2022
|
Auxerre, M., Faure, F., Lequin, D. The effects of superheating and cooling rate on olivine growth in chondritic liquid (Article de journal) Dans: Meteoritics & Planetary Science, p. 1–22, 2022. @article{Auxerre_etal2022,
title = {The effects of superheating and cooling rate on olivine growth in chondritic liquid},
author = {M. Auxerre and F. Faure and D. Lequin},
doi = {10.1111/maps.13830},
year = {2022},
date = {2022-01-01},
journal = {Meteoritics \& Planetary Science},
pages = {1--22},
abstract = {Chondrules, the major constituent of chondrites, are millimeter-sized igneous objects resulting from the crystallization of silicate liquids produced by the partial orcomplete melting of chondritic precursors, whose exact nature remains disputed. Variouschondrule textures are observed as a function of the extent of the initial melting event.Here, we report dynamic crystallization experiments performed with a broad range ofcooling rates (2--750textdegreeCh\^{a}1) from superliquidus or subliquidus initial conditions todemonstrate the control of nucleation on the final chondrule texture. Classical crypto-porphyritic, micro-porphyritic, and porphyritic olivine textures were reproduced insubliquidus experiments in which heterogeneous nucleation dominates. In contrast, we wereunable to reproduce barred olivine textures, regardless of the cooling rates investigated fromsuperliquidus conditions ; instead, macro-porphyritic textures were systematically obtained atlow cooling rates (\<10textdegreeCh\^{a}1). The small number and large size of crystals in the macro-porphyritic texture are consistent with the initial step of superheating and the presence oflong embayments that indicate an initial episode of rapid growth due to delayed nucleation.Crystals then acquired polyhedral shapes during a subsequent episode of slow growth.When the growth rate is too slow to decrease the degree of supersaturation in the liquid, anew episode of rapid growth produces a new generation of melt inclusions},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Chondrules, the major constituent of chondrites, are millimeter-sized igneous objects resulting from the crystallization of silicate liquids produced by the partial orcomplete melting of chondritic precursors, whose exact nature remains disputed. Variouschondrule textures are observed as a function of the extent of the initial melting event.Here, we report dynamic crystallization experiments performed with a broad range ofcooling rates (2--750textdegreeChâ1) from superliquidus or subliquidus initial conditions todemonstrate the control of nucleation on the final chondrule texture. Classical crypto-porphyritic, micro-porphyritic, and porphyritic olivine textures were reproduced insubliquidus experiments in which heterogeneous nucleation dominates. In contrast, we wereunable to reproduce barred olivine textures, regardless of the cooling rates investigated fromsuperliquidus conditions ; instead, macro-porphyritic textures were systematically obtained atlow cooling rates (<10textdegreeChâ1). The small number and large size of crystals in the macro-porphyritic texture are consistent with the initial step of superheating and the presence oflong embayments that indicate an initial episode of rapid growth due to delayed nucleation.Crystals then acquired polyhedral shapes during a subsequent episode of slow growth.When the growth rate is too slow to decrease the degree of supersaturation in the liquid, anew episode of rapid growth produces a new generation of melt inclusions |
Faure, F., Auxerre, M., Casola, V. Slow cooling during crystallisation of barred olivine chondrules (Article de journal) Dans: Earth and Planetary Science Letters, vol. 593, p. 117649, 2022. @article{Faure_etal2022,
title = {Slow cooling during crystallisation of barred olivine chondrules},
author = {F. Faure and M. Auxerre and V. Casola},
doi = {10.1016/j.epsl.2022.117649},
year = {2022},
date = {2022-01-01},
journal = {Earth and Planetary Science Letters},
volume = {593},
pages = {117649},
