geological time to shape the modern atmosphere. Modern atmospheric xenon is enriched in heavy isotopes by 30--40texttenthousand u-1 relative to Solar or Chondritic xenon. Previous studies demonstrated that, 3.3 Ga ago, atmospheric xenon was isotopically fractionated (enriched in the light isotopes) relative to the modern atmosphere, by 12.9 textpm 1.2 (1r) texttenthousand u-1, whereas krypton was isotopically identical to modern atmospheric Kr. Details about the specific and progressive isotopic fractionation of Xe during the Archean, originally proposed by Pujol et al. (2011), are now well established by this work. Xe isotope fractionation has evolved from 21texttenthousand u-1 at 3.5 Ga to 12.9texttenthousand u-1 at 3.3 Ga. The current dataset provides some evidence for stabilization of the Xe fractionation between 3.3 and 2.7 Ga. However, further studies will be needed to confirm this observation. After 2.7 Ga, the composition kept evolving and reach the modern-like atmospheric Xe composition at around 2.1 Ga ago. Xenon may be the second atmospheric element, after sulfur, to show a secular isotope evolution during the Archean that ended shortly after the Archean-Proterozoic transition. Fractionation of xenon indicates that xenon escaped from Earth, probably as an ion, and that Xe escape stopped when the atmosphere became oxygen-rich. We speculate that the Xe escape was enabled by a vigorous hydrogen escape on the early anoxic Earth. Organic hazes, scavenging isotopically heavy Xe, could also have played a role in the evolution of atmospheric Xe. For 3.3 Ga-old samples, Ar-N2 correlations are consistent with a partial pressure of nitrogen (pN2) in the Archean atmosphere similar to, or lower than, the modern one, thus requiring other processes than a high pN2 to keep the Earthtextquoterights surface warm despite a fainter Sun. The nitrogen isotope composition of the atmosphere at 3.3 Ga was already modern-like, attesting to inefficient nitrogen escape to space since that time},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2018,

title = {Primordial heavy noble gases in the pristine Paris carbonaceous chondrite},

author = {D. Bekaert and Y. Marrocchi and A. Meshik and L. Remusat and B. Marty},

doi = {10.1111/maps.13213},

year  = {2018},

date = {2018-01-01},

journal = {Meteoritics \& Planetary Science},

volume = {54},

number = {2},

pages = {395--414},

abstract = {The Paris carbonaceous chondrite represents the most pristine carbonaceous chondrite, providing a unique opportunity to investigate the composition of early solar system materials prior to the onset of significant aqueous alteration. A dual origin (namely from the inner and outer solar system) has been demonstrated for water in the Paris meteorite parent body (Piani et al. 2018). Here, we aim to evaluate the contribution of outer solar system (cometary‐like) water ice to the inner solar system water ice using Xe isotopes. We report Ar, Kr, and high‐precision Xe isotopic measurements within bulk CM 2.9 and CM 2.7 fragments, as well as Ne, Ar, Kr, and Xe isotope compositions of the insoluble organic matter (IOM). Noble gas signatures are similar to chondritic phase Q with no evidence for a cometary‐like Xe component. Small excesses in the heavy Xe isotopes relative to phase Q within bulk samples are attributed to contributions from presolar materials. CM 2.7 fragments have lower Ar/Xe relative to more pristine CM 2.9 fragments, with no systematic difference in Xe contents. We conclude that Kr and Xe were little affected by aqueous alteration, in agreement with (1) minor degrees of alteration and (2) no significant differences in the chemical signature of organic matter in CM 2.7 and CM 2.9 areas (Vinogradoff et al. 2017). Xenon contents in the IOM are larger than previously published data of Xe in chondritic IOM, in line with the Xe component in Paris being pristine and preserved from Xe loss during aqueous alteration/thermal metamorphism},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2018_2,

title = {Origin and significance of cosmogenic signatures in vesicles of lunar basalt 15016},

author = {D. V. Bekaert and G. Avice and B. Marty},

doi = {10.1111/maps.13069},

year  = {2018},

date = {2018-01-01},

journal = {Meteoritics \& Planetary Science},

pages = {1--14},

abstract = {Abstract--Lunar basalt 15016 ( 3.3 Ga) is among the most vesicular (50% by volume) basalts recovered by the Apollo missions. We investigated the possible occurrence of indigenous lunar nitrogen and noble gases trapped in vesicles within basalt 15016, by crushing several cm-sized chips. Matrix/mineral gases were also extracted from crush residues by fusion with a CO2 laser. No magmatic/primordial component could be identified ; all isotope compositions, including those of vesicles, pointed to a cosmogenic origin. We found that vesicles contained 0.2%, 0.02%, 0.002%, and 0.02% of the total amount of cosmogenic 21Ne, 38Ar, 83Kr, and 126Xe, respectively, produced over the basalttextquoterights 300 Myr of exposure. Diffusion/recoil of cosmogenic isotopes from the basaltic matrix/ minerals to intergrain joints and vesicles is discussed. The enhanced proportion of cosmogenic Xe isotopes relative to Kr detected in vesicles could be the result of kinetic fractionation, through which preferential retention of Xe isotopes over Kr within vesicles might have occurred during diffusion from the vesicle volume to the outer space through microleaks. This study suggests that cosmogenic loss, known to be significant for 3He and 21Ne, and to a lesser extent for 36Ar (Signer et al. 1977), also occurs to a negligible extent for the heaviest noble gases Kr and Xe.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2018_3,

title = {Archean kerogen as a new tracer of atmospheric evolution: Implications for dating the widespread nature of early life},

author = {D. V. Bekaert and M. W. Broadley and F. Delarue and G. Avice and F. Robert and B. Marty},

doi = {10.1126/sciadv.aar2091},

year  = {2018},

date = {2018-01-01},

journal = {Science Advances},

volume = {4},

number = {2},

pages = {1--8},

abstract = {Understanding the composition of the Archean atmosphere is vital for unraveling the origin of volatiles and the environmental conditions that led to the development of life. The isotopic composition of xenon in the Archean atmosphere has evolved through time by mass-dependent fractionation from a precursor comprising cometary and solar/chondritic contributions (referred to as U-Xe). Evaluating the composition of the Archean atmosphere is challenging because limited amounts of atmospheric gas are trapped within minerals during their formation. We show that organic matter, known to be efficient at preserving large quantities of noble gases, can be used as a new archive of atmospheric noble gases. Xe isotopes in a kerogen isolated from the 3.0--billion-year--old Farrel Quartzite (Pilbara Craton, Western Australia) are mass fractionated by 9.8 textpm 2.1 per mil (texttenthousand) (2$sigma$) per atomic mass unit, in line with a progressive evolution toward modern atmospheric values. Archean atmospheric Xe signatures in kerogens open a new avenue for following the evolution of atmospheric composition through time. The degree of mass fractionation of Xe isotopes relative to the modern atmosphere can provide a time stamp for dating Archean kerogens and therefore narrowing the time window for the diversification of early life during the Archean eon.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2018_4,

title = {High-temperature ionization-induced synthesis of biologically relevant molecules in the protosolar nebula},

author = {D. V. Bekaert and S. Derenne and L. Tissandier and Y. Marrocchi and S. Charnoz and C. Anquetil and B. Marty},

doi = {10.3847/1538-4357/aabe7a},

year  = {2018},

date = {2018-01-01},

journal = {Astrophysical Journal},

volume = {859},

number = {142},

abstract = {Biologically relevant molecules (hereafter biomolecules) have been commonly observed in extraterrestrial samples, but the mechanisms accounting for their synthesis in space are not well understood. While electron-driven production of organic solids from gas mixtures reminiscent of the photosphere of the protosolar nebula (PSN; i.e., dominated by CO--N2--H2) successfully reproduced key specific features of the chondritic insoluble organic matter (e.g., elementary and isotopic signatures of chondritic noble gases), the molecular diversity of organic materials has never been investigated. Here, we report that a large range of biomolecules detected in meteorites and comets can be synthesized under conditions typical of the irradiated gas phase of the PSN at temperatures=800 K. Our results suggest that organic materials---including biomolecules---produced within the photosphere would have been widely dispersed in the protoplanetary disk through turbulent diffusion, providing a mechanism for the distribution of organic meteoritic precursors prior to any thermal/photoprocessing and subsequent modification bysecondary parent body processes. Using a numerical model of dust transport in a turbulent disk, we propose that organic materials produced in the photosphere of the disk would likely be associated with small dust particles, which are coupled to the motion of gas within the disk and therefore preferentially lofted into the upper layers of the disk where organosynthesis occurs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Boucher_etal2018,

title = {Spatial analysis of the atmospheric helium isotopic composition: Geochemical and environmental implications},

author = {C. Boucher and T. Lan and J. Mabry and D. V. Bekaert and P. G. Burnard and B. Marty},

doi = {10.1016/j.gca.2018.06.010},

year  = {2018},

date = {2018-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {237},

pages = {120--130},

abstract = {Spatial variations in the atmospheric helium isotopic composition (RA = 3He/4Heair = 1.39 texttimes 10−6) might be induced by localized and/or regional inputs of 3He and/or 4He into the air. It has been suggested that inputs of 4He from hydrocarbon exploitation may generate latitudinal variations in atmospheric 3He/4He. In order to test the possibility of such global variations, we performed high precision analyses of the helium isotopic composition (3He/4He) of sixteen air samples collected in 500 cc metal bottles around the world (79textdegreeN--75textdegreeS) between 2013 and 2015. In most cases, the 3He/4He of these air samples are indistinguishable from that of air sampled around Nancy (France) within ≤2texttenthousand (95% confidence interval). Only two air samples, collected at Dome C (Antarctica) and at Tokyo (Japan), exhibit statistically higher 3He/4He ratios interpreted as potential 3He excesses of (2.0 textpm 1.4)texttenthousand and (1.7 textpm 1.5)texttenthousand (95% confidence interval), respectively. Excesses such as these suggest that potential helium isotopic variations in air are likely lower than 4texttenthousand and might be generated temporarily by regional and/or local phenomenon (e.g. auroral precipitation, stratospheric to tropospheric exchanges). Thus, this study supports the use of the atmospheric helium isotopic ratio as an inter-laboratory He standard.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Boucher_etal2018_2,

title = {Atmospheric helium isotopic ratio from 1910 to 2016 recorded in stainless steel containers},

author = {C. Boucher and B. Marty and L. Zimmermann and R. Langenfelds},

doi = {10.7185/geochemlet.1804},

year  = {2018},

date = {2018-01-01},

journal = {Geochemical Perspectives Letters},

volume = {6},

pages = {23--27},

abstract = {The atmospheric helium isotope composition (RA=3He/4He air = 1.39 texttimes 10-6) could have varied over recent times due to anthropogenic activities. In order to check this possibility, we conducted high-precision helium isotope measurements of air trapped in various stainless steel containers from France (p\'{e}tanque balls, a float carburettor ; 1910--2016) and Cape Grim, Tasmania (archived air tanks ; 1978, 1988). We used a double collector mass spectrometer at the Centre de Recherches P\'{e}trographiques et G\'{e}ochimiques (CRPG, Nancy, France). We found a similar composition between the French and Cape Grim air samples. The temporal variation estimated from all samples including data previously published is not significant, with a trend of +0.002 textpm 0.024texttenthousand/yr over 106 years (2$sigma$). We suspect that the release of radiogenic 4He by fossil fuel exploitation could have been at least partly offset by the production of 3He (via the decay of 3H) from nuclear tests. This study supports the suitability of atmospheric helium as an inter-laboratory isotope standard.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Boucher_etal2018_3,

title = {Atmospheric helium isotope composition as a tracer of volcanic emissions: A case study of Erta Ale volcano, Ethiopia},

author = {C. Boucher and L. Tefang and B. Marty and P. G. Burnard and T. P. Fischer and D. Ayalew and J. Mabry and J. M. Moor and M. E. Zelenski and L. Zimmermann},

doi = {10.1016/j.chemgeo.2017.05.011},

year  = {2018},

date = {2018-01-01},

journal = {Chemical Geology},

volume = {480},

pages = {3--11},

abstract = {The composition of atmospheric helium is generally considered to be constant (3He/4He = 1.39 texttimes 10− 6) on a large spatial scale. However, local variations may arise in tectonically active areas due to focussed degassing of one of its two isotopes, for example degassing of mantle-derived 3He or crustal-derived 4He. If detected, such variations have the potential to trace open conduit degassing of magmatic bodies and/or diffusive emissions from volcanic and/or crustal sources. Here, we test the possibility of detecting such variations in the Afar region of north-eastern Ethiopia, which is located over a well-developed rift system. Special attention was paid to the Erta Ale volcanic edifice, where both magma lake activity and strong degassing occur. We conducted high-precision 3He/4He ratio measurements of air samples from this region using an analytical facility at the Centre de Recherches P\'{e}trographiques et G\'{e}ochimiques (CRPG), Nancy (France) that was specially designed for high-precision noble gas analyses.Within the precision of our measurements (0.2--0.4%, 95% confidence interval), the helium isotopic compositions of air from both the Afar rift zone and the crater zone of Erta Ale are similar to the composition of air collected at Brabois Park in Villers-les-Nancy, France (labelled here as RBB). An additional air sample collected in a large tank (500 cm3) in Afar in 2015 permitted replicate analysis (n = 8) and improved precision. The 3He/4He ratio of this additional sample was also identical to RBB within 0.19% (95% confidence interval, CI). However, a clear excess of 3He (1.32 textpm 0.64%, 95% CI, relative to RBB based on a weighted mean of two samples) was detected in air collected above the active lava lake located in the central pit crater of Erta Ale volcano. Such excess requires a 3He flux of 0.15 textpm 0.09 mol/yr from the crater lava lake to be sustained. A similar 3He flux of 0.12 textpm 0.06 mol/yr is calculated from SO2 flux measurements and fumerolic gas data obtained during the same field trip. At several sites in the rim of the Northern crater, we conducted soil flux measurements using an accumulation chamber. Both the CO2 contents and the helium isotope ratios increased over time within the chamber, allowing us to evaluate the soil CO2 and 3He fluxes outside the lava lake area. These fluxes were found to be minor ( 1%) compared to the lava lake flux. The CO2/3He ratio of (3.1 textpm 0.7) texttimes 109 of soil gases is comparable to that of the high temperature (1084 textdegreeC) fumaroles sited in the north pit crater. Using this ratio and our estimated 3He flux, we determined a CO2 flux of 4.6 textpm 3.0 texttimes 108 mol/yr for the lava lake, which is about 105 times lower than the global volcanic subaerial CO2 flux. Based on this pilot study, we suggest that 3He excesses in air could provide another means with which to evaluate the fluxes of CO2 and other volatile species in specific environments, such as highly active volcanic areas.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2018,

title = {Salinity of the Archaean oceans from analysis of fluid inclusions in quartz},

author = {B. Marty and G. Avice and D. V. Bekaert and M. W. Broadley},

doi = {10.1016/j.crte.2017.12.002},

year  = {2018},

date = {2018-01-01},

journal = {Comptes Rendus Geoscience},

volume = {350},

pages = {154--163},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mollex_etal2018,

title = {Tracing helium isotope compositions from mantle source to fumaroles at Oldoinyo Lengai volcano, Tanzania},

author = {G. Mollex and E. F\"{u}ri and P. Burnard and L. Zimmermann and G. Chazot and E. O. Kazimoto and B. Marty and L. France},

doi = {10.1016/j.chemgeo.2017.08.015},

year  = {2018},

date = {2018-01-01},

journal = {Chemical Geology},

volume = {480},

pages = {66--74},

abstract = {Oldoinyo Lengai is the only volcano on Earth currently erupting natrocarbonatites, of which the source and genesis remain controversial. Cognate xenoliths and fumaroles were sampled at the summit of Oldoinyo Lengai, and deep crustal xenoliths from Oltatwa maar, in 2010 and 2014, after the 2007--2008 sub-Plinian eruption. Thesummit cognate xenoliths provide direct information on the isotopic composition of the mid-crustal magma chamber that was active during the 2007--2008 explosive eruption. Cognate xenolith-hosted pyroxenes from Oldoinyo Lengai have an average 3He/4He =6.58 textpm 0.46 RA, similar to values from nearby silicate volcanoes(4.95--7.30 RA), and reflecting a sub-continental lithospheric mantle (SCLM) signature. This similarity implies that Oldoinyo Lengai carbonatites form from a similar mantle reservoir as the nearby silicate volcanoes. We identify SCLM, metasomatized by fluids/melts derived from the depleted convective mantle, as the common source of magmas in the Arusha volcanic province. Fumarole measurements highlight that fumarolic 3He/4He values have been relatively constant since at least 1988, indicating that dramatic changes to the crater region morphology during the 2007--2008 eruption did not affect the architecture of the hydrothermal system, which is probably connected to the crustal magma chamber(s). Moreover, the similarity between 3He/4He values from the mid-crustal magma chamber (6.58 textpm 0.46 RA) and fumaroles (7.31 textpm 0.24 RA) of Oldoinyo Lengai attests that helium is not subjected to atmospheric contamination or crustal assimilation during transport to the surface.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Rubin_etal2018,

