Publications CRPG

@article{Hopp_etal2022,

title = {Ryugu’s nucleosynthetic heritage from the outskirts of the Solar System},

author = {T. Hopp and N. Dauphas and al. and L. Piani },

doi = {10.1126/sciadv.add8141},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Science Advances},

volume = {8},

pages = {eads8141},

abstract = {Little is known about the origin of the spectral diversity of asteroids and what it says about conditions in the proto-planetary disk. Here, we show that samples returned from Cb-type asteroid Ryugu have Fe isotopic anomalies indistinguishable from Ivuna-type (CI) chondrites, which are distinct from all other carbonaceous chondrites. Iron isotopes, therefore, demonstrate that Ryugu and CI chondrites formed in a reservoir that was different from the source regions of other carbonaceous asteroids. Growth and migration of the giant planets destabilized nearby planetesimals and ejected some inward to be implanted into the Main Belt. In this framework, most carbonaceous chondrites may have originated from regions around the birthplaces of Jupiter and Saturn, while the distinct isotopic composition of CI chondrites and Ryugu may reflect their formation further away in the disk, owing their presence in the inner Solar System to excitation by Uranus and Neptune.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Dallai_etal2022,

title = {Quartz-bearing rhyolitic melts in the Earth’s mantle},

author = {L. Dallai and G. Bianchini and R. Avanzinelli and E. Deloule and C. Natali and M. Gaeta and A. Cavallo and S. Conticelli},

doi = {10.1038/s41467-022-35382-3},

year  = {2022},

date = {2022-01-01},

journal = {Nature Communications},

abstract = {The occurrence of rhyolite melts in the mantle has been predicted by high pressure-high temperature experiments but never observed in nature. Here we report natural quartz-bearing rhyolitic melt inclusions and interstitial glass within peridotite xenoliths. The oxygen isotope composition of quartz crystals shows the unequivocal continental crustal derivation of these melts, which approximate the minimum composition in the quartz-albite-orthoclase system. Thermodynamic modelling suggests rhyolite was originated from partial melting of near-anhydrous garnet-bearing metapelites at temperatures textasciitilde1000thinspacetextdegreeC and interacted with peridotite at pressure textasciitilde1thinspaceGPa. Reaction of rhyolite with olivine converted lherzolite rocks into orthopyroxene-domains and orthopyroxene + plagioclase veins. The recognition of rhyolitic melts in the mantle provides direct evidence for element cycling through earth’s reservoirs, accommodated by dehydration and melting of crustal material, brought into the mantle by subduction, chemically modifying the mantle source, and ultimately returning to surface by arc magmatism.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Combes_etal2022,

title = {Integrated geological-geophysical investigation of gold-hosting Rhyacian intrusions (Yaou, French Guiana), from deposit-to district-scale},

author = {M. Combes and A. Eglinger and A. S. Andre-Mayer and Y. teitler and M. Jessell and A. Zeh and L. Reisberg and A. Heuret and P. Gilbert},