abstract = {Barred olivine (BO) chondrules are small ferromagnesian silicate igneous droplets with unique dendritic textures that are considered to have formed in the early solar system during one or more brief high-temperature episodes, followed by rapid cooling in a gas. Rapid cooling rates of 100--7200 \^{a}¦C/h during chondrule formation have been proposed based on experiments attempting to reproduce BO crystal textures. However, the BO texture has never truly been reproduced under such rapid cooling conditions. Here, we experimentally show that true BO textures can be produced either after rapid cooling (\>50 \^{a}¦C/h) following by reheating step or by cooling rates slower than 10 \^{a}¦C/h. Regardless of the thermal history considered, the chemical compositions of glass inclusions trapped within olivines of BO chondrules imply a final slow cooling rate one to two orders of magnitude below previous estimates. Such slow cooling rates are consistent with those estimated for plagioclase-bearing porphyritic chondrules and magmatic type-B Ca-Al-rich inclusions, suggesting that slow cooling rates are common to all similar chondritic objects.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Barred olivine (BO) chondrules are small ferromagnesian silicate igneous droplets with unique dendritic textures that are considered to have formed in the early solar system during one or more brief high-temperature episodes, followed by rapid cooling in a gas. Rapid cooling rates of 100--7200 â¦C/h during chondrule formation have been proposed based on experiments attempting to reproduce BO crystal textures. However, the BO texture has never truly been reproduced under such rapid cooling conditions. Here, we experimentally show that true BO textures can be produced either after rapid cooling (>50 â¦C/h) following by reheating step or by cooling rates slower than 10 â¦C/h. Regardless of the thermal history considered, the chemical compositions of glass inclusions trapped within olivines of BO chondrules imply a final slow cooling rate one to two orders of magnitude below previous estimates. Such slow cooling rates are consistent with those estimated for plagioclase-bearing porphyritic chondrules and magmatic type-B Ca-Al-rich inclusions, suggesting that slow cooling rates are common to all similar chondritic objects. |
2021
|
Barbey, P., Grandprat, M., Faure, F. Cordierite-bearing orbicules record bulk assimilation and the pulsating nature of magma ascent : The Lafaye orbicular granite (France) (Article de journal) Dans: Journal of Petrology, p. 1–23, 2021. @article{Barbey_etal2021,
title = {Cordierite-bearing orbicules record bulk assimilation and the pulsating nature of magma ascent : The Lafaye orbicular granite (France)},
author = {P. Barbey and M. Grandprat and F. Faure},
doi = {10.1093/petrology/egab063},
year = {2021},
date = {2021-01-01},
journal = {Journal of Petrology},
pages = {1--23},
abstract = {The Lafaye orbicular body was emplaced in the Villatange tonalite-granodiorite unit of the Gu\'{e}ret magmatic complex (Massif Central, France). It consists of plagioclasic orbicules (4--35cm diameter) embedded in homogeneous cordierite granodiorite. Orbicule cores consist mostly of residual metasedimentary xenoliths or autolithic plagioclasic cumulates. Rims (0.7--8cm thickness) are single- or multi-layered ; layers, mostly comb-textured, comprise alternating sheets dominated by cordierite (XFetextonequarter0.32--0.37) or plagioclase (mostly An25--30). Additional mineral phases are minor biotite (XFetextonequarter0.52 ; AlVItextonequarter0.58--0.92 atoms per formula unit) and interstitial quartz. Plagioclase and cordierite morphologies (needle-like, skeletal, branching or fan-shaped) indicate growth under high initial supersaturation. However, the final polyhedral shapes and primary zoning of many individual plagioclase crystals, as well as evidence of partial recrystallization, imply significant textural maturation. Whole-rock major and trace element data (A/CNKtextonequarter1.12--1.46) and Sr and Nd isotopic compositions (eNd(355 Ma) =-8.6 to -7.4 ; 87Sr/86Sr(355 Ma) =0.7110--0.7147) suggest that the parental magma of the orbicules resulted from bulk assimilation of aluminous metasediments by a Villatange-type granodioritic magma. Heterogeneous nucleation and growth of plagioclase and cordierite around xenoliths/autoliths are interpreted in terms of (1) adiabatic decompression of magma pulses ascending in dykes leading to superheating and resorption of early