title = {Krypton isotopes and noble gas abundances in the coma of comet 67P/Churyumov-Gerasimenko},

author = {M. Rubin and K. Altwegg and H. Balsiger and A. Bar-Nun and J. J. Berthelier and C. Briois and U. Calmonte and M. Combi and J. De Keyser and B. Fiethe and S. A. Fuselier and S. Gasc and T. I. Gobosi and K. C. Hansen and E. Kopp and A. Korth and D. Laufer and L. Le Roy and U. Mall and B. Marty and al},

year  = {2018},

date = {2018-01-01},

journal = {Science Advances},

volume = {4},

pages = {1--10},

abstract = {The Rosetta Orbiter Spectrometer for Ion and NeutralAnalysismass spectrometerDouble Focusing Mass Spectrometer on board the European Space Agencytextquoterights Rosetta spacecraft detected themajor isotopes of the noble gases argon, krypton, and xenon in the coma of comet 67P/Churyumov-Gerasimenko. Earlier, it was found that xenon exhibits anisotopic composition distinct from anywhere else in the solar system. However, argon isotopes, within error, were shown to be consistent with solar isotope abundances. This discrepancy suggested an additional exotic component of xenon in comet 67P/Churyumov-Gerasimenko. We show that krypton also exhibits an isotopiccomposition close to solar. Furthermore, we found the argon to krypton and the krypton to xenon ratios in the comet to be lower than solar, which is a necessity to postulate an addition of exotic xenon in the comet.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ruffine_etal2018,

title = {Multiple gas reservoirs are responsible for the gas emissions along the Marmara fault network},

author = {L. Ruffine and J. P. Donval and C. Croguennec and P. Burnard and H. Lu and Y. Germain and L. N. Legoix and L. Bignoin and N. M. Cagatay and B. Marty and D. Madre and M. Pitel-Roudaut and P. Henry and L. G\'{e}li},

doi = {10.1016/j.dsr2.2017.11.011},

year  = {2018},

date = {2018-01-01},

journal = {Deep-Sea Research II},

volume = {153},

pages = {48--60},

abstract = {On continental margins,upward migration of fluids from various sources and various subsurface accumulations, through the sedimentary column to the seafloor, leads to the development of cold seeps where chemical compounds are discharged into the water column. MarsiteCruise was undertaken in November 2014 to investigate the dynamics of cold seeps characterized by vigorous gas emissions in the Sea of Marmara (SoM).A previous paper published by Bourry et al. (2009) presented the gas geochemistry of three seeps sampled along three different segments in the SoM.Their findings showed that the seeps were sourced by three different reservoirs. In this paper, seventeen seeps were investigated to determine the gas sources, unravel reservoircontributions, and estimate their level of mixing. The molecular and stable isotope compositions of the gas compounds were determined to establish the empirical diagrams that usually allow to delineate source domains.The results provide insights into the complexities of source mixing within the sedimentary column of the SoM before emission of the gases into the water column.The seep gases originate from deep thermogenic or microbial hydrocarbon sources, or from a CO2-rich source. Microbial sources producing methane from primary methanogenesis have been identified in the Tekirda\u{g} and the \c{C}ınarcık basins. In addition, six different thermogenic reservoirs or six different pathways of migration are responsible for the supply of gas to the seeps on the highsand in the western basin. Five of them are undergoing biodegradation followed by secondary methanogenesis, there by providing additional sources of microbial methane to the seeps. Overall, the gases emitted by the seventeen seeps consist of variable mixtures of different components from two or three sources.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ruffine_etal2018_2,

title = {Multidisciplinary investigation on cold seeps with vigorous gas emissions in the Sea of Marmara (MarsiteCruise): Strategy for site detection and sampling and first scientific outcome},

author = {L. Ruffine and H. Ondreas and M. M. Blanc-Valleron and B. M. A. Teichert and and P. Burnard and B. Marty and D. Madre},

doi = {10.1016/j.dsr2.2018.03.006},

year  = {2018},

date = {2018-01-01},

journal = {Deep-Sea Research II},

volume = {153},

pages = {36--47},

abstract = {MarsiteCruise was undertaken in October/November 2014 in the Sea of Marmara to gain detailed insight into the fate of fluids migrating within the sedimentary column and partially released into the water column. The overall objective of the project was to achieve a more global understanding of cold-seep dynamics in the context of a major active strike-slip fault. Five remotely operated vehicle (ROV) dives were performed at selected areas along the North Anatolian Fault and inherited faults.To efficiently detect, select and sample the gas seeps, we applied an original procedure. It combines sequentially (1) the acquisition of ship-borne multibeam acoustic data from the water column prior to each dive to detect gas emission sites and to design the tracks of the ROV dives, (2) in situ and real-time Raman spectroscopy analysis of the gas stream, and (3) onboard determination of molecular and isotopic compositions of the collected gas bubbles. The in situ Raman spectroscopy was used as a decision-making tool to evaluate the need for continuing with the sampling of gases from the discovered seep, or to move to another one. Push cores were gathered to study buried carbonates and pore waters at the surficial sediment, while CTD-Rosette allowed collecting samples to measure dissolved-methane concentration within the water column followed by a comparison with measurements from samples collected with the submersible Nautile during the Marnaut cruise in 2007.Overall, the visited sites were characterized by a wide diversity of seeps. CO2- and oil-rich seeps were found at the westernmost part of the sea in the Tekirdag Basin, while amphipods, anemones and coral populated the sites visited at the easternmost part in the Cinarcik Basin. Methane-derived authigenic carbonates and bacterial mats were widespread on the seafloor at all sites with variable size and distributions. The measured methane concentrations in the water column were up to 377 $mu$mol, and the dissolved pore-water profiles indicated the occurrence of sulfate depleting processes accompanied with carbonate precipitation. The pore-water profiles display evidence of biogeochemical transformations leading to the fast depletion of seawater sulfate within the first 25-cm depth of the sediment. These results show that the North Anatolian Fault and inherited faults are important migration paths for fluids for which a significant part is discharged into the water column, contributing to the increase of methane concentration at the bottom seawater and favoring the development of specific ecosystems.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zimmermann_etal2018,

title = {A new all-metal induction furnace for noble gas extraction},

author = {L. Zimmermann and G. Avice and P. H. Blard and B. Marty and E. F\"{u}ri and P. G. Burnard},

doi = {10.1016/j.chemgeo.2017.09.018},

year  = {2018},

date = {2018-01-01},

journal = {Chemical Geology},

volume = {480},

pages = {86--92},

abstract = {A new all-metal induction furnace for extraction of all noble gases from pyroxenes, olivines, quartz or barites has been developed at CRPG. It differs in design from other induction furnaces in that the totality of the vacuum vessel is metallic and the induction coil, normally located outside the furnace, has been placed inside the vacuum vessel, with a special radio frequency power feedthrough welded onto a flange. The volume of the crucible is ≈15 cm3 and permits fusion of samples with a mass of up to 1 g. Samples are packed into a metal foil, loaded into a carousel, baked out before analysis, and then sequentially dropped into the Ta-crucible. The lowweight of the crucible (≈120 g) allows for short and efficient degassing cycles. When the furnace is pumped for the first time after samples loading, short cycles between 500 and 1800 textdegreeC at fast heating rates (≈400 textdegreeCtextperiodcenteredmin−1) are sufficient to achieve very low blanks. The durations of these cycles are range from 30 min for He to up to a few hours for Ne, Kr and Xe. Blanks of He, Kr and Xe (10 min heating durations) and Ne (20 min) in static vacuum are (1.6 textpm 1.0)texttimes10−15 mol 4He (T=1750 textdegreeC), (5.8 textpm 2.3)texttimes10−17 mol 20Ne (T=1500 textdegreeC), (2.1 textpm 0.3)texttimes10−18 mol 84Kr (T=1700 textdegreeC) and (4.4 textpm 0.4)texttimes10−18 mol 132Xe (T=1700 textdegreeC). Argon blanks have not yet been measured.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mousis_etal2018,

title = {Scientific rationale for Uranus and Neptune in situ explorations},

author = {O. Mousis and D. H. Atkinson and T. Cavali\'{e} and L. N. Fletcher and M. J. Amato and S. Aslam and F. Ferri and Renard and J.B. and T. Spilker and E. Venkatapathy and P. Wurz and K. Aplin and A. Coustenis and M. Deleuil and M. Dobrijevic and T. FOuchet and T. Guillot and P. Hartogh and T. Hewagama and M. D. Hofstadter and V. Hue and R. Hueso and J. P. Lebreton and E. Lellouch and J. Moses and G. S. Orton and J. C. Pearl and A. Sanchez-Lavega and A. Simon and O. Venot and J. H. Waite and R. K. Achterberg and S. Atreya and F. Billebaud and M. Blanc and F. Borget and B. Brugger and S. Charnoz and T. CHiavassa and V. Cottini and L. dtextquoterightHendecourt and G. Danger and T. Encrenaz and N. J. P. Gorius and L. Jorda and B. Marty},

doi = {10.1016/j.pss.2017.10.005},

year  = {2018},

date = {2018-01-01},

urldate = {2018-01-01},

journal = {Planetary and Space Science},

volume = {155},

pages = {12--40},

abstract = {The ice giants Uranus and Neptune are the least understood class of planets in our solar system but the most frequently observed type of exoplanets. Presumed to have a small rocky core, a deep interior comprising �`u70% heavy elements surrounded by a more dilute outer envelope of H2 and He, Uranus and Neptune are fundamentally different from the better-explored gas giants Jupiter and Saturn. Because of the lack of dedicated exploration missions, our knowledge of the composition and atmospheric processes of these distant worlds is primarily derived from remote sensing from Earth-based observatories and space telescopes. As a result, Uranustextquoterights and Neptunetextquoterights physical and atmospheric properties remain poorly constrained and their roles in the evolution of the Solar System not well understood. Exploration of an ice giant system is therefore a high-priority science objective as these systems (including the magnetosphere, satellites, rings, atmosphere, and interior) challenge our understanding of planetary formation and evolution. Here we describe the main scientific goals to be addressed by a future in situ exploration of an ice giant. An atmospheric entry probe targeting the 10-bar level, about 5 scale heights beneath the tropopause, would yield insight into two broad themes : i) the formation history of the ice giants and, in a broader extent, that of the Solar System, and ii) the processes at play in planetary atmospheres. The probe would descend under parachute to measure composition, structure, and dynamics, with data returned to Earth using a Carrier Relay Spacecraft as a relay station. In addition, possible mission concepts and partnerships are presented, and a strawman ice-giant probe payload is described. An ice-giant atmospheric probe could represent a significant ESA contribution to a future NASA ice-giant flagship mission.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Avice_etal2017,

title = {The origin and degassing history of the Earthtextquoterights atmosphere revealed by Archean xenon},

author = {G. Avice and B. Marty and R. Burgess},

doi = {10.1038/ncomms15455},

year  = {2017},

date = {2017-01-01},

journal = {Nature Communications},

abstract = {Xenon (Xe) is an exceptional tracer for investigating the origin and fate of volatile elements on Earth. The initial isotopic composition of atmospheric Xe remains unknown, as do the mechanisms involved in its depletion and isotopic fractionation compared with other reservoirs in the solar system. Here we present high precision analyses of noble gases trapped in fluid inclusions of Archean quartz (Barberton, South Africa) that reveal the isotopic composition of the paleo-atmosphere at E3.3 Ga. The Archean atmospheric Xe is massdependently fractionated by 12.9textpm2.4%utextdegree/textdegreetextdegree1 (textpm2s, s.d.) relative to the modern atmosphere. The lower than today 129Xe excess requires a degassing rate of radiogenic Xe from the mantle higher than at present. The primordial Xe component delivered to the Earthtextquoterights atmosphere is distinct from Solar or Chondritic Xe but similar to a theoretical component called U-Xe. Comets may have brought this component to the Earthtextquoterights atmosphere during the last stages of terrestrial accretion.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bekaert_etal2017,

title = {Stepwise heating of lunar anorthosites 60025, 60215, 65315 possibly reveals an indigenous noble gas component on the Moon},

author = {D. V. Bekaert and G. Avice and B. Marty and B. Henderson and M. S. Gudipati},

doi = {10.1016/j.gca.2017.08.041},

year  = {2017},

date = {2017-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {218},

pages = {114--131},

abstract = {Despite extensive effort during the last four decades, no clear signature of a lunar indigenous noble gas component has been found. In order to further investigate the possible occurrence of indigenous volatiles in the Moon, we have reanalyzed the noble gas and nitrogen isotopic compositions in three anorthosite samples. Lunar anorthosites 60025, 60215 and 65315 have the lowest exposure duration (textasciitilde2 Ma) among Apollo samples and consequently contain only limited cosmogenic (e.g.124,126Xe) and solar wind (SW) noble gases. Furthermore, anorthosites have negligible contributions of fissiogenic Xe isotopes because of their very low Pu and U contents. As observed in previous studies (Lightner and Marti, 1974; Leich and Niemeyer, 1975), lunar anorthosite Xe presents an isotopic composition very close to that of terrestrial atmospheric Xe, previously attributed to textquotelefttextquoteleftanomalous adsorptiontextquoterighttextquoteright of terrestrial Xe after sample return. The presumed atmospheric Xe contamination can only be removed by heating the samples at medium to high temperatures under vacuum, and is therefore different from common adsorption. To test this hypothesis, we monitored the adsorption of Xe onto lunar anorthositic powder using infrared reflectance spectroscopy. A clear shift in the anorthosite IR absorbance peaks is detected when comparing the IR absorbance spectra of the lunar anorthositic powder before and after exposure to a neutral Xe-rich atmosphere. This observation accounts for the chemical bonding (chemisorption) of Xe onto anorthosite, which is stronger than the common physical bonding (physisorption) and could account for the anomalous adsorption of Xe onto lunar samples. Our high precision Xe isotope analyses show slight mass fractionation patterns across 128--136 Xe isotopes with systematic deficits in the heavy Xe isotopes (mostly 136 Xe and marginally 134 Xe) that have not previously been observed. This composition could be the result of mixing between an irreversibly adsorbed terrestrial contaminant that is mostly released at high temperature and an additional signature. Solar Wind (SW) Xe contents, estimated from SW-Ne and SW-Ar concentrations and SW-Ne/Ar/Xe elemental ratios, do not support SW as the additional contribution. Using a x2 test, the latter is best accounted for by cometary Xe as measured in the coma of Comet 67P/Churyumov-Gerasimenko (Marty et al., 2017) or by the primordial U-Xe composition inferred to be the precursor of atmospheric Xe (Pepin, 1994; Avice et al., 2017). It could have been contributed to the lunar budget by volatile-rich bodies that participated to the building of the terrestrial atmosphere inventory (Marty et al., 2017).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DeKeyser_etal2017,

title = {Evidence for distributed gas sources of hydrogen halides in the coma of comet 67P/Churyumov-Gerasimenko},

author = {J. De Keyser and F. Dhooghe and K. Altwegg and H. Balsiger and J. J. Berthelier and C. Briois and U. Calmonte and G. Cessateur and M. Combi and E. E. B. Fiethe and S. A. Fuselier and S. Gasc and A. Gibbons and T. I. Gombosi and H. Gunell and M. H\"{a}ssig and L. Le Roy and R. Maggiolo and U. Mall and B. Marty and E. Neefs and H. R`eme and M. Rubin and T. S\'{e}mon and C. Y. Tzou and P. Wurz},

doi = {10.1093/mnras/stx2725},

year  = {2017},

date = {2017-01-01},

journal = {Monthly Notices of the Royal Astronomical Society},

volume = {469},

pages = {695--711},

abstract = {Rosetta has detected the presence of the hydrogen halides HF, HCl, and HBr in the coma of comet 67P/Churyumov--Gerasimenko. These species are known to freeze out on icy grains in molecular clouds. Analysis of the abundances of HF and HCl as a function of cometocentric distance suggests that these hydrogen halides are released both from the nucleus surface and off dust particles in the inner coma. We present three lines of evidence. First, the abundances of HF and HCl relative to the overall neutral gas in the coma appear to increase with distance, indicating that a net source must be present; since there is no hint at any possible parent species with sufficient abundances that could explain the observed levels of HF or HCl, dust particles are the likely origin. Second, the amplitude of the daily modulation of the halide-to-water density due to the rotation and geometry of 67Ptextquoterights nucleus and the corresponding surface illumination is observed to progressively diminish with distance and comet dust activity; this can be understood from the range of dust particle speeds well below the neutral gas expansion speed, which tends to smooth the coma density profiles. Third, strong halogen abundancechanges detected locally in the coma cannot be easily explained from composition changes at the surface, while they can be understood from differences in local gas production from the dust particles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kuga_etal2017,

title = {Processes of noble gas elemental and isotopic fractionations in plasma-produced organic solids: Cosmochemical implications},

author = {M. Kuga and G. Cernogora and Y. Marrocchi and L. Tissandier and B. Marty},