doi = {10.1016/j.jsames.2021.103708},

year  = {2022},

date = {2022-01-01},

journal = {Journal of South American Earth Sciences},

volume = {114},

pages = {103708},

abstract = {The mineral system concept, which combines integrated information from all kinds of geological and geophysical studies, is a very useful approach to predict and locate structures and lithologies potentially associated with gold mineralization at all scales (i.e., upscaling from craton-to district-to camp-to deposit-scale). This is demonstrated in this study where the Yaou deposit, located in French Guiana within Rhyacian terranes, formed and deformed during the Trans-Amazonian orogenic cycle (ca. 2600-1950 Ma), is used as a case study. The deposit comprises numerous intrusions hosting the bulk of the high-grade gold mineralization at Yaou, associated with a quartz-carbonate veining system. Both intrusive and gold events are dated in order to constrain Yaou in the regional litho-structural framework. Spatially associated with the Central Yaou Shear Zone (CYSZ), one of the quartz monzodiorite yields a U--Pb zircon age of 2131 textpm 6 Ma, supra-chondritic $epsilon$Hft of ca. 2.5, and Hf model ages at ca. 2.6--2.4 Ga. These data suggest Paleoproterozoic rock formation due to reworking of juvenile crust, derived from the depleted mantle during the late Archean to early Paleoproterozoic. The main and economic gold event hosted by the quartz monzodiorite is dated at 2105 textpm 25 Ma by Re--Os isotope analyses of Au-bearing pyrite, representing the first date for gold mineralization in French Guiana. A multi-scale approach using airborne magnetic and radiometric data allows to better understand the spatial distribution of the intrusions and possibly associated shear zones, both related to gold mineralization events. The intrusions and associated shear zones are interpreted as being parallel along a N60textdegree trend and replicated laterally toward the northwest. A temporal association is defined between the shearing deformation and the magmatic event, both being synchronous with a possibility of pre-shearing intrusion and a protracted magmatic phase active while shearing. The Yaou-type intrusion-hosted mineralization can be targeted along these N60textdegree-striking structures. This integrated approach opens some targeting options, previously unrecognized within the southern Paramaca Greenstone Belt.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Davenport_etal2022,

title = {Decoupling of physical and chemical erosion in the Himalayas revealed by radiogenic Ca isotopes},

author = {J. Davenport and G. Caro and C. France-Lanord},

doi = {10.1016/j.gca.2022.10.031},

year  = {2022},

date = {2022-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {338},

pages = {199--219},

abstract = {Determining the rate of CO2 consumption associated with the Himalayan uplift is an essential prerequisite to understanding climate evolution throughout the Cenozoic. The riverine fluxes of dissolved calcium can be used to quantify uptakes of atmospheric CO2 by chemical weathering, but this approach requires deciphering the silicate-derived Ca flux from the generally dominant carbonate-derived Ca flux. Here we present high-precision radiogenic calcium (40Ca) analyses of bank sediments and dissolved loads from a network of rivers in central Nepal Himalaya and Bangladesh, to constrain the sources and relative contributions of carbonate and silicate-derived calcium to the dissolved loads of Himalayan rivers. Calcium isotope analyses were performed in multidynamic mode by thermal ionization mass spectrometry, yielding an external precision of textpm0.4 $epsilon$-units (2 S.D.). Our results show that silicate catchments exposed in the Himalayan range have variably radiogenic $epsilon$40Ca compositions relative to seawater, ranging from +0.7 in the TSS to +14 in the LH. In contrast, sedimentary carbonates, including metamorphosed dolomites with variably radiogenic 87Sr/86Sr, exhibit uniform $epsilon$40Ca identical to modern seawater. The homogeneous $epsilon$40Ca composition of sedimentary carbonates confirms the relative resistance of radiogenic Ca signatures to post-depositional alteration and provides a robust baseline against which the contribution of silicate weathering to the riverine Ca flux can be evaluated. Dissolved load compositions of rivers draining LH catchments exhibit $epsilon$40Ca values ranging from 0 to +11, reflecting the relative contribution of unradiogenic carbonates and highly radiogenic metapelitic units of the LH sequence. HHC rivers show a more moderate range, from 0.5 to +2, reflecting the less radiogenic composition of HHC paragneisses. Himalayan front rivers draining all three lithotectonic units of the Himalayan range exhibit moderately radiogenic $epsilon$40Ca, ranging from +0.5 to +1.4 and overall similar to the average composition of the Ganga mainstream in Bangladesh. Using an approach combining conventional alkalinity budgets with isotopic mass balance calculations, we show that the dissolved silicate Ca flux of major Himalayan front rivers is primarily derived from the weathering of metapelitic rocks of the lesser Himalaya. In contrast, regions of the high range that generate the bulk of the detrital flux to the Gangetic floodplain represent a subordinate source of silicate-derived Ca. This result demonstrates that the chemical weathering of Ca-silicates in the Himalayan system is decoupled from physical erosion. The extensive erosional activity observed in the high range may thus play a limited role in promoting CO2 consumption and global cooling by silicate weathering.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Clift_etal2022,