solids, and (2) volatile exsolution, inducing undercooling, supersaturation, and rim crystallization. The variability of layers (number, thickness, mineral distribution, and texture) is considered to result from oscillatory crystallization combined with variable plagioclase growth rates linked to changes in the degree of supersaturation as a function of the extent of melt degassing, itself linked to magma transfer dynamics},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The Lafaye orbicular body was emplaced in the Villatange tonalite-granodiorite unit of the Guéret magmatic complex (Massif Central, France). It consists of plagioclasic orbicules (4--35cm diameter) embedded in homogeneous cordierite granodiorite. Orbicule cores consist mostly of residual metasedimentary xenoliths or autolithic plagioclasic cumulates. Rims (0.7--8cm thickness) are single- or multi-layered ; layers, mostly comb-textured, comprise alternating sheets dominated by cordierite (XFetextonequarter0.32--0.37) or plagioclase (mostly An25--30). Additional mineral phases are minor biotite (XFetextonequarter0.52 ; AlVItextonequarter0.58--0.92 atoms per formula unit) and interstitial quartz. Plagioclase and cordierite morphologies (needle-like, skeletal, branching or fan-shaped) indicate growth under high initial supersaturation. However, the final polyhedral shapes and primary zoning of many individual plagioclase crystals, as well as evidence of partial recrystallization, imply significant textural maturation. Whole-rock major and trace element data (A/CNKtextonequarter1.12--1.46) and Sr and Nd isotopic compositions (eNd(355 Ma) =-8.6 to -7.4 ; 87Sr/86Sr(355 Ma) =0.7110--0.7147) suggest that the parental magma of the orbicules resulted from bulk assimilation of aluminous metasediments by a Villatange-type granodioritic magma. Heterogeneous nucleation and growth of plagioclase and cordierite around xenoliths/autoliths are interpreted in terms of (1) adiabatic decompression of magma pulses ascending in dykes leading to superheating and resorption of early solids, and (2) volatile exsolution, inducing undercooling, supersaturation, and rim crystallization. The variability of layers (number, thickness, mineral distribution, and texture) is considered to result from oscillatory crystallization combined with variable plagioclase growth rates linked to changes in the degree of supersaturation as a function of the extent of melt degassing, itself linked to magma transfer dynamics |
2020
|
Faure, F. Early silica crust formation in planetesimals by metastable silica-rich liquid immiscibility or cristobalite crystallisation: the possible origin of silica-rich chondrules (Article de journal) Dans: Scientific Reports, 2020. @article{Faure2020,
title = {Early silica crust formation in planetesimals by metastable silica-rich liquid immiscibility or cristobalite crystallisation: the possible origin of silica-rich chondrules},
author = {F. Faure},
doi = {10.1038/s41598-020-61806-5},
year = {2020},
date = {2020-01-01},
journal = {Scientific Reports},
abstract = {The formation and differentiation processes of planetesimals---small bodies in the solar system--- remain actively debated. Planetesimal differentiation is known to have occurred early (\<1.5 Myr after the formation of Ca-Al-rich inclusions), as attested by the ages of iron meteorites. Metal-silicate segregation implies global-scale melting, induced by heat released from short-lived radiogenic isotopes, and the consequent generation of a silicate magma ocean. Thermodynamic calculations show that silicate magma crystallisation would have induced silicate-silicate differentiation, leading to the formation of a thick olivine-dominated textquotelefttextquoteleftmantletextquoterighttextquoteright and a thin basaltic textquotelefttextquoteleftcrusttextquoterighttextquoteright. However, thermodynamic modelling of magma ocean crystallisation does not produce any silica phases. Here I experimentally show that crystallisation of a chondritic liquid does not follow the thermodynamically predicted path. Silica phases are generated early (before 55% differentiation) as a function of initial magma ocean temperature. As cristobalite or liquid silica phases are less dense than residual liquids or olivine, silica phases could have formed proto-crusts that would have acted as buoyant lids at the surfaces of planetesimals, allowing the eventual accretion and preservation of debris (chondrites). Moreover, the destruction of such a crust by impacts could provide an explanation for the origin of the silica reservoir that condensed around some chondrules.