doi = {10.1016/j.gca.2017.08.031},

year  = {2017},

date = {2017-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {217},

pages = {219--230},

abstract = {The main carrier of primordial heavy noble gases in chondrites is thought to be an organic phase, known as phase Q, whose precise characterization has resisted decades of investigation. The Q noble gas component shows elemental and isotopicfractionation relative to the Solar, in favor of heavy elements and isotopes. These noble gas characteristics were experimentally simulated using a plasma device called the textquotelefttextquoteleftNebulotrontextquoterighttextquoteright. In this study, we synthesized thirteen solid organic samples by electron-dissociation of CO, in which a noble gas mixture was added. The analysis of their heavy noble gas (Ar, Kr and Xe) contents and isotopic compositions reveals enrichment in the heavy noble gas isotopes and elements relative to the light ones. The isotope fractionation is mass-dependent and is consistent with a mn-type law, where n 
 1. Based on a plasma model, wepropose that the ambipolar diffusion of ions in the ionized CO gas medium is at the origin of the noble gas isotopic fractionation. In addition, the elemental fractionation of experimental and chondritic samples can be accounted for by the Saha law of plasma equilibrium, which does not depend on the respective noble gas masses but rather on their ionization potentials. Our results suggest that the Q noble gases were trapped into growing organic particles starting from solar gases that were fractionated in an ionized medium by ambipolar diffusion and Saha processes. This would imply that both the formation of chondritic organic matter and the trapping of noble gases took place simultaneously in the ionized areas of the protoplanetary disk.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2017,

title = {Xenon isotopes in 67P/Churyumov- Gerasimenko show that comets contributed to Earthtextquoterights atmosphere},

author = {B. Marty and K. Altwegg and Balsigern H. and A. Bar-Nun and D. V. Bekaert and J. J. Berthelier and A. Bieler and C. Briois and U. Calmonte and M. Combi and J. De Keyser and B. Fiethe and S. A. Fuselier and S. Gasc and T. I. Gombosi and K. C. Hansen and M. H\"{a}ssig and A. J\"{a}ckel and E. Kopp and A. Korth and L. Le Roy and U. Mall and O. Mousis and T. Owen and H. R`eme and M. Rubin and T. S\'{e}mon and C. Y. Tzou and J. H. Waite and P. Wurz},

doi = {10.1126/science.aal3496},

year  = {2017},

date = {2017-01-01},

journal = {Science},

number = {356},

pages = {1069--1072},

abstract = {The origin of cometary matter and the potential contribution of comets to inner-planet atmospheres are long-standing problems. During a series of dedicated low-altitude orbits, the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) on the Rosetta spacecraft analyzed the isotopes of xenon in the coma of comet 67P/Churyumov-Gerasimenko. The xenon isotopic composition shows deficits in heavy xenon isotopes and matches that of a primordial atmospheric component. The present-day Earth atmosphere contains 22 textpm 5% cometary xenon, in addition to chondritic (or solar) xenon.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pitre_etal2017,

title = {New measurement of the Boltzmann constant k by acoustic thermometry of helium-4 gas},

author = {L. Pitre and F. Sparasci and L. Risegari and C. Guianvarctextquoterighth and C. Martin and M. E. Himbert and M. D. Plimmer and A. Allard and B. Marty and P. A. Giuliano Albo and B. Gao and M. R. Moldover and J. B. Mehl},

doi = {10.1088/1681-7575/aa7bf5},

year  = {2017},

date = {2017-01-01},

journal = {Metrologia},

volume = {54},

pages = {856--873},

abstract = {The SI unit of temperature will soon be redefined in terms of a fixed value of the Boltzmann constant k derived from an ensemble of measurements worldwide. We report on a new determination of k using acoustic thermometry of helium-4 gas in a 3 l volume quasi-spherical resonator. The method is based on the accurate determination of acoustic and microwave resonances to measure the speed of sound at different pressures. We find for the universal gas constant Rthinspacethinspace=thinspacethinspace8.314 4614(50) Jcenterdotmol−1centerdotK−1. Using the current best available value of the Avogadro constant, we obtain kthinspacethinspace=thinspacethinspace1.380thinspace648thinspace78(83)thinspacethinspacetexttimesthinspacethinspace10−23 JcenterdotK−1 with u(k)/kthinspacethinspace=thinspacethinspace0.60thinspacethinspacetexttimesthinspacethinspace10−6, where the uncertainty u is one standard uncertainty corresponding to a 68% confidence level. This value is consistent with our previous determinations and with that of the 2014 CODATA adjustment of the fundamental constants (Mohr et al 2016 Rev. Mod. Phys. 88 035009), within the standard uncertainties. We combined the present values of k and u(k) with earlier values that were measured at LNE. Assuming the maximum possible correlations between the measurements, (k present/textlanglektextranglethinspacethinspace−thinspacethinspace1)thinspacethinspace=thinspacethinspace0.07thinspacethinspacetexttimesthinspacethinspace10−6 and the combined u r (k) is reduced to 0.56thinspacethinspacetexttimesthinspacethinspace10−6. Assuming minimum correlations, (k present/textlanglektextranglethinspacethinspace−thinspacethinspace1)thinspacethinspace=thinspacethinspace0.10thinspacethinspacetexttimesthinspacethinspace10−6 and the combined u r (k) is reduced to 0.48thinspacethinspacetexttimesthinspacethinspace10−6.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dhooghe_etal2017,

title = {Halogens as tracers of protosolar nebula material in comet 67P/Churyumov--Gerasimenko},

author = {F. Dhooghe and K. Altwegg and C. Briois and H. Balsiger and J. J. Berhelier and U. Calmonte and G. Cessateur and M. Combi and E. Equeter and B. Fiethe and N. Fray and S. Fuselier and S. Gasc and A. Gibbons and T. Gombosi and H. Gunell and M. Hassig and M. Hilchenbach and L. Le Roy and R. Maggiolo and U. Mall and B. Marty},

doi = {10.1093/mnras/stx1911},

year  = {2017},

date = {2017-01-01},

urldate = {2017-01-01},

journal = {Monthly Notices of the Royal Astronomical Society},

volume = {472},

number = {2},

pages = {1336--1345},

abstract = {We report the first in situ detection of halogens in a cometary coma, that of 67P/Churyumov-Gerasimenko. Neutral gas mass spectra collected by the European Space Agencytextquoterights Rosetta spacecraft during four periods of interest from the first comet encounter up to perihelion indicate that the main halogen-bearing compounds are HF, HCl and HBr. The bulk elemental abundances relative to oxygen are �`u8.9 texttimes 10−5 for F/O, �`u1.2 texttimes 10−4 for Cl/O and �`u2.5 texttimes 10−6 for Br/O, for the volatile fraction of the comet. The cometary isotopic ratios for 37Cl/35Cl and 81Br/79Br match the Solar system values within the error margins. The observations point to an origin of the hydrogen halides in molecular cloud chemistry, with frozen hydrogen halides on dust grains, and a subsequent incorporation into comets as the cloud condensed and the Solar system formed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mousis_etal2017,

title = {Impact of radiogenic heating on the formation conditions of Comet 67P/Churyumov--Gerasimenko},

author = {O. Mousis and A. Drouard and P. Vernazza and J. I. Lunine and M. Monnereau and R. Maggiolo and K. Altwegg and H. Balsiger and J. J. Berthelier and G. Cessateur and J. De Keyser and S. A. Fuselier and S. Gasc and A. Korth and T. Le Deun and U. Mall and B. Marty},

doi = {10.3847/2041-8213/aa6839},

year  = {2017},

date = {2017-01-01},

urldate = {2017-01-01},

journal = {The Astrophysical Journal Letters},

volume = {839},

number = {1},

abstract = {Because of the high fraction of refractory material present in comets, the heat produced by the radiogenic decay of elements such as aluminum and iron can be high enough to induce the loss of ultravolatile species such as nitrogen, argon, or carbon monoxide during their accretion phase in the protosolar nebula (PSN). Here, we investigate how heat generated by the radioactive decay of 26Al and 60Fe influences the formation of comet 67P/Churyumov--Gerasimenko, as a function of its accretion time and the size of its parent body. We use an existing thermal evolution model that includes various phase transitions, heat transfer in the ice-dust matrix, and gas diffusion throughout the porous material, based on thermodynamic parameters derived from Rosetta observations. Two possibilities are considered: either, to account for its bilobate shape, 67P/Churyumov--Gerasimenko was assembled from two primordial textasciitilde2 km sized planetesimals, or it resulted from the disruption of a larger parent body with a size corresponding to that of comet Hale--Bopp (textasciitilde70 km). To fully preserve its volatile content, we find that either 67P/Churyumov--Gerasimenkotextquoterights formation was delayed between textasciitilde2.2 and 7.7 Myr after that of Ca--Al-rich Inclusions in the PSN or the comettextquoterights accretion phase took place over the entire time interval, depending on the primordial size of its parent body and the composition of the icy material considered. Our calculations suggest that the formation of 67P/Churyumov--Gerasimenko is consistent with both its accretion from primordial building blocks formed in the nebula or from debris issued from the disruption of a Hale--Bopp-like body.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Altwegg_etal2016,

title = {Prebiotic chemicals---amino acid and phosphorus--- in the coma of comet 67P/Churyumov-Gerasimenko},

author = {K. Altwegg and H. Balsiger and A. Bar-Nun and J. J. Berthelier and A. Bieler and P. Bochsler and C. Briois and U. Calmonte and M. Combi and H. Cottin and J. De Keyser and F. Dhooghe and B. Fiethe and S. A. Fuselier and S. Gasc and T. I. Gombosi and K. C. Hansen and M. Haessig and A. J^ackel and E. Kopp and A. Korth and L. Le Roy and U. Mall and B. Marty and O. Mousis and T. Owen and H. R`eme and M. Rubin and T. S\'{e}mon and C. Y. Tzou and J. H. Waite and P. Wurz},

doi = {10.1126/sciadv.1600285},

year  = {2016},

date = {2016-01-01},

journal = {Science Advances},

abstract = {The importance of comets for the origin of life on Earth has been advocated for many decades. Amino acids are key ingredients in chemistry, leading to life as we know it. Many primitive meteorites contain amino acids, and it is generally believed that these are formed by aqueous alterations. In the collector aerogel and foil samples of the Stardust mission after the flyby at comet Wild 2, the simplest form of amino acids, glycine, has been found together with precursor molecules methylamine and ethylamine. Because of contamination issues of the samples, a cometary origin was deduced from the 13C isotopic signature. We report the presence of volatile glycine accompanied by methylamine and ethylamine in the coma of 67P/Churyumov-Gerasimenko measured by the ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) mass spectrometer, confirming theStardust results. Together with the detection of phosphorus and a multitude of organic molecules, this result demonstrates that comets could have played a crucial role in the emergence of life on Earth.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Caracausi_etal2016,

title = {Chondritic xenon in the Earthtextquoterights mantle},

author = {A. Caracausi and G. Avice and P. Burnard and E. F\"{u}ri and B. Marty},

doi = {oi:10.1038/nature17434},

year  = {2016},

date = {2016-01-01},

journal = {Nature},

number = {533},

pages = {82--85},

abstract = {Noble gas isotopes are powerful tracers of the origins of planetary volatiles, and the accretion and evolution of the Earth. The compositions of magmatic gases provide insights into the evolution of the Earthtextquoterights mantle and atmosphere1. Despite recent analytical progress in the study of planetary materials, and mantle-derived gases the possible dual origin1, of the planetary gases in the mantle and the atmosphere remains unconstrained. Evidence relating to the relationship between the volatiles within our planet and the potential cosmochemical end-members is scarce. Here we show, using high-precision analysis of magmatic gas from the Eifel volcanic area (in Germany), that the light xenon isotopes identify a chondritic primordial component that differs from the precursor of atmospheric xenon. This is consistent with an asteroidal origin for the volatiles in the Earthtextquoterights mantle, and indicates that the volatiles in the atmosphere and mantle originated from distinct cosmochemical sources. Furthermore, our data are consistent with the origin of Eifel magmatism being a deep mantle plume. The corresponding mantle source has been isolated from the convective mantle since about 4.45 billion years ago, in agreement with models that predict the early isolation of mantle domains. Xenon isotope systematics support a clear distinction between mid-ocean-ridge and continental or oceanic plume sources, with chemical heterogeneities dating back to the Earthtextquoterights accretion. The deep reservoir now sampled by the Eifel gas had a lower volatile/refractory (iodine/plutonium) composition than the shallower mantle sampled by mid-ocean-ridge volcanism, highlighting the increasing contribution of volatile-rich material during the first tens of millions of years of terrestrial accretion.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Li_etal2016,

title = {Nitrogen isotope fractionation during terrestrial core-mantle separation},

author = {Y. Li and B. Marty and S. Shcheka and L. Zimmermann and H. Keppler},

doi = {10.7185/geochemlet.1614},

year  = {2016},

date = {2016-01-01},

journal = {Geochemical Perspectives Letters},

volume = {2},

pages = {138--147},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Luspay-Kuti_etal2016,

title = {The presence of clathrates in comet 67P/Churyumov-Gerasimenko},

author = {A. Luspay-Kuti and O. Mousis and M. H\"{a}ssig and S. A. Fuselier and J. I. Lunine and B. Marty and K. E. Mandt and P. Wurz and M. Rubin},

doi = {10.1126/sciadv.1501781},

year  = {2016},

date = {2016-01-01},

journal = {Science Advances},

abstract = {Cometary nuclei are considered to most closely reflect the composition of the building blocks of our solar system. As such, comets carry important information about the prevalent conditions in the solar nebula before and after planet formation. Recent measurements of the time variation of major and minor volatile species in the coma of the Jupiter family comet 67P/Churyumov-Gerasimenko (67P) by the ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) instrument onboard Rosetta provide insight into the possible origin of this comet. The observed outgassing pattern indicates that the nucleus of 67P contains crystalline ice, clathrates, and other ices. The observed outgassing is not consistent with gas release from an amorphous ice phase with trapped volatile gases. If thebuilding blocks of 67P were formed from crystalline ices and clathrates, then 67P would have agglomerated from ices that were condensed and altered in the protosolar nebula closer to the Sun instead of more pristine ices originating from the interstellar medium or the outskirts of the disc, where amorphous ice may dominate.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mall_etal2016,

title = {High-time resolution in situ investigation of major cometary volatiles around 67P/C_G at 3.1-2.3 au measured with ROSINA-RTOF},

author = {U. Mall and K. Altwegg and H. Balsiger and A. Bar-Nun and J. J. Berthelier and A. Bieler and P. Bochsler and C. Briois and U. Calmonte and M. Combi and B. Dabrowski and J. De Keyser and F. Dhooghe and B. Fiethe and S. A. Fuselier and A. Galli and P. Garnier and S. Gasc and T. I. Gombosi and K. C. Hansen and M. H\"{a}ssig and M. Hoang and A. J\"{a}ckel and E. Kopp and A. Korth and L. Le Roy and B. Magee and B. Marty and O. Mousis and H. R`eme and M. Rubin and T. S\'{e}mon and C. Y. Tzou and J. H. Waite and P. Wurz},

doi = {10.3847/0004-637X/819/2/126},

year  = {2016},

date = {2016-01-01},

journal = {The Astophysical Journal},

volume = {819},

number = {126},

abstract = {Comets considered to be pristine objects contain key information about the early formation of the solar system. Their volatile components can provide clues about the origin and evolution of gases and ices in the comets. Measurements with ROSINA/RTOF at 67P/Churyumov--Gerasimenko have now allowed, for the first time, adirect in situ high-time resolution measurement of the most abundant cometary molecules originating directly from a comettextquoterights nucleus over a long time-period, much longer than any previous measurements at a close distance to a comet between 3.1 and 2.3 au. We determine the local densities of H2O, CO2, and CO, and investigate their variabilities.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty2016,

title = {In Memory of Peter G. Burnard (1965-2015)},

author = {B. Marty},

year  = {2016},

date = {2016-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {174},

pages = {360--361},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2016,

title = {Origins of volatile elements (H, C, N, noble gases) on Earth and Mars in light of recent results from the ROSETTA cometary mission},

author = {B. Marty and G. Avice and Y. Sano and K. Altwegg and H. Balsiger and M. H\"{a}ssig and A. Morbidelli and O. Mousis and M. Rubin},