title = {A synthesis of monsoon exploration in the Asian marginal seas},

author = {P. D. Clift and C. Betzler and S. C. Clemens and B. Christensen and G. P. Eberli and C. France-Lanord},

doi = {10.5194/sd-31-1-2022},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Scientific Drilling},

volume = {31},

pages = {1--29},

abstract = {The International Ocean Discovery Program (IODP) conducted a series of expeditions between 2013 and 2016 that were designed to address the development of monsoon climate systems in Asia and Australia. Significant progress was made in recovering Neogene sections spanning the region from the Arabian Sea to the Sea of Japan and southward to western Australia. High recovery by advanced piston corer (APC) has provided a host of semi-continuous sections that have been used to examine monsoonal evolution. Use of the half-length APC was successful in sampling sand-rich sediment in Indian Ocean submarine fans. The records show that humidity and seasonality developed diachronously across the region, although most regions show drying since the middle Miocene and especially since \^{a}`uthinspace4thinspaceMa, likely linked to global cooling. A transition from C3 to C4 vegetation often accompanied the drying but may be more linked to global cooling. Western Australia and possibly southern China diverge from the general trend in becoming wetter during the late Miocene, with the Australian monsoon being more affected by the Indonesian Throughflow, while the Asian monsoon is tied more to the rising Himalaya in South Asia and to the Tibetan Plateau in East Asia. The monsoon shows sensitivity to orbital forcing, with many regions having a weaker summer monsoon during times of northern hemispheric Glaciation. Stronger monsoons are associated with faster continental erosion but not weathering intensity, which either shows no trend or a decreasing strength since the middle Miocene in Asia. Marine productivity proxies and terrestrial chemical weathering, erosion, and vegetation proxies are often seen to diverge. Future work on the almost unknown Paleogene is needed, as well as the potential of carbonate platforms as archives of paleoceanographic conditions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Banerjee_etal2022,

title = {Fractionation of trace and platinum-group elements during metamorphism of komatiitic chromites from the early Archean Gorumahishani greenstone belt, Singhbhum Craton (eastern India)},