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The formation and differentiation processes of planetesimals---small bodies in the solar system--- remain actively debated. Planetesimal differentiation is known to have occurred early (<1.5 Myr after the formation of Ca-Al-rich inclusions), as attested by the ages of iron meteorites. Metal-silicate segregation implies global-scale melting, induced by heat released from short-lived radiogenic isotopes, and the consequent generation of a silicate magma ocean. Thermodynamic calculations show that silicate magma crystallisation would have induced silicate-silicate differentiation, leading to the formation of a thick olivine-dominated textquotelefttextquoteleftmantletextquoterighttextquoteright and a thin basaltic textquotelefttextquoteleftcrusttextquoterighttextquoteright. However, thermodynamic modelling of magma ocean crystallisation does not produce any silica phases. Here I experimentally show that crystallisation of a chondritic liquid does not follow the thermodynamically predicted path. Silica phases are generated early (before 55% differentiation) as a function of initial magma ocean temperature. As cristobalite or liquid silica phases are less dense than residual liquids or olivine, silica phases could have formed proto-crusts that would have acted as buoyant lids at the surfaces of planetesimals, allowing the eventual accretion and preservation of debris (chondrites). Moreover, the destruction of such a crust by impacts could provide an explanation for the origin of the silica reservoir that condensed around some chondrules. |
2019
|
Barbey, P., Faure, F., Paquette, J. L., Pistre, K., Delangle, C., Gremilliet, J. P. Skeletal quartz and dendritic biotite: Witnesses of primary disequilibrium growth textures in an alkali-feldspar granite (Article de journal) Dans: Lithos, vol. 348-349, p. 105202, 2019. @article{Barbey_etal2019,
title = {Skeletal quartz and dendritic biotite: Witnesses of primary disequilibrium growth textures in an alkali-feldspar granite},
author = {P. Barbey and F. Faure and J. L. Paquette and K. Pistre and C. Delangle and J. P. Gremilliet},
doi = {10.1016/j.lithos.2019.105202},
year = {2019},
date = {2019-01-01},
journal = {Lithos},
volume = {348-349},
pages = {105202},
abstract = {We describe a case of S-type alkali-feldspar granite (quartz/K-feldspar/plagioclase/ biotite/garnet �`u 30/35/20/13/2 vol%) showing skeletal and dendritic textures. It consists of three nested units distinguishable by the size of biotite crystals: a first-emplaced unit characterized by small biotite flakes (0.4--9 mm); a second unit with cm-sized biotite platelets (0.3--28 mm) outlining a syn-magmatic foliation; and a third unit formed of large biotite plates (0.7--850 mm) showing dendritic and radial growth patterns.Quartz occurs mostly as rounded to euhedral grains, but also shows complex shapes (serrated outline, re-entrants, etc.). Cathodoluminescence imaging reveals that grains consist of both rounded and skeletal bluish cores (quartz-1) rimmed by reddish overgrowths (quartz-2) that lead locally to the coalescence of neighbouring grains and equilibrated texture. Biotite is poikilitic enclosing dominantly quartz grains but also in lesser amount plagioclase and garnet. In the third unit, biotite shows textures typical of dendritic growth (bifurcating, radiating or branching structures, skeletal core). Plagioclase (An≤25) occurs as small euhedral to subhedral grains scattered in the matrix or forming glomerophyric aggregates. K-feldspar (Or74--100) mostly forms an almost equilibrated mosaic of anhedral perthitic crystals; it also appears in association with albite as a secondary phase replacing plagioclase. The crystallization sequence started with garnet, then proceeded with quartz, plagioclase, biotite and K-feldspar, ended with cordierite, and was followed by subsolidus reequilibration.The variability in size and morphology of quartz and biotite is interpreted in terms of variable undercooling depending on temperature of the host-rocks and on more or less intense degassing of magma batches with variable melt water content. Here, rapid crystallization prevented significant textural reequilibration and allowed the initial crystallization textures of quartz to be preserved. Overall, this study shows that behind the common textquotelefttextquoteleftcoarse-grainedtextquoterighttextquoteright texture of quartz in granite, subsist primary disequilibrium crystallization textures.