doi = {10.1016/j.epsl.2016.02.031},

year  = {2016},

date = {2016-01-01},

journal = {Earth and Planetary Science Letters},

volume = {441},

pages = {91--102},

abstract = {Recent measurements of the volatile composition of the coma of Comet 67P/Churyumov--Gerasimenko (hereafter 67P) allow constraints to be set on the origin of volatile elements (water, carbon, nitrogen, noble gases) in inner planetstextquoteright atmospheres. Analyses by the ROSINA mass spectrometry system onboard the Rosetta spacecraft indicate that 67P ice has a D/H ratio three times that of the ocean value (Altwegg et al., 2015)and contains significant amounts of N2, CO, CO2, and importantly, argon (Balsiger et al., 2015). Here we establish a model of cometary composition based on literature data and the ROSINA measurements. From mass balance calculations, and provided that 67P is representative of the cometary ice reservoir, we conclude that the contribution of cometary volatiles to the Earthtextquoterights inventory was minor for water (≤1%), carbon (≤1%), and nitrogen species (a few % at most). However, cometary contributions to the terrestrial atmosphere may have been significant for the noble gases. They could have taken place towards the end of the main building stages of the Earth, after the Moon-forming impact and during either a late veneer episode or, more probably, the Terrestrial Late Heavy Bombardment around 4.0--3.8 billion years (Ga) ago. Contributions from the outer solar system via cometary bodies could account for the dichotomy of the noble gas isotope compositions, in particular xenon, between the mantle and the atmosphere. A mass balance based on 36Ar and organics suggests that the amount of prebiotic material delivered by comets could have been quite considerable -- equivalent to the present-day mass of the biosphere. On Mars, several of the isotopic signatures of surface volatiles (notably the high D/H ratios) are clearly indicative of atmospheric escape processes. Nevertheless, we suggest that cometary contributions after the major atmospheric escape events, e.g., during a Martian Late Heavy Bombardment towards the end of the Noachian era, could account for the Martian elemental C/N/36Ar ratios, solar-like krypton isotope composition and high 15N/14N ratios. Taken together, these observations are consistent with the volatiles of Earth and Mars being trapped initially from the nebular gas and local accreting material, then progressively added to by contributions from wet bodies from increasing heliocentric distances. Overall, no unified scenario can account for all of the characteristics of the inner planet atmospheres. Advances in this domain will require precise analysis of the elemental and isotopic compositions of comets and therefore await a cometary sample return mission.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Meier_etal2016,

title = {Mercury (Hg) in meteorites: Variations in abundance, thermal release profile, mass-dependent and mass-independent isotopic fractionation},

author = {M. Meier and C. Cloquet and B. Marty},

doi = {10.1016/j.gca.2016.03.007},

year  = {2016},

date = {2016-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {182},

pages = {55--72},

abstract = {We have measured the concentration, isotopic composition and thermal release profiles of Mercury (Hg) in a suite of meteorites, including both chondrites and achondrites. We find large variations in Hg concentration between different meteorites (ca. 10 ppb to 14,000 ppb), with the highest concentration orders of magnitude above the expected bulk solar system silicates value. From the presence of several different Hg carrier phases in thermal release profiles (150--650 textdegreeC), we argue that these variations are unlikely to be mainly due to terrestrial contamination. The Hg abundance of meteorites shows no correlation with petrographic type, or mass-dependent fractionation of Hg isotopes. Most carbonaceous chondrites show massindependent enrichments in the odd-numbered isotopes 199Hg and 201Hg. We show that the enrichments are not nucleosynthetic,as we do not find corresponding nucleosynthetic deficits of 196Hg. Instead, they can partially be explained by Hg evaporation and redeposition during heating of asteroids from primordial radionuclides and late-stage impact heating.Non-carbonaceous chondrites, most achondrites and the Earth do not show these enrichments in vapor-phase Hg. All meteorites studied here have however isotopically light Hg (d202Hg = �`u-7 to -1) relative to the Earthtextquoterights average crustal values, which could suggest that the Earth has lost a significant fraction of its primordial Hg. However, the late accretion of carbonaceous chondritic material on the order of �`u2%, which has been suggested to account for the water, carbon, nitrogen and noble gas inventories of the Earth, can also contribute most or all of the Earthtextquoterights current Hg budget. In this case, the isotopically heavy Hg of the Earthtextquoterights crust would have to be the result of isotopic fractionation between surface and deep-Earth reservoirs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mousis_etal2016,

title = {A protosolar nebula origin for the ices agglomerated by comet 67P/Churyumov-Gerasimenko},

author = {O. Mousis and J. I. Lunine and A. Luspay-Kuti and T. Guillot and B. Marty and M. Ali-Dib and P. Wurz and K. Altwegg and A. Bieler and M. H\"{a}ssig and M. Rubin and P. Vernazza and J. H. Waite},

doi = {10.3847/2041-8205/819/2/L33},

year  = {2016},

date = {2016-01-01},

journal = {The Astrophysical Journal Letters},

volume = {819},

number = {L33},

abstract = {The nature of the icy material accreted by comets during their formation in the outer regions of the protosolar nebula (PSN) is a major open question in planetary science. Some scenarios of comet formation predict that these bodies agglomerated from crystalline ices condensed in the PSN. Concurrently, alternative scenarios suggest that comets accreted amorphous ice originating from the interstellar cloud or from the very distant regions of the PSN. On the basis of existing laboratory and modeling data, we find that the N2/CO and Ar/CO ratios measured in thecoma of the Jupiter-family comet 67P/Churyumov--Gerasimenko by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis instrument on board the European Space Agencytextquoterights Rosetta spacecraft match those predicted for gases trapped in clathrates. If these measurements are representative of the bulk N2/CO and Ar/CO ratios in 67P/Churyumov--Gerasimenko, it implies that the ices accreted by the comet formed in the nebula and do not originate from the interstellar medium, supporting the idea that the building blocks of outer solar system bodies have been formed from clathrates and possibly from pure crystalline ices. Moreover, because 67P/Churyumov--Gerasimenko is impoverished in Ar and N2, the volatile enrichments observed in Jupitertextquoterights atmosphere cannot be explained solely via the accretion of building blocks with similar compositions and require an additional delivery source. A potential source may be the accretion of gas from the nebula that has been progressively enriched in heavy elements due to photoevaporation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Groussin_etal2016,

title = {THERMAP: a mid-infrared spectro-imager for space missions to small bodies in the inner solar system},

author = {O. Groussin and J. Licandro and J. Helbert and J. L. Reynaud and B. Marty},

year  = {2016},

date = {2016-01-01},

urldate = {2016-01-01},

journal = {Experimental Astronomy},

volume = {41},

pages = {95--115},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Avice_etal2015,

title = {A comprehensive study of noble gases and nitrogen in textquotelefttextquoteleftHypatiatextquoterighttextquoteright, a diamond-rich pebble from SW Egypt},

author = {G. Avice and M. Meir and B. Marty and R. Wieler and J. D. Kramers and F. Langenhorst and P. Cartigny and C. Maden and L. Zimmermann and M. A. G Andreoli},

doi = {10.1016/j.epsl.2015.10.013},

year  = {2015},

date = {2015-01-01},

journal = {Earth and Planetary Science Letters},

volume = {432},

pages = {243--253},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Balsiger_etal2015,

title = {Detection of argon in the coma of comet 67P/Churyumov-Gerasimenko},

author = {H. Balsiger and K. Altwegg and A. Bar-Nun and J. J. Berthelier and A. Bieler and P. Bochsler and C. Briois and U. Calmonte and M. Combi and J. De Keyser and P. Eberhardt and B. Fiethe and S. A. Fuselier and S. Gasc and T. I. Gombosi and K. C. Hansen and M. H\"{a}ssig and A. J\"{a}ckel and E. Kopp and A. Korth and L. Le Roy and U. Mall and B. Marty and O. Mousis and T. Owen and H. R`eme and M. Rubin and T. S\'{e}mon and C. Y. Tzou and J. H. Waite and P. Wurz},

doi = {10.1126/sciadv.1500377},

year  = {2015},

date = {2015-01-01},

journal = {Science Advances},

volume = {1},

number = {8},

abstract = {Comets have been considered to be representative of icy planetesimals that may have contributed a significant fraction of the volatile inventory of the terrestrial planets. For example, comets must have brought some water to Earth. However, the magnitude of their contribution is still debated. We report the detection of argon and its relation to the water abundance in the Jupiter family comet 67P/Churyumov-Gerasimenko by in situ measurement of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) mass spectrometer aboard the Rosetta spacecraft. Despite the very low intensity of the signal, argon is clearly identified by the exact determination of the mass of the isotope 36Ar and by the 36Ar/38Ar ratio. Because of time variability and spatial heterogeneity of thecoma, only a range of the relative abundance of argon to water can be given. Nevertheless, this range confirms that comets of the type 67P/Churyumov-Gerasimenko cannot be the major source of Earthtextquoterights major volatiles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bieler_etal2015,

title = {Abundant molecular oxygen in the coma of comet 67P/Churyumov--Gerasimenko},

author = {A. Bieler and K. Altwegg and H. Balsiger and A. Bar-Nun and J. J. Berthelier and P. Bochsler and U. Calmonte and M. Combi and J. De Keyser and F. Dhooghe and B. Fiethe and S. A. Fuselier and S. Gasc and T. I. Gombosi and K. C. Hansen and M. H\"{a}ssig and A. J\"{a}ckel and E. Kopp and A. Korth and L. Le Roy and U. Mall and R. Maggiolo and B. Marty and O. Mousis and T. Owen and H. R`eme and M. Rubin and T. S\'{e}mon and C. Y. Tzou and J. H. Waite and C. Walsh and P. Wurz},

doi = {doi:10.1038/nature15707},

year  = {2015},

date = {2015-01-01},

journal = {Nature},

volume = {526},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fri_etal2015,

title = {Constraints on the origin of nitrogen in lunar basalts: Coupled nitrogen noble gas analyses},

author = {E. F\"{u}ri and P. H. Barry and L. Taylor and B. Marty},

year  = {2015},

date = {2015-01-01},

journal = {Earth and Planetary Science Letters},

volume = {431},

pages = {195--205},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fri_etal2015_2,

title = {Evidence for an early nitrogen isotopic evolution in the solar nebula from volatile analyses of a CAI from the CV3 chondrite NWA 8616},

author = {E. F\"{u}ri and M. Chaussidon and B. Marty},

doi = {10.1016/j.gca.2015.01.004},

year  = {2015},

date = {2015-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {153},

pages = {183--201},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fri+Marty2015,

title = {Nitrogen isotope variations in the solar system},

author = {E. F\"{u}ri and B. Marty},

year  = {2015},

date = {2015-01-01},

journal = {Nature Geoscience},

volume = {8},

pages = {515--522},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hssig_etal2015,

title = {Time variability and heterogeneity in the coma of 67P/Churyumov-Gerasimenko},

author = {M. H\"{a}ssig and K. Altwegg and H. Balsiger and J. J. Berthelier and A. Bieler and P. Bochsler and C. Briois and U. Calmonte and M. Combi and J. De Keyser and P. Eberhardt and B. Fiethe and S. A. Fuselier and M. Galand and S. Gasc and T. I. Gombosi and K. C. Hansen and A. J\"{a}ckel and H. U. Keller and E. Kopp and A. Korth and E. K\"{u}hrt and L. Le Roy and U. Mall and B. Marty and O. Moisis and E. Neefs and T. Owen and H. R`eme and M. Rubin and T. S\'{e}mon and C. Tornow and C. Y. Tzou and J. H. Waite and P. Wurz},

year  = {2015},

date = {2015-01-01},

journal = {Science},

volume = {347},

number = {6220},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Altwegg_etal2014,

title = {67P/Churyumov-Gerasimenko, a Jupiter family comet with a high D/H ratio},

author = {K. Altwegg and H. Balsiger and A. Bar-Nun and J. J. Berthelier and A. Bieler and P. Bochsler and C. Briois and U. Calmonte and M. Combi and J. De Keyser and P. Eberhardt and B. Fiethe and S. Fuselier and S. Gasc and T. I. Gombosi and K. C. Hansen and M. Hassig and A. J\"{a}ckel and E. Kopp and A. Korth and L. LeRoy and U. Mall and B. Marty and O. Mousis and E. Neefs and T. Owen and H. R`ene and M. Rubin and T. S\'{e}mon and C. Y. Tzou and H. Waite and P. Wurz},

doi = {10.1126/science.1261952},

year  = {2014},

date = {2014-01-01},

journal = {SciencExpress},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Avice+Marty2014,

title = {The iodine--plutonium--xenon age of the Moon--Earth system revisited},

author = {G. Avice and B. Marty},

doi = {10.1098/rsta.2013.0260},

year  = {2014},

date = {2014-01-01},

journal = {Philiosphical Transactions of the Royal Society A-Mathematical Physical and Engineering Sciences},

volume = {372},

number = {2024},

abstract = {Iodine--plutonium--xenon isotope systematics have been used to re-evaluate time constraints on the early evolution of the Earth--atmosphere system and, by inference, on the Moon-forming event. Two extinct radionuclides (129I, T1/2=15.6thinspaceMa and 244Pu, T1/2=80thinspaceMa) have produced radiogenic 129Xe and fissiogenic 131−136Xe, respectively, within the Earth, the related isotope fingerprints of which are seen in the compositions of mantle and atmospheric Xe. Recent studies of Archaean rocks suggest that xenon atoms have been lost from the Earthtextquoterights atmosphere and isotopically fractionated during long periods of geological time, until at least the end of the Archaean eon. Here, we build a model that takes into account these results. Correction for Xe loss permits the computation of new closure ages for the Earthtextquoterights atmosphere that are in agreement with those computed for mantle Xe. The corrected Xe formation interval for the Earth--atmosphere system is Embedded ImagethinspaceMa after the beginning of Solar System formation. This time interval may represent a lower limit for the age of the Moon-forming impact.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fri_etal2014,

title = {New evidence for chondritic lunar water from combined D/H and noble gas analyses of single Apollo 17 volcanic glasses},

author = {E. F\"{u}ri and E. Deloule and A. Gurenko and B. Marty},

doi = {10.1016/j.icarus.2013.10.029},

year  = {2014},

date = {2014-01-01},

journal = {Icarus},

volume = {229},

pages = {109--120},

abstract = {In order to assess the proportion of solar, cosmogenic, and indigenous water (hydrogen) trapped in individual Ti-rich lunar volcanic glasses (LVGs) from the 74002 core obtained during the Apollo 17 mission, we coupled ion microprobe measurements of water abundances and D/H ratios with CO2 laser extraction-static mass spectrometry analyses of noble gases (He, Ne, Ar). The large (300--400 lm in diameter) LVGs studied here contain a small amount of solar wind (SW) volatiles implanted at the grain surfaces, as indicated by the small concentrations of solar helium and neon that represent 65% of the respective totalnoble gas abundances. The large proportion of volume-correlated cosmogenic gases reflects an exposure duration of 28 Ma, on average, of the glasses at the lunar surface. Hydrogen abundances determined in the grain interiors of glassy and partially-crystalline LVGs are equivalent to between 6.5 and 54.3 ppm H2O. Based on the noble gas exposure ages, the correction of the measured hydrogen isotope composition for in situ production of cosmogenic deuterium by spallation reactions varies between 5texttenthousandto 254texttenthousandfor the different grains. Corrected dD values range from +38texttenthousand to +809texttenthousand in the LVGs and are anti-correlated with the water content, consistent with extensive hydrogen isotope fractionation during kinetic H2 lossfrom a lunar melt with an inferred initial isotope signature of the order of 100texttenthousand and a water content of 100--300 ppm. The detection of water in these primitive lunar melts confirms the presence of a nonanhydrous mantle reservoir within the Moon. Furthermore, our results reveal that the hydrogen isotope composition of water in the melt source of the 74002 LVGs is similar to that of carbonaceous chondrites. These observations indicate that the contribution of deuterium-enriched cometary water to the Earth-- Moon system is negligible.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hbrard+Marty2014,

title = {Coupled noble gas--hydrocarbon evolution of the early Earth atmosphere upon solar UV irradiation},

author = {E. H\'{e}brard and B. Marty},

doi = {10.1016/j.epsl.2013.10.022},

year  = {2014},

date = {2014-01-01},

journal = {Earth and Planetary Science Letters},

volume = {385},

pages = {40--48},

abstract = {Using a new photochemical model of the Earthtextquoterights early atmosphere, the relationship between noble gas photoionization and organic photochemistry has been investigated from the Archean eon to the present day. We have found that the enhanced UV emission of the young Sun triggered a peculiar atmospheric chemistry in a CH4-rich early atmosphere that resulted in the increased formation of an organic haze, similar to the preliminary results of a previous study (Ribas et al., 2010). We have investigated the interaction between this haze and noble gases photoionized by the UV light from the younger Sun. Laboratory experiments have shown indeed that ionized xenon trapping into organics (1) is more efficient that other ionized noble gases trapping and (2) results in a significant enrichment of heavy xenon isotopes relative to the light ones (e.g., Frick et al., 1979; Marrocchi et al., 2011). We find moreover preferential photoionization of xenon that peaks at an altitude range comparable to that of the organic haze formation, in contrast to other noble gases. Trapping and fractioning of ionized xenon in the organic haze could therefore have been far more efficient than for other noble gases, and could have been particularly effective throughout the Archean eon, since the UV irradiation flux from the young Sun was expected to be substantially higher than today (Ribas et al., 2010; Claire et al., 2012). Thus we suspect that the unique isotopic fractionation of atmospheric xenon and its elemental depletion in the atmosphere relative to other noble gases, compared to potential cosmochemical components, could have resulted from a preferential incorporation of the heaviest xenon isotopes into organics. A fraction of atmospheric xenon could have been continuously trapped in the forming haze and enriched in its heavy isotopes, while another fraction would have escaped from the atmosphere to space, with, or without isotope selection of the lightest isotopes. The combination of these two processes over long periods of time provides thereby a key process for explaining the evolution of its isotopic composition in the atmosphere over time that has been observed in Archean archives (Pujol et al., 2011).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hewins_etal2014,