author = {R. Banerjee and S. K. Mondal and L. Reisberg and J. W. Park},

doi = {10.1007/s00410-022-01943-4},

year  = {2022},

date = {2022-01-01},

journal = {Contributions to Mineralogy and Petrology},

volume = {177},

number = {75},

abstract = {It is well established that the major and minor element contents of chromites are subject to change during greenschist to amphibolite facies metamorphism. During upper amphibolite facies metamorphism, chromite can be completely converted to chrome magnetite. However, not all elements are affected to the same degree, the concentrations of +2 ions (e.g. Zn, Co, Mn) being particularly vulnerable to modification. The degree to which trace elements, particularly the platinum-group elements (PGE), are affected has not been closely examined. The compositions and textures of chromites from komatiites of the Gorumahishani greenstone belt of the Singhbhum Craton (India) have experienced a range of metamorphic conditions from greenschist to amphibolite facies, providing the opportunity to study the changes of trace and platinum-group element composition with metamorphic grade. Five types of altered chromites are identified from the komatiitic suite of rocks in thethinspacetextasciitilde120-km-long greenstone belt. The type-I chromites are non-porous and characterized by the least modified cores. These chromites are mostly present in the northern Maharajgunj-Tua Dungri section where rocks show metamorphism from greenschist to greenschist-amphibolite transition facies. The type-II and type-III chromites are porous and mostly found in the southern Kapili section of the greenstone belt where rocks show metamorphism up to the mid-amphibolite facies. Type-IV and type-V chromites are completely modified to ferritchromit and chrome magnetite, respectively, and are present in the komatiitic rocks from the entire greenstone belt. The central cores of the type-I and type-II grains have relatively higher concentrations of mobile trace elements (e.g. Zn, Co, and Mn) with higher Mg# [Mg/(Mgthinspace+thinspaceFe2+)], lower Cr# [Cr/(Crthinspace+thinspaceAl)], and lower Fe3+/R3+ (R3+thinspace=thinspaceFe3+thinspace+thinspaceCr3+thinspace+thinspaceAl3+) ratios than their respective rims. Significantly higher concentrations of the immobile trace elements (e.g. Ti and V) in the cores of the type-II grains relative to their chrome magnetite rims from the Kapili section and to the type-I varieties from other sections might be due to the metamorphism of the komatiitic rocks under higher-grade conditions (amphibolite facies). In situ LA-ICPMS analysis for PGE reveals a relatively higher concentration of Ru and Rh in the rims of the type-I chromites than in the cores which is due to the diffusion of these elements from the normal spinel structure of the cores towards the bivalent octahedral sites of the inverse spinel structure of the chrome magnetite rims during metamorphic processes. The lower concentrations of Os, Ir, Ru, and Rh in the cores of the type-II chromites from the Kapili section might be related to the metamorphism of the rocks under higher-grade conditions that facilitated the diffusion of these elements to associated sulphide or platinum-group mineral or alloy phases. The calculated partition coefficients of Sc, Ti, V, Mn, Ni, Ga, Os, Ir, Ru, and Rh from the least altered chromite cores assuming equilibrium with the parental komatiitic melt also suggest the variable effects of metamorphism when compared with global experimental and empirical values of the natural samples.},

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{Barosch_etal2022,

title = {Presolar Stardust in Asteroid Ryugu},

author = {J. Barosch and L. R. Nittler and J. Wang and C. M. O. D’Alexander and B. T. De Gregorio and L. Piani},

doi = {10.3847/2041-8213/ac83bd},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {The Astrophysical Journal Letters},

volume = {935},

number = {L3},

abstract = {We have conducted a NanoSIMS-based search for presolar material in samples recently returned from C-type asteroid Ryugu as part of JAXA\^{E}¼s Hayabusa2 mission. We report the detection of all major presolar grain types with O- and C-anomalous isotopic compositions typically identified in carbonaceous chondrite meteorites: 1 silicate, 1 oxide, 1 O-anomalous supernova grain of ambiguous phase, 38 SiC, and 16 carbonaceous grains. At least two of the carbonaceous grains are presolar graphites, whereas several grains with moderate C isotopic anomalies are probably organics. The presolar silicate was located in a clast with a less altered lithology than the typical extensively aqueously altered Ryugu matrix. The matrix-normalized presolar grain abundances in Ryugu are 4.8 2.6 4.7 ?\"{A}¬ + ppm for O-anomalous grains, 25 5 6 ?\"{A}¬ + ppm for SiC grains, and 11 3 5 ?\"{A}¬ + ppm for carbonaceous grains. Ryugu is isotopically and petrologically similar to carbonaceous Ivuna-type (CI) chondrites. To compare the in situ presolargrain abundances of Ryugu with CI chondrites, we also mapped Ivuna and Orgueil samples and found a total of 15 SiC grains and 6 carbonaceous grains. No O-anomalous grains were detected. The matrix-normalized presolar grain abundances in the CI chondrites are similar to those in Ryugu: 23 6 7 ?\"{A}¬ + ppm SiC and 9.0 3.65.4 ?\"{A}¬ + ppm carbonaceous grains. Thus, our results provide further evidence in support of the Ryugu--CI connection. They also reveal intriguing hints of small-scale heterogeneities in the Ryugu samples, such as locally distinct degrees of alteration that allowed the preservation of delicate presolar material.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Jegal_etal2022,

title = {Characterisation of reference materials for In situ Rb-Sr dating by LA-ICP-MS/MS},

author = {Y. Jegal and C. Zimmermann and L. Reisberg and D. Yeghicheyan and C. Cloquet and C. Peiffert and M. Gerardin and E. Deloule and J. Mercadier},