title = {The Paris meteorite, the least altered CM chondrite so far},

author = {R. H. Hewins and M. Bourot-Denise and B. Zanda and H. Leroux and J. A. Barrat and M. Humayun and C. G\"{o}pel and R. C. Greenwood and I. A. Franchi and S. Pont and J. P. Lorand and C. Courn`ede and J. Gattacceca and P. Rochette and M. Kuga and Y. Marrocchi and B. Marty},

doi = {10.1016/j.gca.2013.09.014},

year  = {2014},

date = {2014-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {124},

pages = {190--222},

abstract = {The Paris chondrite provides an excellent opportunity to study CM chondrules and refractory inclusions in a more pristinestate than currently possible from other CMs, and to investigate the earliest stages of aqueous alteration captured within asingle CM bulk composition. It was found in the effects of a former colonial mining engineer and may have been an observedfall. The texture, mineralogy, petrography, magnetic properties and chemical and isotopic compositions are consistent withclassification as a CM2 chondrite. There are 45 vol.% high-temperature components mainly Type I chondrules (with olivinemostly Fa0--2, mean Fa0.9) with granular textures because of low mesostasis abundances. Type II chondrules contain olivineFa7 to Fa76. These are dominantly of Type IIA, but there are IIAB and IIB chondrules, II(A)B chondrules with minor highlyferroan olivine, and IIA(C) with augite as the only pyroxene. The refractory inclusions in Paris are amoeboid olivine aggregates(AOAs) and fine-grained spinel-rich Ca--Al-rich inclusions (CAIs). The CAI phases formed in the sequence hibonite,perovskite, grossite, spinel, gehlenite, anorthite, diopside/fassaite and forsterite. The most refractory phases are embeddedin spinel, which also occurs as massive nodules. Refractory metal nuggets are found in many CAI and refractory platinumgroup element abundances (PGE) decrease following the observed condensation sequences of their host phases. Mn--Cr isotopemeasurements of mineral separates from Paris define a regression line with a slope of 53Mn/55Mn = (5.76 textpm 0.76)  106.If we interpret Cr isotopic systematics as dating Paris components, particularly the chondrules, the age is 4566.44 textpm 0.66 Myr,which is close to the age of CAI and puts new constraints on the early evolution of the solar system. Eleven individual Parissamples define an O isotope mixing line that passes through CM2 and CO3 falls and indicates that Paris is a very fresh sample,with variation explained by local differences in the extent of alteration. The anhydrous precursor to the CM2s was CO3-like,but the two groups differed in that the CMs accreted a higher proportion of water. Paris has little matrix (47%, plus 8% fine grained rims) and is less altered than other CM chondrites. Chondrule silicates (except mesostasis), CAI phases, submicronforsterite and amorphous silicate in the matrix are all well preserved in the freshest domains, and there is abundant metalpreserved (metal alteration stage 1 of Palmer and Lauretta (2011)). Metal and sulfide compositions and textures correspondto the least heated or equilibrated CM chondrites, Category A of Kimura et al. (2011). The composition of tochilinite--cronstedtiteintergrowths gives a PCP index of 2.9. Cronstedtite is more abundant in the more altered zones whereas in normalhighly altered CM chondrites, with petrologic subtype 2.6--2.0 based on the S/SiO2 and PFeO/SiO2 ratios in PCP or tochilinite--cronstedtite intergrowths (Rubin et al., 2007), cronstedtite is destroyed by alteration. The matrix in fresh zones has CIchondritic volatile element abundances, but interactions between matrix and chondrules occurred during alteration, modifyingthe volatile element abundances in the altered zones. Paris has higher trapped Ne contents, more primitive organic compounds,and more primitive organic material than other CMs. There are gradational contacts between domains of differentdegree of alteration, on the scale of 1 cm, but also highly altered clasts, suggesting mainly a water-limited style of alteration,with no significant metamorphic reheating.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kuga_etal2014,

title = {Nitrogen isotopic fractionation during abiotic synthesis of organic solid particles},

author = {M. Kuga and N. Carrasco and B. Marty and Y. Marrocchi and S. Bernard and T. Rigaudier and B. Fleury and L. Tissandier},

doi = {10.1016/j.epsl.2014.02.037},

year  = {2014},

date = {2014-01-01},

journal = {Earth and Planetary Science Letters},

volume = {393},

pages = {2--13},

abstract = {The formation of organic compounds is generally assumed to result from abiotic processes in the Solar System, with the exception of biogenic organics on Earth. Nitrogen-bearing organics are of particular interest, notably for prebiotic perspectives but also for over all comprehension of organic formation in the young Solar System and in planetary atmospheres. We have investigated abiotic synthesis of organics upon plasma discharge, with special attention to N isotope fractionation. Organic aerosols were synthesized from N2--CH4 and N2--CO gaseous mixtures using low-pressure plasma discharge experiments, aimed at simulating chemistry occurring in Titantextquoteright atmosphere and in the protosolar nebula, respectively. The nitrogen content, the N speciation and the N isotopic composition were analyzed in the resulting organic aerosols. Nitrogen is efficiently incorporated in to the synthesized solids, independently of the oxidation degree, of the N2 content of the starting gas mixture, and of the nitrogen speciation in the aerosols.The aerosols are depleted in 15N by15--25- relative to the initial N2 gas, whatever the experimental setup is. Such an isotopic fractionation is attributed to mass-dependent kinetic effect(s). Nitrogen isotope fractionation upon electric discharge cannot account for the large N isotope variations observed among Solar System objects and reservoirs. Extreme N isotope signatures in the Solar System are more likely the result of self-shielding during N2 photodissociation, exotic effect during photodissociation of N2 and/or low temperature ion-molecule isotope exchange. Kinetic N isotope fractionation may play a significant role in the Titantextquoterights atmosphere. On the Titantextquoterights night side, 15N depletion resulting from electron driven reactions may counterbalance photo-induced 15N enrichments occurring on the daytextquoterights side.We also suggest that the low $delta$15N values of Archaean organic matter (Beaumont and Robert,1999) are partly the result of abiotic synthesis of organics that occurred at that time, and that the subsequent development of the biosphere resulted in shifts of $delta$15N towards higher values.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Michel_etal2014,

title = {MarcoPolo-R: Near-Earth Asteroid sample return mission selected for the assessment study phase of the ESA program cosmic vision},

author = {P. Michel and M. A. Barucci and A. F. Cheng and H. B\"{o}hnhardt and J. R. Brucato and E. Dotto and P. Ehrenfreund and I. A. Franchi and S. F. Green and L. M. Lara and B. Marty and D. Koschny and D. Agnolon},

doi = {10.1016/j.actaastro.2012.05.030},

year  = {2014},

date = {2014-01-01},

journal = {Acta Astronautica},

volume = {93},

abstract = {This paper presents the sample return mission to a primitive Near-Earth Asteroid (NEA) MarcoPolo-R proposed to the European Space Agency in December 2010. MarcoPolo-R was selected in February 2011 with three other missions addressing different science objectives for the two-year Assessment Phase of the Medium-Class mission competition of the Cosmic Vision 2 program for launch in 2022. The baseline target of MarcoPolo-R is the binary NEA (175706) 1996 FG3, which offers an efficient operational and technical mission profile.A binary target also provides enhanced science return. The choice of a binary target allows several scientific investigations to occur more easily than through a single object, in particular regarding the fascinating geology and geophysics of asteroids. MarcoPolo-R will rendezvous with a primitive, organic-rich NEA, scientifically characterize it at multiple scales, and return a bulk sample to Earth for laboratory analyses. The MarcoPolo-R sample will provide arepresentative sample from the surface of a known asteroid with known geologic context, and will contribute to the inventory of primitive material that is probably missing from the meteorite collection.The MarcoPolo-R samples will thus contribute to the exploration of theorigin of planetary materials and initial stages of habitable planet formation, to the identification and characterization of the organics and volatiles in a primitive asteroid and to the understanding of the unique geomorphology, dynamics and evolution of a binary asteroid that belongs to the PotentiallyHazardous Asteroid (PHA) population.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zimmermann+Marty2014,

title = {M\'{e}thodes dtextquoterightextraction des gaz rares sous ultravide},

author = {L. Zimmermann and B. Marty},

year  = {2014},

date = {2014-01-01},

journal = {Techniques de ltextquoterighting\'{e}nieur},

volume = {j6632},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Albarde_etal2013,

title = {Asteroidal impacts and the origin of terrestrial and lunar volatiles},

author = {F. Albar`ede and C. Ballhaus and J. Blichert-Toft and C. T. Lee and B. Marty and F. Moynier and Q. Z. Yin},

doi = {doi.org/10.1016/j.icarus.2012.10.026},

year  = {2013},

date = {2013-01-01},

journal = {Icarus},

volume = {222},

pages = {44--52},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Cartigny+Marty2013,

title = {Nitrogen isotopes and mantle geodynamics: The emergence of life and the atmosphere-- crust--mantle connection},

author = {P. Cartigny and B. Marty},

doi = {10.2113/gselements.9.5.359},

year  = {2013},

date = {2013-01-01},

journal = {Elements},

volume = {9},

pages = {359--366},

abstract = {Nitrogen shows unique features among the volatile elements. To be cycled, atmospheric di-nitrogen (N2) needs to be reduced, which is efficiently done by bacterial processes. Crustal uptake of nitrogen and its eventual recycling into the mantle is thus primarily mediated by the biosphere. There is also a marked isotopic contrast between the mantle (15N depleted) and the Earthtextquoterights surface (15N enriched). Although the cause of such disequilibrium is not fully understood, it provides insights into mantle--surfaceinteractions over geological time, including recycling of surface sediments into the deep mantle.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Colin_etal2013,

title = {Mechanisms of magma degassing at mid-oceanic ridges and the local volatile composition (4He--40Ar n--CO2) of the mantle by laser ablation analysis of individual MORB vesicles},

author = {A. Colin and P. Burnard and B. Marty},

doi = {10.1016/j.epsl.2012.10.022},

year  = {2013},

date = {2013-01-01},

journal = {Earth and Planetary Science Letters},

volume = {361},

pages = {183--194},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{deMoor_etal2013,

title = {Sulfur degassing at Erta Ale (Ethiopia) and Masaya (Nicaragua) volcanoes: Implications for degassing processes and oxygen fugacities of basaltic systems},

author = {J. M. Moor and T. P. Fischer and Z. D. Sharp and P. L. King and M. Wilke and R. E. Botcharnikov and E. Cottrell and M. Zelenski and B. Marty and K. Klimm and C. Rivard and D. Ayalew and C. Ramirez and K. A. Kelley},

doi = {10.1002/ggge.20255},

year  = {2013},

date = {2013-01-01},

journal = {Geochemistry, Geophysics, Geosystems G3},

abstract = {We investigate the relationship between sulfur and oxygen fugacity at Erta Ale and Masaya volcanoes. Oxygen fugacity was assessed utilizing Fe3þ/PFe and major element compositions measured in olivine-hosted melt inclusions and matrix glasses. Erta Ale melts have Fe3þ/PFe of 0.15--0.16, reflecting fO2 of DQFM 0.060.3, which is indistinguishable from fO2 calculated from CO2/CO ratios inhigh-temperature gases. Masaya is more oxidized at DQFM þ1.760.4, typical of arc settings. Sulfur isotope compositions of gases and scoria at Erta Ale (34Sgas0.5%; 34Sscoriaþ0.9%) and Masaya (34Sgasþ4.8%; 34Sscoriaþ7.4%) reflect distinct sulfur sources, as well as isotopic fractionation during degassing (equilibrium and kinetic fractionation effects). Sulfur speciation in melts plays an important role in isotope fractionation during degassing and S6þ/PS is \<0.07 in Erta Ale melt inclusions compared to \>0.67 in Masaya melt inclusions. No change is observed in Fe3þ/PFe or S6þ/PS with extent of S degassing at Erta Ale, indicating negligible effect on fO2, and further suggesting that H2S is the dominantgas species exsolved from the S2-rich melt (i.e., no redistribution of electrons). High SO2/H2S observed in Erta Ale gas emissions is due to gas re-equilibration at low pressure and fixed fO2. Sulfur budget considerations indicate that the majority of S injected into the systems is emitted as gas, which is therefore representative of the magmatic S isotope composition. The composition of the Masaya gas plume (þ4.8%) cannot be explained by fractionation effects but rather reflects recycling of high 34S oxidized sulfur through the subduction zone.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fri_etal2013,

title = {Effects of atmospheric entry heating on the noble gas and nitrogen content of micrometeorites},

author = {E. F\"{u}ri and J. Al\'{e}on and A. Toppani and B. Marty and G. Libourel and L. Zimmermann},

doi = {10.1016/j.epsl.2013.07.031},

year  = {2013},

date = {2013-01-01},

journal = {Earth and Planetary Science Letters},

volume = {377-378},

pages = {1--12},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mabry_etal2013,

title = {High-precision helium isotope measurements in air},

author = {J. Mabry and T. Lan and P. Burnard and B. Marty},

doi = {10.1039/c3ja50155h},

year  = {2013},

date = {2013-01-01},

journal = {Journal of Analytical Atomic Spectrometry},

volume = {28},

pages = {1903},

abstract = {Helium has two natural isotopes which have contrasted, and variable sources and sinks in the atmosphere (3He/4Heair textonequarter 1.382 +- 0.005 x 10-6). Variations in the atmospheric helium isotopic composition may exist below typical measurement precision thresholds (0.2 to 0.5%, 2s). In order to investigate this possibility, it is necessary to be able to consistently measure helium isotopes in air with high precision (below 0.2% 2s). We have created an air purification and measurement system that improves the helium isotope measurement precision. By purifying a large quantity of air at the start of a measurement cycle we canmake rapid standard-bracketed measurements. Controlling the amount of helium in each measured aliquot minimizes pressure effects. With this method we improve the standard errors by 2 x over measuring the same amount of gas in a single step. Individual measurements have standard errors of 0.2 to 0.3% (2s), with three repeat samples needed to reach 0.1% or better errors. The long-term reproducibility of our calibration sample is 0.033% (2s).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marrocchi+Marty2013,

title = {Experimental determination of the xenon isotopic fractionation during adsorption},

author = {Y. Marrocchi and B. Marty},

doi = {10.1002/grl.50845},

year  = {2013},

date = {2013-01-01},

journal = {Geophysical Research Letters},

volume = {40},

pages = {4165--4170},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2013_2,

title = {Nitrogen isotopic composition and density of the Archean atmosphere},

author = {B. Marty and L. Zimmermann and M. Pujol and R. Burgess and P. Philippot},

doi = {10.1126/science.1240971},

year  = {2013},

date = {2013-01-01},

journal = {Sciencexpress},

number = {9},

abstract = {Understanding the atmospheretextquoterights composition during the Archean eon is a fundamental issue to unravel ancient environmental conditions. We show from the analysis of nitrogen and argon isotopes in fluid inclusions trapped in 3.0-3.5 Ga hydrothermal quartz that the PN2 of the Archean atmosphere was lower than 1.1 bar, possibly as low as 0.5 bar, and had a nitrogen isotopic composition comparable to the present-day one. These results imply that dinitrogen did not play a significant role in the thermal budget of the ancient Earth and that the Archean PCO2 was probably lower than 0.7 bar.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pujol_etal2013,

title = {Argon isotopic composition of Archaean atmosphere probes early Earth geodynamics},

author = {M. Pujol and B. Marty and R. Burgess and G. Turner and P. Philippot},

doi = {10.1038/nature12152},

year  = {2013},

date = {2013-01-01},

journal = {Nature},

volume = {498},

number = {6},

pages = {87},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Roskosz_etal2013,

title = {Nitrogen solubility in molten metal and silicate at high pressure and temperature},

author = {M. Roskosz and M. A. Bouhifd and A. P. Jephcoat and B. Marty and B. O. Mysen},

doi = {10.1016/j.gca.2013.07.007},

year  = {2013},

date = {2013-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {121},

pages = {15--28},

abstract = {Nitrogen is the dominant gas in Earth atmosphere, but its behavior during the Earthtextquoteright differentiation is poorly known. To aid in identifying the main reservoirs of nitrogen in the Earth, nitrogen solubility was determined experimentally in a mixture of molten CI-chondrite model composition and (Fe, Ni) metal alloy liquid. Experiments were performed in a laser-heated diamond-anvil cell at pressures to 18 GPa and temperatures to 2850 textpm 200 K. Multi-anvil experiments were also performedat 5 and 10 GPa and 2390 textpm 50 K. The nitrogen content increases with pressure in both metal and silicate reservoirs. It also increases with the iron content of the (Fe, Ni) alloy. Sievertstextquoteright formalism successfully describes the nitrogen solubility in metals up to 18 GPa. Henrytextquoterights law applies to nitrogen-saturated silicate melts up to 4--5 GPa. Independently of these solubility models, it is shown that the partition coefficient of nitrogen between metal and silicate melts changes from almost 10 4 at ambient pressure to about 10--20 for pressures higher than 1 GPa. The pressure-dependence of the nitrogen partitioning can explain the recently suggested depletion of nitrogen relative to other volatiles in the bulk silicate Earth.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Teng_etal2013,

title = {Iron isotopic systematics of oceanic basalts},

author = {F. Z. Teng and N. Dauphas and S. Huang and B. Marty},

doi = {10.1016/j.gca.2012.12.027},

year  = {2013},

date = {2013-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {107},

pages = {12--26},

abstract = {The iron isotopic compositions of 93 well-characterized basalts from geochemically and geologically diverse mid-ocean ridge segments, oceanic islands and back arc basins were measured. Forty-three MORBs have homogeneous Fe isotopic composition, with d 56 Fe ranging from +0.07 \& to +0.14 \& and an average of +0.105 textpm 0.006 \&(2SD/p},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zelenski_etal2013,

title = {Trace elements in the gas emissions from the Erta Ale volcano, Afar, Ethiopia},

author = {M. E. Zelenski and T. P. Fischer and Maarten Moor and B. Marty and L. Zimmermann and D. Ayalew and A. Nekrasov and V. K. Karandashev},

doi = {10.1016/j.chemgeo.2013.08.022},

year  = {2013},

date = {2013-01-01},

journal = {Chemical Geology},

volume = {357},

pages = {95--116},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Barucci_etal2012,

title = {MarcoPolo-R near earth asteroid sample return mission},

author = {M. A. Barucci and A. F. Cheng and P. Michel and L. A. M. Benner and R. P. Binzel and P. A. Bland and H. Bohnhardt and J. R. Brucato and A. C. Bagatin and P. Cerroni and E. Dotto and A. Fitzsimmons and I. A. Franchi and S. F. Green and L. M. Lara and J. Licandro and B. Marty and K. Muinone and A. Nathues and J. Oberst and A. S. Rivkin and F. Robert and R. Saladino and J. M. Trigo-Rodriguez and S. Ulamec and M. Zolensky},

doi = {10.1007/s10686-011-9231-8},

year  = {2012},

date = {2012-01-01},

journal = {Experimental Astronomy},

volume = {33},

number = {2-3},

pages = {645--684},

abstract = {MarcoPolo-R is a sample return mission to a primitive Near-Earth Asteroid (NEA) proposed in collaboration with NASA. It will rendezvous with a primitive NEA, scientifically characterize it at multiple scales, and return a unique sample to Earth unaltered by the atmospheric entry process or terrestrial weathering. MarcoPolo-R will return bulk samples (up to 2 kg) from an organic-rich binary asteroid to Earth for laboratory analyses, allowing us to: explore the origin of planetary materials and initial stages of habitable planet formation; identify and characterize the organics and volatiles in a primitive asteroid; understand the unique geomorphology, dynamics and evolution of a binary NEA. This project is based on the previous Marco Polo mission study, which was selected for the Assessment Phase of the first round of Cosmic Vision. Its scientific rationale was highly ranked by ESA committees and it was not selected only because the estimated cost was higher than the allotted amount for an M class mission. The cost of MarcoPolo-R will be reduced to within the ESA medium mission budget by collaboration with APL (John Hopkins University) and JPL in the NASA program for coordination with ESAtextquoterights Cosmic Vision Call. The baseline target is a binary asteroid (175706) 1996 FG3, which offers a very efficient operational and technical mission profile. A binary target also provides enhanced science return. The choice of this target will allow new investigations to be performed more easily than at a single object, and also enables investigations of the fascinating geology and geophysics of asteroids that are impossible at a single object. Several launch windows have been identified in the time-span 2020-2024. A number of other possible primitive single targets of high scientific interest have been identified covering a wide range of possible launch dates. The baseline mission scenario of MarcoPolo-R to 1996 FG3 is as follows: a single primary spacecraft provided by ESA, carrying the Earth Re-entry Capsule, sample acquisition and transfer system provided by NASA, will be launched by a Soyuz-Fregat rocket from Kourou into GTO and using two space segment stages. Two similar missions with two launch windows, in 2021 and 2022 and for both sample return in 2029 (with mission duration of 7 and 8 years), have been defined. Earlier or later launches, in 2020 or 2024, also offer good opportunities. All manoeuvres are carried out by a chemical propulsion system. MarcoPolo-R takes advantage of three industrial studies completed as part of the previous Marco Polo mission (see ESA/SRE (2009)3, Marco Polo Yellow Book) and of the expertise of the consortium led by Dr. A.F. Cheng (PI of the NASA NEAR Shoemaker mission) of the JHU-APL, including JPL, NASA ARC, NASA LaRC, and MIT.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Chassefire_etal2012,

title = {The evolution of Venus: Present state of knowledge and future exploration},

author = {E. Chassefi`ere and R. Wieler and B. Marty and F. Leblanc},

doi = {10.1016/j.pss.2011.04.007},

year  = {2012},

date = {2012-01-01},

journal = {Planetary and Space Science},

volume = {63-64},

pages = {15--23},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{ChennaouiAoudjehane_etal2012,

title = {Tissint Martian Meteorite},

author = {H. Chennaoui Aoudjehane and G. Avice and J. A. Barrat and O. Boudouma and G. Chen and M. J. M. Duke and I. A. Franchi and J. Gattacceca and M. M. Grady and R. C. Greenwood and C. D. K. Herd and R. Hewins and A. Jambon and B. Marty and P. Rochette and C. L. Smith and V. Sautter and A. Verchovsky and P. Weber and B. Zanda},

doi = {10.1126/science.1224514},

year  = {2012},

date = {2012-01-01},

journal = {SciencExpress},

number = {octobre},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fri_etal2012,

title = {Constraints on the flux of meteoritic and cometary water on the Moon from volatile element (N--Ar) analyses of single lunar soil grains, Luna 24 core},

author = {E. F\"{u}ri and B. Marty and S. S. Assonov},

doi = {10.1016/j.icarus.2011.11.037},

year  = {2012},

date = {2012-01-01},

journal = {Icarus},

volume = {218},

number = {1},

pages = {220--229},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty2012,

title = {The origins and concentrations of water, carbon, nitrogen and noble gas on Earth},

author = {B. Marty},

doi = {10.1016/j.epsl.2011.10.040},

year  = {2012},

date = {2012-01-01},

journal = {Earth and Planetary Science Letters},

volume = {313-314},

pages = {56--66},

abstract = {The isotopic compositions of terrestrial hydrogen and nitrogen are clearly different from those of the nebular gas from which the solar system formed, and also differ from most of cometary values. Terrestrial N and H isotopic compositions are in the range of values characterizing primitive meteorites, which suggests that water, nitrogen, and other volatile elements on Earth originated from a cosmochemical reservoir that also sourced the parent bodies of primitive meteorites. Remnants of the proto-solar nebula (PSN) are still present in the mantle, presumably signing the sequestration of PSN gas at an early stage of planetary growth. The contribution of cometary volatiles appears limited to a few percents at most of the total volatile inventory of the Earth. The isotope signatures of H, N, Ne and Ar can be explained by mixing between two endmembers of solar and chondritic compositions, respectively, and do not require isotopic fractionation during hydrodynamic escape of an early atmosphere. The terrestrial inventory of 40Ar (produced by the decay of 40K throughout the Earthtextquoterights history) suggests that a significant fraction of radiogenic argonmay be still trapped in the silicate Earth. By normalizing other volatile element abundances to this isotope, it is proposed that the Earth is not as volatile-poor as previously thought. Our planet may indeed contain up to 3000 ppm water (preferred range : 1000--3000 ppm), and up to 500 ppm C, both largely sequestrated in the solid Earth. This volatile content is equivalent to an 2 (textpm1) % contribution of carbonaceous chondrite (CI-CM)material to a dry proto-Earth,which is higher than the contribution of chondritic material advocated to account for the platinum group element budget of the mantle. Such a (relatively) high contribution of volatile-rich matter is consistent with the accretion of a few wet planetesimals during Earth accretion, as proposed by recent dynamical models. The abundance pattern ofmajor volatile elements and of noble gases is also chondritic, with two notable exceptions. Nitrogen is depleted by one order of magnitude relative to water, carbon and most noble gases, which is consistent with either N retention in a mantle phase during magma generation, or trapping of N in the core. Xenon is also depleted by one order of magnitude, and enriched in heavy isotopes relative to chondritic or solar Xe (the so-called textquotelefttextquoteleftxenon paradoxtextquoterighttextquoteright). This depletion and isotope fractionation might have taken place due to preferential ionization of xenon by UV light fromthe early Sun, either before Earthtextquoterights formation on parent material, or during irradiation of the ancient atmosphere. The second possibility is consistent with a recent report of chondritic-like Xe in Archean sedimentary rocks that suggests that this process was still ongoing during the Archean eon (Pujol et al., 2011). If the depletion of Xe in the atmosphere was a long-term process that took place after the Earth-building events, then the amounts of atmospheric 129Xe and 131--136Xe, produced by the short-lived radioactivities of 129I (T1/2=16Ma) and 244Pu (T1/2=82Ma), respectively, need to be corrected for subsequent loss. Doing so, the I--Pu--Xe age of the Earth becomes ≤50 Ma after start of solar system formation, instead of 120 Ma as computed with the present-day atmospheric Xe inventory.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wilson_etal2012,

title = {The 2010 European Venus Explorer (EVE) mission proposal},

author = {C. F. Wilson and A. Chassagne and E. Hinglais and K. H. Baines and T. S. Ballint and J. J. Berthelier and J. Blamont and G. Durry and C. S. Ferenez and R. E. Grimm and T. Imamura and J. L. Josset and F. Leblanc and S. Lebonnois and J. J. Leitner and S. S. Limaye and B. Marty and E. Palomba and S. Pogrebenko and S. C. R. Rafkin and D. L. Tallboys and R. Wieler and L. V. Zasova and C. Szopa and team},

doi = {10.1007/s10686-011-9259-9},

year  = {2012},

date = {2012-01-01},

journal = {Experimental Astronomy},

volume = {33},

pages = {305--335},

abstract = {The European Venus Explorer (EVE) mission described in this paper was proposed in December 2010 to ESA as an textquoteleftM-classtextquoteright mission under the Cosmic Vision programme. It consists of a single balloon platform floating in the middle of the main convective cloud layer of Venus at an altitude of 55 km, where temperatures and pressures are benign (�`u25◦C and �`u0.5 bar). The balloon float lifetime would be at least 10 Earth days, long enough to guarantee at least one full circumnavigation of the planet. This offers an ideal platform for the two main science goals of the mission: study of the current climate through detailed characterization of cloud-level atmosphere, and investigation of the formation and evolution of Venus, through careful measurement of noble gas isotopic abundances. These investigations would provide key data for comparative planetology of terrestrial planets in our solar system and beyond.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Srama_etal2012,

title = {SARIM PLUS-sample return of comet 67P/CG and of interstellar matter},

author = {R. Srama and H. Kruger and T. Yamaguchi and T. Stephan and M. Burchell and A. T. Kearsley and V. Sterken and F. Postberg and S. Kempf and E. Grun and N. Altobelli and P. Ehrenfreund and V. Dikarev and M. Horanyi and Z. Sternovsky and J. D. Carpenter and A. Westphal and Z. Gainsforth and A. Krabbe and J. Agarwal and H. Yano and J. Blum and H. Henkel and J. Hiller and P. Hoppe and M. Trieloff and S. Hsu and A. Mocker and K. Fiege and S. F. Green and A. Bischoff and F. Esposito and R. Laufer and T. W. Hyde and G. Herdrich and S. Fasoulas and A. Jackel and G. Jones and P. Jenniskens and E. Khalisi and G. Moragas-Klostermeyer and F. Spahn and H. U. Keller and P. Frisch and A. C. Levasseur-Regourd and N. Pailer and K. Altwegg and C. Engrand and S. Auer and J. Silen and S. Sasaki and M. Kobayashi and J. Schmidt and J. Kissel and B. Marty},

doi = {10.1007/s10686-011-9285-7},

year  = {2012},

date = {2012-01-01},

urldate = {2012-01-01},

journal = {Experimental Astronomy},

volume = {33},

number = {2-3},

pages = {723--751},

abstract = {The Stardust mission returned cometary, interplanetary and (probably) interstellar dust in 2006 to Earth that have been analysed in Earth laboratories worldwide. Results of this mission have changed our view and knowledge on the early solar nebula. The Rosetta mission is on its way to land on comet 67P/Churyumov-Gerasimenko and will investigate for the first time in great detail the comet nucleus and its environment starting in 2014. Additional astronomy and planetary space missions will further contribute to our understanding of dust generation, evolution and destruction in interstellar and interplanetary space and provide constraints on solar system formation and processes that led to the origin of life on Earth. One of these missions, SARIM-PLUS, will provide a unique perspective by measuring interplanetary and interstellar dust with high accuracy and sensitivity in our inner solar system between 1 and 2 AU. SARIM-PLUS employs latest in-situ techniques for a full characterisation of individual micrometeoroids (flux, mass, charge, trajectory, composition()) and collects and returns these samples to Earth for a detailed analysis. The opportunity to visit again the target comet of the Rosetta mission 67P/Churyumov-Gerasimeenternko, and to investigate its dusty environment six years after Rosetta with complementary methods is unique and strongly enhances and supports the scientific exploration of this target and the entire Rosetta mission. Launch opportunities are in 2020 with a backup window starting early 2026. The comet encounter occurs in September 2021 and the reentry takes place in early 2024. An encounter speed of 6 km/s ensures comparable results to the Stardust mission.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marrocchi_etal2011,

title = {Adsorption of xenon ions onto defects in organic surfaces: Implications for the origin and the nature of organics in primitive meteorites},

author = {Y. Marrocchi and B. Marty and P. Reinhardt and F. Robert},

doi = {10.1016/j.gca.2011.07.048},

year  = {2011},

date = {2011-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {75},

pages = {6255--6266},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2011,

title = {A 15N-Poor Isotopic Composition for the Solar System As Shown by Genesis Solar Wind Samples},

author = {B. Marty and M. Chaussidon and R. G. Wiens and A. Jurewicz and D. L. Burnett},

year  = {2011},

date = {2011-01-01},

journal = {Science},

volume = {332},

number = {6037},

pages = {1533--1536},

abstract = {The Genesis mission sampled solar wind ions to document the elemental and isotopic compositions of the Sun and, by inference, of the protosolar nebula. Nitrogen was a key target element because the extent and origin of its isotopic variations in solar system materials remain unknown. Isotopic analysis of a Genesis Solar Wind Concentrator target material shows that implanted solar wind nitrogen has a 15N/14N ratio of 2.18 textpm 0.02 texttimes 10−3 (that is, ≈40% poorer in 15N relative to terrestrial atmosphere). The 15N/14N ratio of the protosolar nebula was 2.27 textpm 0.03 texttimes 10−3, which is the lowest 15N/14N ratio known for solar system objects. This result demonstrates the extreme nitrogen isotopic heterogeneity of the nascent solar system and accounts for the 15N-depleted components observed in solar system reservoirs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pujol_etal2011,

title = {Chondritic-like xenon trapped in Archean rocks: A possible signature of the ancient atmosphere},

author = {M. Pujol and B. Marty and R. Burgess},

doi = {10.1016/j.epsl.2011.05.053},

year  = {2011},

date = {2011-01-01},

journal = {Earth and Planetary Science Letters},

volume = {308},

number = {3-4},

pages = {298--306},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2010,

title = {Chronology and shock history of the Bencubbin meteorite: A nitrogen, noble gas, and Ar-Ar investigation of silicates, metal and fluid inclusions},