doi = {10.1111/ggr.12456},

year  = {2022},

date = {2022-01-01},

journal = {Geostandards and Geoanalytical Research},

volume = {46},

number = {4},

pages = {645--671},

abstract = {We present Rb and Sr mass fraction and 87Sr/86Sr isotope ratio measurement results for four reference materials (RMs) obtained from the Service d’Analyse des Roches et des Min\'{e}raux (SARM), Nancy, France: Mica-Mg, Mica-Fe, GL-O and FK-N. These four RMs have different chemical compositions spanning the range of those of most K-bearing feldspars and micas, making them potential calibration materials for in situ Rb-Sr dating of natural minerals by LA-ICP-MS/MS. Selected grains and flakes from the four RMs present variable degrees of heterogeneity observable by SEM-EDS and EPMA imaging, and chemical mapping. This heterogeneity is mainly related to inclusions of minerals within flakes and grains and to chemical substitutions linked to crystallographic control and alteration processes. The Mica-Mg RM is the least affected. The powders available at the SARM were analysed by ID-TIMS (87Sr/86Sr and Sr) and ID-MC-ICP-MS (Rb) after digestion and separation. The mean 87Rb/86Sr ratios are 155.6thinspacetextpmthinspace4.7% (2s, as for other RMs) for Mica-Mg, 1815thinspacetextpmthinspace14% for Mica-Fe, 36.2thinspacetextpmthinspace11% for GL-O and 69.9thinspacetextpmthinspace5.9% for FK-N. The mean 87Sr/86Sr ratios are 1.8622thinspacetextpmthinspace0.36% (2s, as for other RMs) for Mica-Mg, 7.99thinspacetextpmthinspace13% for Mica-Fe, 0.75305thinspacetextpmthinspace0.12% for GL-O, and 1.2114thinspacetextpmthinspace0.17% for FK-N. The four RMs each show dispersion in 87Sr/86Sr and Rb and Sr mass fractions, to degrees that differ between RMs and that reflect the heterogeneity of their original crystals. The most heterogeneous RMs are GL-O and Mica-Fe. The calculated mean Rb-Sr isotopic ages are 521thinspacetextpmthinspace24 Ma for Mica-Mg, 287thinspacetextpmthinspace55 Ma for Mica-Fe, 89.2thinspacetextpmthinspace9.9 Ma for GL-O and 512thinspacetextpmthinspace30 Ma for FK-N. The proposed age for Mica-Fe may be unreliable due to the elevated dispersion of individual analysis linked to the highly radiogenic composition of the biotite and to the presence of numerous mineral inclusions. We recommend use of these proposed working values of 87Sr/86Sr and 87Rb/86Sr ratios and associated uncertainties when using the four RMs for in situ Rb-Sr dating by LA-ICP-MS/MS. The availability of these four well-characterised RMs will allow progress in the development and application of the Rb-Sr dating approach by LA-ICP-MS/MS.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Lacroix_etal2022,

title = {SAR and optical images correlation illuminates post\^{a}€‘seismic landslide motion after the Mw 7.8 Gorkha earthquake (Nepal)},

author = {S. Lacroix and T. Gavillon and C. Bouchant and J. Lav\'{e} and J. L. Mugnier and S. Dhungel and F. Vernier},