author = {B. Marty and S. Kelley and G. Turner},

doi = {10.1016/j.gca.2010.05.035},

year  = {2010},

date = {2010-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {74},

pages = {6636--6653},

abstract = {We have investigated the distribution and isotopic composition of nitrogen and noble gases, and the Ar--Ar chronology of the Bencubbin meteorite. Gases were extracted from different lithologies by both stepwise heating and vacuum crushing. Significant amounts of gases were found to be trapped within vesicles present in silicate clasts. Results indicate a global redistribution of volatile elements during a shock event caused by an impactor that collided with a planetary regolith. A transient atmosphere was created that interacted with partially or totally melted silicates and metal clasts. This atmosphere contained 15N-rich nitrogen with a pressure P3 105 hPa, noble gases, and probably, although not analyzed here, other volatile species. Nitrogen and noble gases were re-distributed among bubbles, metal, and partly or totally melted silicates, according to their partition coefficients among these different phases. The occurrence of N2 trapped in vesicles and dissolved in silicates indicates that the oxygen fugacity (fO2) was greater than the iron--wutextasciidieresis stite buffer during the shock event. Ar--Ar dating of Bencubbin glass gives an age of 4.20 textpm 0.05 Ga, which probably dates this impact event. The cosmic-ray exposure age is estimated at 40 Ma with two different methods. Noble gases present isotopic signatures similar to those of textquotelefttextquoteleftphase Qtextquoterighttextquoteright (the major host of noble gases trapped in chondrites) but elemental patterns enriched in light noble gases (He, Ne and Ar) relative to Kr and Xe, normalized to the phase Q composition. Nitrogen isotopic data together with 40Ar/36Ar ratios indicate mixing between a 15N-rich component (d15N = +1000\&), terrestrial N, and an isotopically normal, chondritic N.Bencubbin and related 15N-rich meteorites of the CR clan do not show stable isotope (H and C) anomalies, precluding contribution of a nucleosynthetic component as the source of 15N enrichments. This leaves two possibilities, trapping of an ancient, highly fractionated atmosphere, or degassing of a primitive, isotopically unequilibrated, nitrogen component.Although the first possibility cannot be excluded, we favor the contribution of primitive material in the light of the recent finding of extremely 15N-rich anhydrous clasts in the CB/CH Isheyevo meteorite. This unequilibrated material, probably carried by the impactor, could have been insoluble organic matter extremely rich in 15N and hosting isotopically Q-like noble gases, possibly from the outer solar system.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2010_2,

title = {Nitrogen isotopes in the recent solar wind from the analysis of Genesis targets: Evidence for large scale isotope heterogeneity in the early solar system},

author = {B. Marty and L. Zimmermann and P. Burnard and R. Wieler and V. S. Heber and D. L. Burnett and R. G. Wiens and P. Bochsler},

doi = {10.1016/j.gca.2009.09.007},

year  = {2010},

date = {2010-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {74},

pages = {340--355},

abstract = {We have analyzed nitrogen, neon and argon abundances and isotopic ratios in target material exposed in space for 27 months to solar wind (SW) irradiation during the Genesis mission. SW ions were extracted by sequential UV (193 nm) laser ablation of gold-plated material, purified separately in a dedicated line, and analyzed by gas source static mass spectrometry. We analyzed gold-covered stainless steel pieces from the Concentrator, a device that concentrated SW ions by a factor of up to 50. Despite extensive terrestrial N contamination, we could identify a non-terrestrial, N-15-depleted nitrogen end-member that points to a 40% depletion of 15 N in solar-wind N relative to inner planets and meteorites, and define a composition for the present-day Sun (N-15/N-14 = [2.26 +/- 0.67] X 10(-3) 2 sigma), which is indistinguishable from that of Jupitertextquoterights atmosphere. These results indicate that the isotopic composition of nitrogen in the outer convective zone of the Sun has not changed through time, and is representative of the protosolar nebula. Large N-15 enrichments due to e.g., irradiation, low temperature isotopic exchange, or contributions from N-15-rich presolar components, are therefore required to account for inner planet values},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Teng_etal2010,

title = {Magnesium isotopic composition of the Earth and chondrites},

author = {F. Z. Teng and W. Y. Li and S. Ke and B. Marty and N. Dauphas and S. C. Huang and F. Y. Wu and A. Pourmand},

doi = {10.1016/j.gca.2010.04.019},

year  = {2010},

date = {2010-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {74},

number = {14},

pages = {4150--4166},

abstract = {AbstractTo constrain further the Mg isotopic composition of the Earth and chondrites, and investigate the behavior of Mg isotopes during planetary formation and magmatic processes, we report high-precision (textpm0.06\& on d25Mg and textpm0.07\& on d26Mg,2SD) analyses of Mg isotopes for (1) 47 mid-ocean ridge basalts covering global major ridge segments and spanning a broad range in latitudes, geochemical and radiogenic isotopic compositions; (2) 63 ocean island basalts from Hawaii(Kilauea, Koolau and Loihi) and French Polynesia (Society Island and Cook-Austral chain); (3) 29 peridotite xenoliths from Australia, China, France, Tanzania and USA; and (4) 38 carbonaceous, ordinary and enstatite chondrites including 9 chondrite groups (CI, CM, CO, CV, L, LL, H, EH and EL). Oceanic basalts and peridotite xenoliths have similar Mg isotopic compositions, with average values of d25Mg = 0.13 textpm 0.05 (2SD) and d26Mg = 0.26 textpm 0.07 (2SD) for global oceanic basalts (n = 110) and d25Mg = 0.13 textpm 0.03 (2SD) and d26Mg = 0.25 textpm 0.04 (2SD) for global peridotite xenoliths (n = 29). The identical Mg isotopic compositions in oceanic basalts and peridotites suggest that equilibrium Mg isotope fractionation during partial melting of peridotite mantle and magmatic differentiation of basaltic magma is negligible. Thirty-eight chondrites have indistinguishable Mg isotopic compositions, with d25Mg = 0.15 textpm 0.04 (2SD) and d26Mg = 0.28 textpm 0.06 (2SD). The constancy of Mg isotopic compositions in all major types of chondrites suggest that primary and secondary processes that affected the chemical and oxygen isotopic compositions of chondrites did not significantly fractionate Mg isotopes.Collectively, the Mg isotopic composition of the Earthtextquoterights mantle, based on oceanic basalts and peridotites, is estimated to be 0.13 textpm 0.04 for d25Mg and 0.25 textpm 0.07 for d26Mg (2S},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Chassefire_etal2009,

title = {European Venus Explorer (EVE): an in-situ mission to Venus},

author = {E. Chassefi`ere and O. Korablev and T. Imamura and K. H. Baines and C. F. Wilson and D. V. Titov and K. L. Aplin and T. Balint and J. E. Blamont and C. G. Cochrane and C. Ferencz and F. Ferri and M. Gerasimov and J. J. Leitner and J. Lopez-Moreno and B. Marty and et al},

doi = {10.1007/s10686-008-9093-x},

year  = {2009},

date = {2009-01-01},

journal = {Experimental Astronomy},

volume = {23},

number = {3},

pages = {741--760},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Coltice_etal2009,

title = {Xenon isotope constraints on the thermal evolution of the early Earth},

author = {N. Coltice and B. Marty and R. Yokochi},

doi = {10.1016/j.chemgeo.2009.04.017},

year  = {2009},

date = {2009-01-01},

journal = {Chemical Geology},

volume = {266},

number = {1-2},

pages = {4--9},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Coustenis_etal2009,

title = {TandEM: Titan and Enceladus mission},

author = {A. Coustenis and S. K. Atreya and T. Balint and R. H. Brown and M. K. Dougherty and F. Ferri and M. Fulchignoni and D. Gautier and R. A. Gowen and C. A. Griffith and L. I. Gurvits and R. Jaumann and Y. Langevin and M. R. Leese and J. I. Lunine and C. P. McKay and X. Moussas and I. M\"{u}ller-Wodarg and F. Neubauer and T. C. Owen and F. Raulin and E. C. Sittler and F. Sohl and C. Sotin and G. Tobie and T. Tokano and E. P. Turtle and J. E. Wahlund and J. H. Waite and K. H. Baines and J. Blamont and A. J. Coates and I. Dandouras and T. Krimigis and E. Lellouch and R. D. Lorenz and A. Morse and C. C. Porco and M. Hirtzig and J. Saur and T. Spilker and J. C. Zarnecki and E. Choi and N. Achilleos and R. Amils and P. Annan and D. H. Atkinson and Y. B\'{e}nilan and i. C. Bertucc and B. B\'{e}zard and G. L. Bjoraker and M. Blanc and L. Boireau and J. Bouman and M. Cabane and M. T. Capria and E. Chassefi`ere and P. Coll and M. Combes and J. F. Cooper and A. Coradini and F. Crary and T. Cravens and I. Daglis and E. A. de Angelis and C. Bergh and I. Pater and C. Dunford and G. Durry and O. Dutuit and D. Fairbrother and F. M. Flasar and A. D. Fortes and R. Frampton and M. Fujimoto and M. Galand and O. Grasset and M. Grott and T. Haltigin and A. Herique and F. Hersant and H. Hussmann and Ip W. and Johnson R. and E. Kallio and S. Kempf and M. Knapmeyer and W. Kofman and R. Koop and T. Kostiuk and N. Krupp and M. K\"{u}ppers and H. Lammer and L. -M. Lara and P. Lavvas and S. Le Mou\'{e}lic and S. Lebonnois and S. Ledvina and J. Li and T. A. Livengood and R. M. Lopes and J. -J. Lopez-Moreno and D. Luz and P. R. Mahaffy and U. Mall and J. Martinez-Frias and B. Marty and T. McCord and C. Menor Salvan and A. Milillo and D. G. Mitchell and R. Modolo and O. Mousis and M. Nakamura and C. D. Neish and C. A. Nixon and D. Nna Mvondo and G. Orton and M. Paetzold and J. Pitman and S. Pogrebenko and W. Pollard and O. Prieto-Ballesteros and P. Rannou and K. Reh and L. Richter and F. T. Robb and R. Rodrigo and S. Rodriguez and P. Romani and M. and Ruiz Bermejo},

doi = {10.1007/s10686-008-9103-z},

year  = {2009},

date = {2009-01-01},

journal = {Experimental Astronomy},

volume = {23},

number = {3},

pages = {893--946},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fischer_etal2009,

title = {Upper-mantle volatile chemistry at Oldoinyo Lengai volcano and the origin of carbonatites},

author = {T. P. Fischer and P. Burnard and B. Marty and D. R. Hilton and E. F\"{u}ri and F. Palhol and Z. D. Sharp and F. Mangasini},

doi = {10.1038/nature07977},

year  = {2009},

date = {2009-01-01},

journal = {Nature},

volume = {459},

number = {7243},

pages = {77--80},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marrocchi_etal2009,

title = {Neon isotopic measurements using high-resolution, multicollector noble gas mass spectrometer: HELIX-MC},

author = {Y. Marrocchi and P. Burnard and D. Hamilton and A. Colin and M. Pujol and L. Zimmermann and B. Marty},

doi = {10.1029/2008GC002339},

year  = {2009},

date = {2009-01-01},

journal = {Geochemistry, Geophysics, Geosystems G3},

volume = {10},

number = {4},

pages = {1--8},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2009,

title = {Kronos: exploring the depths of Saturn with probes and remote sensing through an international mission},

author = {B. Marty and T. Guillot and A. Coustenis and et al},

doi = {10.1007/s10686-008-9094-9},

year  = {2009},

date = {2009-01-01},

journal = {Experimental Astronomy},

volume = {23},

number = {3},

pages = {947--976},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pik+Marty2009,

title = {Helium isotopic signature of modern and fossil fluids associated with the Corinth rift fault zone (Greece): Implication for fault connectivity in the lower crust},

author = {R. Pik and B. Marty},

doi = {10.1016/j.chemgeo.2008.09.024},

year  = {2009},

date = {2009-01-01},

journal = {Chemical Geology},

volume = {266},

number = {1-2},

pages = {67--75},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pujol_etal2009,

title = {Xenon in Archean barite: Weak decay of 130Ba, mass-dependent isotopic fractionation and implication for barite formation},

author = {M. Pujol and B. Marty and P. Burnard and P. Philippot},

doi = {10.1016/j.gca.2009.08.002},

year  = {2009},

date = {2009-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {73},

number = {22},

pages = {6834--6846},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Yang_etal2009,

title = {Geochemical applications of noble gases},

author = {T. F. Yang and B. Marty and D. R. Hilton and M. D. Kurz},

doi = {10.1016/j.chemgeo.2009.07.005},

year  = {2009},

date = {2009-01-01},

journal = {Chemical Geology},

volume = {266},

number = {1-2},

pages = {1--3},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Yokochi_etal2009,

title = {Nitrogen in peridotite xenoliths: Lithophile behavior and magmatic isotope fractionation},

author = {R. Yokochi and B. Marty and G. Chazot and P. Burnard},

doi = {10.1016/j.gca.2009.05.054},

year  = {2009},

date = {2009-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {73},

pages = {4843--4861},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zimmermann_etal2009,

title = {Laser Ablation (193 nm), Purification and Determination of Very Low Concentrations of Solar Wind Nitrogen Implanted in Targets from the GENESIS Spacecraft},

author = {L. Zimmermann and P. Burnard and B. Marty and F. Gaboriaud},

doi = {10.1111/j.1751-908X.2009.00021.x},

year  = {2009},

date = {2009-01-01},

journal = {Geostandards and Geoanalytical Research},

volume = {33},

number = {2},

pages = {183--194},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Baruch_etal2008,

title = {Ltextquoterightatmosph`ere en 8 questions},

author = {J. O. Baruch and S. Planton and B. Marty},

year  = {2008},

date = {2008-01-01},

journal = {Les dossiers de la recherche. Le d\'{e}fi climatique. Bac to Basics},

number = {31},

pages = {11--14},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty2008,

title = {Leftovers from core formation},

author = {B. Marty},

doi = {10.1038/ngeo193},

year  = {2008},

date = {2008-01-01},

journal = {Nature Geoscience},

volume = {1},

number = {5},

pages = {290--291},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2008,

title = {Helium and neon abundances and compositions in cometary matter},

author = {B. Marty and R. Palma and R. O. Pepin and L. Zimmermann and D. Schlutter and P. Burnard and A. Westphal and C. J. Snead and S. Bajt and R. H. Becker and J. E. Simones},

doi = {10.1126/science.1148001},

year  = {2008},

date = {2008-01-01},

journal = {Science},

volume = {319},

number = {5859},

pages = {75--78},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pik_etal2008,

title = {Timing of East African Rift development in southern Ethiopia: Implication for mantle plume activity and evolution of topography},

author = {R. Pik and B. Marty and J. Carignan and G. Yirgu and T. Ayalew},

doi = {10.1130/G24233A.1},

year  = {2008},

date = {2008-01-01},

journal = {Geology},

volume = {36},

number = {2},

pages = {167--170},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty+Meibom2007,

title = {Noble gas signature of the Late heavy Bombardment in the Earthtextquoterights atmosphere},

author = {B. Marty and A. Meibom},

year  = {2007},

date = {2007-01-01},

journal = {eEarth},

volume = {2},

pages = {43--49},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Montagner_etal2007,

title = {Mantle upwellings and convective instabilities revealed by seismic tomography and helium isotope geochemistry beneath eastern Africa},

author = {J. P. Montagner and B. Marty and E. Stutzmann and D. Sicilia and M. Cara and R. Pik and J. J. L\'{e}v^eque and G. Roult and E. Beucler and E. Debayle},

doi = {10.1029/2007GL031098},

year  = {2007},

date = {2007-01-01},

journal = {Geophysical Research Letters},

volume = {34},

pages = {L21303},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{VanZuilen_etal2007,

title = {Carbonaceous cherts of the Barberton Greenstone Belt, South Africa: Isotopic, chemical and structural characteristics of individual microstructures},

author = {M. Van Zuilen and M. Chaussidon and C. Rollion-Bard and B. Marty},

doi = {10.1016/j.gca.2006.09.029},

year  = {2007},

date = {2007-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {71},

number = {3},

pages = {655--669},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Chaussidon+Marty2006,

title = {Le Soleil `a fleur de Lune},

author = {M. Chaussidon and B. Marty},

year  = {2006},

date = {2006-01-01},

journal = {La Recherche},

volume = {396},

pages = {58--61},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty2006,

title = {The primordial Porridge},

author = {B. Marty},

doi = {10.1126/science.1125967},

year  = {2006},

date = {2006-01-01},

journal = {Science},

volume = {312},

pages = {706--707},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2006,

title = {Noble gases in the Martian meteorite Northwest Africa 2737: a new chassignite signature},

author = {B. Marty and V. S. Heber and A. Grimberg and R. Wieler and J. A. Barrat},

year  = {2006},

date = {2006-01-01},

journal = {Meteoritics \& Planetary Science},

volume = {41},

number = {5},

pages = {739--748},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{McKeegan_etal2006,

title = {Isotopic compositions of cometary matter returned by Stardust},

author = {K. D. McKeegan and J. Aleon and J. Bradley and D. Brownlee and H. Busemann and A. Butterworth and M. Chaussidon and S. Fallon and C. Floss and J. Gilmour and M. Gounelle and G. Graham and Y. B. Guan and P. R. Heck and P. Hoppe and I. D. Hutcheon and J. Huth and H. Ishii and M. Ito and S. B. Jacobsen and A. Kearsley and L. A. Leshin and M. C. Liu and I. Lyon and K. Marhas and B. Marty and G. Matrajt and A. Meibom and S. Messenger and S. Mostefaoui and S. Mukhopadhyay and K. Nakamura-Messenger and L. Nittler and R. Palma and R. O. Pepin and D. A. Papanastassiou and F. Robert and D. Schlutter and C. J. Snead and F. J. Stadermann and R. Stroud and P. Tsou and A. Westphal and E. D. Young and K. Ziegler and L. Zimmermann and E. Zinner},

doi = {10.1126/science.1135992},

year  = {2006},

date = {2006-01-01},

journal = {Science},

volume = {314},

number = {5806},

pages = {1724--1728},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Montmerle_etal2006,

title = {Solar System formation and early evolution: the first 100 million years},

author = {T. Montmerle and J. C. Augereau and M. Chaussidon and M. Gounelle and B. Marty and A. Morbidelli},

doi = {10.1007/s11038-006-9087-5},

year  = {2006},

date = {2006-01-01},

journal = {Earth, Moon, and Planets},

volume = {98},

number = {1-4},

pages = {39--95},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pik_etal2006,

title = {How many mantle plumes in Africa?: The geochemical point of view},

author = {R. Pik and B. Marty and D. R. Hilton},

doi = {10.1016/j.chemgeo.2005.09.016},

year  = {2006},

date = {2006-01-01},

journal = {Chemical Geology},

volume = {226},

pages = {100--114},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Yokochi+Marty2006,

title = {Fast chemical and isotopic exchange of nitrogen during reaction with hot molybdenum},

author = {R. Yokochi and B. Marty},

year  = {2006},

date = {2006-01-01},

journal = {Geochemistry Geophysics Geosystems G3},

volume = {7},

pages = {Q07004},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ayalew_etal2005,

title = {Sub-lithospheric source for Quaternary alkaline Tepi shield, southwest Ethiopia},

author = {D. Ayalew and B. Marty and P. Barbey and G. Yirgu and E. Ketefo},

year  = {2005},

date = {2005-01-01},

journal = {Geochemical Journal},

volume = {39},

pages = {1--10},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ballentine_etal2005,

title = {Neon isotopes constrain convection and volatile origin in the Earthtextquoterights mantle},

author = {C. J. Ballentine and B. Marty and B. Sherwood Lollar and M. Cassidy},

doi = {10.1038/nature03182},

year  = {2005},

date = {2005-01-01},

journal = {Nature},

volume = {433},

number = {7021},

pages = {33--38},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Fischer+Marty2005,

title = {Volatile abundances in the sub-arc mantle: insights from volcanic and hydrothermal gas discharges},

author = {T. P. Fischer and B. Marty},

doi = {10.1016/j.jvolgeores.2004.07.022},

year  = {2005},

date = {2005-01-01},

journal = {Journal of Volcanology and Geothermal Research},

volume = {104},

pages = {205--216},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gillet_etal2005,

title = {Petrology, geochemistry and cosmic-ray exposure age of lherzolitic shergottite Northwest Africa 1950},

author = {P. Gillet and J. A. Barrat and P. Beck and B. Marty and R. C. Greenwood and I. A. Franchi and M. Bohn and J. Cotten},

year  = {2005},

date = {2005-01-01},

journal = {Meteoritics \& Planetary Science},

volume = {40},

number = {8},

pages = {1175--1184},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marrocchi_etal2005,

title = {Interlayer trapping of noble gases in insoluble organic matter of primitive meteorites},

author = {Y. Marrocchi and S. Derenne and B. Marty and F. Robert},

doi = {10.1016/j.epsl.2005.04.010},

year  = {2005},

date = {2005-01-01},

journal = {Earth and Planetary Science Letters},

volume = {236},

number = {3-4},

pages = {569--578},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marrocchi_etal2005_2,

title = {Low-pressure adsorption of Ar, Kr, and Xe on carbonaceous materials (kerogen and carbon blacks), ferrihydrite, and montmorillonite: Implications for the trapping of noble gases onto meteoritic matter},

author = {Y. Marrocchi and A. Razafitianmaharavo and L. J. Michot and B. Marty},

doi = {10.1016/j.gca.2004.09.016},

year  = {2005},

date = {2005-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {69},

number = {9},

pages = {2419--2430},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty2005,

title = {On the Moon as it was on Earth},

author = {B. Marty},

doi = {10.1038/436631a},

year  = {2005},

date = {2005-01-01},

journal = {Nature},

volume = {436},

number = {7051},

pages = {631--632},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2005,

title = {Nitrogen and noble gases in micrometeorites},

author = {B. Marty and P. Robert and L. Zimmermann},

year  = {2005},

date = {2005-01-01},

journal = {Meteoritics \& Planetary Science},

volume = {40},

number = {6},

pages = {881--894},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Papineau_etal2005,

title = {Nitrogen isotopic composition of ammoniated phyllosilicates: case studies from Precambrian metamorphosed sedimentary rocks},

author = {D. Papineau and S. J. Mojzsis and J. A. Karhu and B. Marty},

doi = {10.1016/j.chemgeo.2004.10.009},

year  = {2005},

date = {2005-01-01},

journal = {Chemical Geology},

volume = {216},

number = {1-2},

pages = {37--58},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Yokochi+Marty2005,

title = {Geochemical constraints on mantle dynamics in the Hadean},

author = {R. Yokochi and B. Marty},

doi = {10.1016/j.epsl.2005.07.020},

year  = {2005},

date = {2005-01-01},

journal = {Earth and Planetary Science Letters},

volume = {238},

number = {1-2},

pages = {17--30},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Yokochi_etal2005,

title = {High 3He/4He ratios in peridotite xenoliths from SW Japan revisited: evidence for cosmogenic 3He released by vacuum crushing},

author = {R. Yokochi and B. Marty and R. Pik and P. Burnard},

doi = {10.1029/2004GC000836},

year  = {2005},

date = {2005-01-01},

journal = {Geochemistry Geophysics Geosystems G3},

volume = {6},

number = {1},

pages = {1--12},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2004,

title = {The cosmic Molybdenum-Ruthenium isotope correlation},

author = {N. Dauphas and A. M. Davis and B. Marty and L. Reisberg},

doi = {10.1016/j.epsl.2004.07.026},

year  = {2004},

date = {2004-01-01},

journal = {Earth and Planetary Science Letters},

volume = {226},

number = {3-4},

pages = {465--475},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas+Marty2004,

title = {textquotelefttextquoteleftA large secular variation in the nitrogen isotopic composition of the atmosphere since the Archaean?textquoterighttextquoteright: response to a comment on textquotelefttextquoteleftThe nitrogen record of crust-mantle interaction and mantle convection from Archaean to presenttextquoterighttextquoteright by R. Kerrrich and Y. Jia},

author = {N. Dauphas and B. Marty},

doi = {10.1016/j.epsl.2004.07.005},

year  = {2004},

date = {2004-01-01},

journal = {Earth and Planetary Science Letters},

volume = {225},

number = {3-4},

pages = {441--450},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2004_2,

title = {Clues from Fe isotope variations on the origin of early Archean BIFs from Greenland},

author = {N. Dauphas and M. Van Zuilen and M. Wadhwa and A. M. Davis and B. Marty and P. E. Janney},

doi = {10.1126/science.1104639},

year  = {2004},

date = {2004-01-01},

journal = {Science},

volume = {306},

number = {5704},

pages = {2077--2080},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hashizume_etal2004,

title = {Protosolar carbon isotopic composition: implications for the origin of meteoritic organics},

author = {K. Hashizume and M. Chaussidon and B. Marty},

doi = {10.1086/379637},

year  = {2004},

date = {2004-01-01},

journal = {The Astrophysical Journal},

volume = {600},

number = {1},

pages = {480--484},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Levresse_etal2004,

title = {Osmium, sulphur, and helium isotopic results from the giant Neoproterozoic epithermal Imiter silver deposit, Morocco: evidence for a mantle source},

author = {G. Levresse and A. Cheilletz and D. Gasquet and L. Reisberg and E. Deloule and B. Marty and K. Kyser},

doi = {10.1016/j.chemgeo.2004.02.004},

year  = {2004},

date = {2004-01-01},

journal = {Chemical Geology},

volume = {207},

number = {1-2},

pages = {59--79},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Yokochi+Marty2004,

title = {A determination of the neon isotopic composition of deep mantle},

author = {R. Yokochi and B. Marty},

doi = {10.1016/j.epsl.2004.06.010},

year  = {2004},

date = {2004-01-01},

journal = {Earth and Planetary Science Letters},

volume = {225},

number = {1-2},

pages = {77--88},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alon_etal2003,

title = {Nitrogen isotopic composition of macromolecular organic matter in interplanetary dust particles},

author = {J. Al\'{e}on and F. Robert and M. Chaussidon and B. Marty},

doi = {10.1016/S0016-7037(03)00170-4},

year  = {2003},

date = {2003-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {67},

number = {19},

pages = {3773--3783},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Becker_etal2003,

title = {Isotopic signatures of volatiles in terrestrial planets},

author = {R. H. Becker and R. N. Clayton and E. M. Galimov and H. Lammer and B. Marty and R. O. Pepin and R. Wieler},

doi = {10.1023/A:1024610325914},

year  = {2003},

date = {2003-01-01},

journal = {Space Science Reviews},

volume = {106},

number = {3-4},

pages = {377--410},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2003,

title = {Short-lived p-nuclides in the early solar system and implications on the nucleosynthetic role of X-ray binaries},

author = {N. Dauphas and T. Rauscher and B. Marty and L. Reisberg},

doi = {10.1016/S0375-9474(03)00934-5},

year  = {2003},

date = {2003-01-01},

journal = {Nuclear Physics. A},

volume = {719},

pages = {287c-295c},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kallenbach_etal2003,

title = {Sun and Protosolar Nebula},

author = {R. Kallenbach and F. Robert and J. Geiss and E. Herbst and H. Lammer and B. Marty and T. J. Millar and U. Ott and R. O. Pepin},

doi = {10.1023/A:1024658209076},

year  = {2003},

date = {2003-01-01},

journal = {Space Science Reviews},

volume = {106},

number = {3-4},

pages = {319--376},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Libourel_etal2003,

title = {Nitrogen solubility in basaltic melt. Part I. Effect of oxygen fugacity},

author = {G. Libourel and B. Marty and F. Humbert},

doi = {10.1016/S0016-7037(03)00259-X},

year  = {2003},

date = {2003-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {67},

number = {21},

pages = {4123--4135},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty+Dauphas2003,

title = {The nitrogen record of crust-mantle interaction and mantle convection from Archean to Present},

author = {B. Marty and N. Dauphas},

doi = {10.1016/S0012-821X(02)01108-1},

year  = {2003},

date = {2003-01-01},

journal = {Earth and Planetary Science Letters},

volume = {206},

pages = {397--410},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty+Dauphas2003_2,

title = {textquotelefttextquoteleftNitrogen isotopic compositions of the present mantle and the Archean biospheretextquoterighttextquoteright: Reply to comment by Pierre Cartigny and Magali Ader},

author = {B. Marty and N. Dauphas},

doi = {10.1016/S0012-821X(03)00506-5},

year  = {2003},

date = {2003-01-01},

journal = {Earth and Planetary Science Letters},

volume = {216},

pages = {433--439},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2003,

title = {Geochemical evidence for efficient aquifer isolation over geological timeframes},

author = {B. Marty and S. Dewonck and C. France-Lanord},

doi = {10.1038/nature01966},

year  = {2003},

date = {2003-01-01},

journal = {Nature},

volume = {425},

number = {6953},

pages = {55--58},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty_etal2003_2,

title = {Nitrogen isotopes on the Moon: Archives of the solar and planetary contributions to the inner Solar System through time},

author = {B. Marty and K. Hashizume and M. Chaussidon and R. Wieler},

doi = {10.1023/A:1024689721371},

year  = {2003},

date = {2003-01-01},

journal = {Space Science Reviews},

volume = {106},

number = {1-4},

pages = {175--196},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mathew_etal2003,

title = {Volatiles (nitrogen, noble gases) in recently discovered SNC meteorites, extinct radioactivities and evolution},

author = {K. J. Mathew and B. Marty and K. Marti and L. Zimmermann},

doi = {10.1016/S0012-821X(03)00365-0},

year  = {2003},

date = {2003-01-01},

journal = {Earth and Planetary Science Letters},

volume = {214},

number = {1-2},

pages = {27--42},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alon_etal2002,

title = {Oxygen isotopes in single micrometer-sized quartz grains: tracing the source of Saharan dust over long distance atmospheric transport},

author = {J. Al\'{e}on and M. Chaussidon and B. Marty and L. Lothar-Schutz and R. Jaenicke},

doi = {10.1016/S0016-7037(02)00940-7},

year  = {2002},

date = {2002-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {66},

number = {19},

pages = {3351--3365},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ayalew_etal2002,

title = {Source, genesis and timing of giant ignimbrite deposits associated with Ethiopian continental flood basalts},

author = {D. Ayalew and P. Barbey and B. Marty and L. Reisberg and G. Yirgu and R. Pik},

doi = {10.1016/S0016-7037(01)00834-1},

year  = {2002},

date = {2002-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {66},

number = {8},

pages = {1429--1448},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ayalew_etal2002_2,

title = {Origin and timing of Ethiopian Ignimbrites},

author = {D. Ayalew and P. Barbey and B. Marty and L. Reisberg and G. Yirgu and R. Pik},

year  = {2002},

date = {2002-01-01},

journal = {Geological Journal},

volume = {36},

pages = {409--419},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas+Marty2002,

title = {The late bombardment of Earth and Solar System dynamics},

author = {N. Dauphas and B. Marty},

year  = {2002},

date = {2002-01-01},

journal = {Journal of Geophysical Research (Planets)},

volume = {107},

pages = {E12-11E12},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2002,

title = {Molybdenum nucleosynthetic dichotomy revealed in primitive meteorites},

author = {N. Dauphas and B. Marty and L. Reisberg},

doi = {10.1086/340580},

year  = {2002},

date = {2002-01-01},

journal = {Astrophysical Journal},

volume = {569},

pages = {L139-L142},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2002_2,

title = {Inference on terrestrial genesis from molybdenum isotope systematics},

author = {N. Dauphas and B. Marty and L. Reisberg},

year  = {2002},

date = {2002-01-01},

journal = {Geophysical Research Letters},

volume = {29},

number = {6},

pages = {8-1},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2002_3,

title = {Molybdenum evidence for inherited large scale isotope heterogeneity of the Protosolar Nebula},

author = {N. Dauphas and B. Marty and L. Reisberg},

doi = {10.1086/324597},

year  = {2002},

date = {2002-01-01},

journal = {The Astrophysical Journal},

volume = {565},

pages = {640--644},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2002_4,

title = {An alternative explanation for the distribution of highly siderophile elements in Earth},

author = {N. Dauphas and L. Reisberg and B. Marty},

year  = {2002},

date = {2002-01-01},

journal = {Geochemical Journal},

volume = {36},

number = {4-5},

pages = {409--419},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Hashizume_etal2002,

title = {Analyses of nitrogen and argon in single lunar grains: towards a quantification of the asteroidal contribution to planetary surfaces},

author = {K. Hashizume and B. Marty and R. Wieler},

doi = {10.1016/S0012-821X(02)00781-1},

year  = {2002},

date = {2002-01-01},

journal = {Earth and Planetary Science Letters},

volume = {202},

number = {2},

pages = {201--216},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marty+Marti2002,

title = {Signatures of early differentiation of Mars},

author = {B. Marty and K. Marti},

doi = {10.1016/S0012-821X(01)00612-4},

year  = {2002},

date = {2002-01-01},

journal = {Earth and Planetary Science Letters},

volume = {196},

number = {3-4},

pages = {251--264},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pinti+Marty2002,

title = {La mer est tomb\'{e}e du ciel},

author = {D. L. Pinti and B. Marty},

year  = {2002},

date = {2002-01-01},

journal = {La Recherche},

volume = {355},

number = {Special},

pages = {14--17},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Rvillon_etal2002,

title = {Heterogeneity of the Caribbean plateau mantle source: Sr, O and He isotopic compositions of olivine and clinopyroxene from Gorgona Island},

author = {S. R\'{e}villon and C. Chauvel and N. T. Arndt and R. Pik and F. Martineau and S. Fourcade and B. Marty},

doi = {10.1016/S0012-821X(02)01003-8},

year  = {2002},

date = {2002-01-01},

journal = {Earth and Planetary Science Letters},

volume = {205},

number = {1-2},

pages = {91--106},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Tolstikhin_etal2002,

title = {Rare gas isotopes and parent trace elements in ultrabasic-alkaline-carbonatite complexes, Kola Peninsula : identification of lower mantle plume component},

author = {I. N. Tolstikhin and I. L. Kamensky and B. Marty and V. A. and Nivin},

doi = {10.1016/S0016-7037(01)00807-9},

year  = {2002},

date = {2002-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {66},

number = {5},

pages = {881--901},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dauphas_etal2001,

title = {Solvent extraction, ion chromatography, and mass spectrometry of Molybdenum isotopes},

author = {N. Dauphas and L. Reisberg and B. Marty},

doi = {10.1021/ac000998g},

year  = {2001},

date = {2001-01-01},

journal = {Analytical Chemistry},

volume = {73},

pages = {2613--2616},

keywords = {},

pubstate = {published},

tppubtype = {article}

}