doi = {10.1038/s41598-022-10016-2},

year  = {2022},

date = {2022-01-01},

journal = {Scientific Reports},

volume = {12},

number = {6266},

abstract = {In the days to weeks following an earthquake, landslides can display specific post-seismic motions,including delayed initiations and post-seismic relaxations. These motions have an uncertain origin, sometimes attributed to specificities of the landslide basal interface or to fluid transports in the landslide basal shear zone. Here we address this question, by documenting the co- and post-seismic motions of slow-moving landslides accelerated by the Gorkha earthquake (Mw 7.8, 25/04/2015,Nepal). We detect 11 slow-moving landslides over an area of 750 km2 in the near field of the earthquake, and monitor their motions thanks to a time-series of Pl\'{e}iades optical satellite images and SAR Sentinel-1 images. The post-seismic landslide motions are much larger than the co-seismic ones, reaching up to 34 textpm 0.6 m accommodated over 2 months. A delayed initiation of several days (\> 4days) is also measured for at least two of the landslides. We analyze our findings in regards with all the previous observations on slow-moving landslides accelerated by earthquakes, and propose that the post-seismic motions are caused by diffusion of groundwater from co-seismic material contraction up to the landslide basal shear zone or from internal landslide reconfiguration. Our observations stronglysuggest the main control of the hydrology in the landslide processes under seismic forcings.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Moynier_etal2022,

title = {The Solar System calcium isotopic composition inferred from Ryugu samples},

author = {F. Moynier and W. Dai and T. Yokoyama and L. Piani},

doi = {10.7185/geochemlet.2238},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Geochemical Perspectives Letters},

volume = {24},

abstract = {The Hayabusa2 spacecraft has returned samples from the Cb-type asteroid (162173) Ryugu to Earth. Previous petrological and chemical analyses support a close link between Ryugu and CI chondrites that are presumed to be chemically the most primitive meteorites with a solar-like composition. However, Ryugu samples are highly enriched in Ca compared to typical CI chondrites. To identify the cause of this discrepancy, here we report stable Ca isotopic data (expressed as $delta$44/40CaSRM915a) for returned Ryugu samples collected from two sites. We found that samples from both sites have similar $delta$44/40CaSRM915a (0.58thinspacetextpmthinspace0.03 texttenthousand and 0.55thinspacetextpmthinspace0.08 texttenthousand, 2 s.d.) that fall within the range defined by CIs. This isotopic similarity suggests that the Ca budget of CIs and Ryugu samples is dominated by carbonates, and the variably higher Ca contents in Ryugu samples are due to the abundant carbonates. Precipitation of carbonates on Ryugu likely coincided with a major episode of aqueous activity dated to have occurred \^{a}`u5 Myr after Solar System formation. Based on the pristine Ryugu samples, the average $delta$44/40CaSRM915a of the Solar System is defined to be 0.57thinspacetextpmthinspace0.04 texttenthousand (2 s.d.).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Florin_etal2022,

title = {Abundances of siderophile elements in H-chondrite metal grains: Implications for the origin of metal in unequilibrated ordinary chondrites},

author = {G. Florin and O. Alard and B. Luais and T. Rushmer},

doi = {10.1016/j.gca.2022.11.014},

year  = {2022},

date = {2022-01-01},

journal = {Geochimica et Cosmochimica Acta},

volume = {341},

pages = {1--15},

abstract = {Understanding the evolution of metal in the protoplanetary disk is necessary to constrain the first steps of metal-silicate segregation and the early stages of the evolution of the protoplanetary disk. We measured the siderophile elemental compositions (PGE, Ni, Co, Fe, Cu, Ga, Ge) of individual metal grains in H ordinarychondrites by laser ablation inductively coupled plasma mass spectrometry to investigate their formation. We analyzed unequilibrated ordinary chondrites (H3) to constrain processes affecting the metal before accretion, and inferred the effects of metamorphism by comparing their elemental compositions to those of equilibrated chondrites (H4--H6). Our results highlight large variations of refractory (Re, Os, W, Ir, Ru, Mo, Pt) and moderately volatile siderophile element (Pd, Au, Ga, Ge) concentrations among metal grains in H3 samples that permit to classify them according to their Ge/Ir ratios and HSE contents. These intergrain variations are progressively homogenized in H4--H6 samples due to their increasing degrees of metamorphism. To constrain the origin of the metal, we modeled its evolution during melting and crystallization. Our melting model of a single metallic precursor containing 1.5 wt% C and up to 12 wt% S reproduces well the observed range of siderophile element compositions in the metal. Metal grains show a range of W, Mo, and Ga compositions that we interpret to reflect various local (grain-scale) oxidation states during the melting event(s) due to the heterogeneous distribution of various oxidizing components within the precursors. The very similar HSE compositions of H and L/LL metal grains suggests that the variations of bulk metal abundance and HSE concentrations observed among the different classes of ordinary chondrites (H, L, LL) result from the heterogeneous physical distribution of a relatively chemically homogeneous metal component among OC parent bodies, and not from a chemical (sensu lato) gradient between H and LL chondrites.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marrocchi+Beck2022,

title = {The quest for the water},

author = {Y. Marrocchi and P. Beck},

doi = {10.2138/gselements.18.3.149},

year  = {2022},

date = {2022-01-01},

journal = {Elements},

volume = {18},

pages = {149--153},

abstract = {Water played a key role in shaping the Solar System---from the formation of early solids to the processes of planetary and moon formation. The presence of water in molecular clouds influences the initial abundance and distribution of water in the circumsolar disk, which, in turn, affected the water budget of the terrestrial planets and, therefore, their geological activity and habitability. On Earth, surficial and deep-water cycles have largely governed the planet’s geodynamical and geochemical evolution. This issue focuses on the past and present distribution of water within the Solar System and how this important molecule affects astrophysical and geological processes.},

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{Izidoro+Piani2022,

title = {Origin of water in the terrestrial planets: Insights from meteorite data and planet formation models},

author = {A. Izidoro and L. Piani},

doi = {10.2138/gselements.18.3.181},

year  = {2022},

date = {2022-01-01},

journal = {Elements},

volume = {18},

number = {3},

pages = {181--186},

abstract = {Water condensed as ice beyond the water snowline, the location in the Sun’s natal gaseous disk where temperatures were below 170 K. As the disk evolved and cooled, the snowline moved inwards. A low temperature in the terrestrial planet-forming region is unlikely to be the origin of water on the planets, and the distinct isotopic compositions of planetary objects formed in the inner and outer disks suggest limited early mixing of inner and outer Solar System materials. Water in our terrestrial planets has rather been derived from H-bearing materials indigenous to the inner disk and delivered by water-rich planetesimals formed beyond the snowline and scattered inwards during the growth, migration, and dynamical evolution of the giant planets.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wolff+Neukampf2022,

title = {Biotite as an indicator of post‑eruptive cryptic alteration in the Battleship Rock Ignimbrite, Valles Caldera, NM, USA},

author = {J. A. Wolff and J. Neukampf},

doi = {10.1007/s00445-022-01609-w},

year  = {2022},

date = {2022-01-01},

journal = {Bulletin of Volcanology},

volume = {89},

pages = {99},

abstract = {The Battleship Rock Ignimbrite of the East Fork Member of the Valles Rhyolite (USA) consists of a variably welded compound cooling unit emplaced in the southern part of the Valles Caldera at 74 ka. At the type locality, the unit was deposited in a narrow paleocanyon and is glassy throughout, with little petrographic evidence for post-eruptive alteration. Biotites from different zones in the ignimbrite at this location, and associated lavas and fallout deposits of the East Fork Member, frequently exhibit low analytical totals (\< 94 wt%; by electron microprobe) that are correlated with potassium (K) depletion and enriched in lithium (Li). These variations between samples are systematically related to the welding profile of theignimbrite. Biotites with low totals are accompanied by groundmass glass with low $delta$18O, which requires high-temperature interaction with meteoric water. The low totals, K depletion, and Li enrichment are therefore attributed to a brief episodeof meteoric-hydrothermal alteration of the cooling tuff immediately following emplacement. The duration of the episode is estimated to be on the order of months or less, constrained by Cs, Rb, and Sr mobility in glass. Additional variations inglass and biotite chemistry are identified as primary, and offer an avenue to deciphering the complex event stratigraphy of the eruption, with implications for hazard potential of future rhyolitic eruptions from Valles Caldera.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zerathe_etal2022,

title = {Cosmogenic 3He and 10Be denudation rates in the Central Andes: Comparison with a natural sediment trap over the last 18 ka},

author = {S. Zerathe and C. Litty and P. H. Blard and F. Delgado and L. Audin and J. Carcaillet and ASTER Team.},

doi = {https://doi.org/10.1016/j.epsl.2022.117869},

year  = {2022},

date = {2022-01-01},

journal = {Earth and Planetary Science Letters},

volume = {599},

pages = {117869},

abstract = {It is of major importance for Earth surface sciences to reconstruct denudation rates in the most precise and accurate way. For this, it can be useful to test on the same setting methods based on different assumptions, such as those relying on geomorphological and geochemical observations. Here, we use an exceptionally suited setting in the Locumba catchment (southwestern Peruvian Andes) that offers the unique opportunity to compare denudation rates derived from in situ cosmogenic 3He and 10Be with a geomorphological sediment budget integrated over the last 18 ka. The sediment budget is estimated by determining the volume of sediment trapped in the Aricota lake that formed 18 ka ago after the occurrence of a giant rockslide dam. We reconstructed the topography of the Locumba valley before the dam emplacement and established that the captured sediment volume is 0.8 textpm 0.1 km3. Considering that the lake-water output is restricted to seepage through the dam and that overflow above the dam never occurred, this volume correctly represents the sediment flux integrated over the last 18 ka. Integrating this volume over the upstream catchment area (\^{a}`u1500 km2), we derived a corresponding mean erosion rate of 30 textpm 9 mm.ka\^{a}ˆ’1. Fluvial sediments feeding the Aricota lake were sampled to derive denudation rates from in-situ cosmogenic 10Be in the silicates and from in-situ cosmogenic 3He in the ferromagnesian minerals. Cosmogenic nuclide denudation rates from the main stream are 30 textpm 2, 33 textpm 2, 21 textpm 1 and 82 textpm 5 mm.ka\^{a}ˆ’1 for the 10Be-quartz, the 10Be-feldspar, the 3He-amphibole and 3He-pyroxene, respectively. The consistency between the cosmogenic nuclide denudation rates derived from 10Be in the silicates and the erosion rate derived from our sediment budget shows that the 10Be accurately estimates of the sediment flux. Additionally, this work provides the first successful application of 10Be-feldspar nuclide-mineral pair to derive catchment-mean denudation rate and demonstrate that 10Be-feldspar can thus be a good alternative in catchments dominated by volcanic rocks with no quartz. The discrepancies observed between the denudation rates derived from the 3He-amphibole and 3He-pyroxene couples require further studies.},

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{Chalot-Prat_etal2022,

title = {Ocean expansion: The role of detachment faults},

author = {F. Chalot-Prat and R. Magott and C. Berthod},

doi = {10.1111/ter.12624},

year  = {2022},

date = {2022-01-01},

number = {00},

pages = {1--8},

abstract = {Detachment faulting at slow spreading ocean ridge axes is recognized as a major surface creation mechanism, yet the structural relationships of these faults with feeder-dykes of on-axis volcanoes remained unresolved. This summary study shows that surface creation leading to ocean widening is exclusively controlled by detachment faults, shallow tracers of tectonic stresses induced by the westward drift of plates. Volcanoes are fed by feeder-dykes following on-axis rotational detachment faults. Once formed volcanoes are dragged along the detachment whose footwall is made of mantle material sometimes hosting gabbro sills. Due to the faster drift of the uppermost lithospheric layer, the feeder-dykes are then intersected by active deeper low-angle detachments, become inactive and are replaced by new ones on-axis. Rooted vertically on either side of the plate boundary, the detachment flexing is all the earlier and more progressive as the faults are far from the axis, positioning gabbro as sills at shallow level within a deformed mantle interspersed with cataclasite horizons. Correlations between shallow and deep lithospheric processes are then clarified},

keywords = {},

pubstate = {published},

tppubtype = {article}

}