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We describe a case of S-type alkali-feldspar granite (quartz/K-feldspar/plagioclase/ biotite/garnet �`u 30/35/20/13/2 vol%) showing skeletal and dendritic textures. It consists of three nested units distinguishable by the size of biotite crystals: a first-emplaced unit characterized by small biotite flakes (0.4--9 mm); a second unit with cm-sized biotite platelets (0.3--28 mm) outlining a syn-magmatic foliation; and a third unit formed of large biotite plates (0.7--850 mm) showing dendritic and radial growth patterns.Quartz occurs mostly as rounded to euhedral grains, but also shows complex shapes (serrated outline, re-entrants, etc.). Cathodoluminescence imaging reveals that grains consist of both rounded and skeletal bluish cores (quartz-1) rimmed by reddish overgrowths (quartz-2) that lead locally to the coalescence of neighbouring grains and equilibrated texture. Biotite is poikilitic enclosing dominantly quartz grains but also in lesser amount plagioclase and garnet. In the third unit, biotite shows textures typical of dendritic growth (bifurcating, radiating or branching structures, skeletal core). Plagioclase (An≤25) occurs as small euhedral to subhedral grains scattered in the matrix or forming glomerophyric aggregates. K-feldspar (Or74--100) mostly forms an almost equilibrated mosaic of anhedral perthitic crystals; it also appears in association with albite as a secondary phase replacing plagioclase. The crystallization sequence started with garnet, then proceeded with quartz, plagioclase, biotite and K-feldspar, ended with cordierite, and was followed by subsolidus reequilibration.The variability in size and morphology of quartz and biotite is interpreted in terms of variable undercooling depending on temperature of the host-rocks and on more or less intense degassing of magma batches with variable melt water content. Here, rapid crystallization prevented significant textural reequilibration and allowed the initial crystallization textures of quartz to be preserved. Overall, this study shows that behind the common textquotelefttextquoteleftcoarse-grainedtextquoterighttextquoteright texture of quartz in granite, subsist primary disequilibrium crystallization textures. |
Laumonier, M., Laporte, D., Faure, F., Provost, A., Schiano, P., Ito, K. An experimental study of dissolution and precipitation of forsterite in a thermal gradient: implications for cellular growth of olivine phenocrysts in basalt and melt inclusion formation (Article de journal) Dans: Contributions to Mineralogy and Petrology, vol. 174, p. 94, 2019. @article{Laumonier_etal2019,
title = {An experimental study of dissolution and precipitation of forsterite in a thermal gradient: implications for cellular growth of olivine phenocrysts in basalt and melt inclusion formation},
author = {M. Laumonier and D. Laporte and F. Faure and A. Provost and P. Schiano and K. Ito},
doi = {10.1007/s00410-019-1627-x},
year = {2019},
date = {2019-01-01},
journal = {Contributions to Mineralogy and Petrology},
volume = {174},
pages = {94},
abstract = {The morphology of crystals in magmas strongly depends on the temperature regime of the system, in particular the degree of undercooling and the cooling rate. To simulate low degrees of undercooling, we developed a new experimental setup basedon thermal migration, in which large cylinders of forsterite (single crystals) immersed in haplobasaltic melt were subjected to a temperature gradient. As forsterite solubility is sensitive to temperature, the forsterite on the high-temperature side undergoes dissolution and the dissolved components are transported toward the low-temperature side where a layer of newly grown forsterite forms (up to 340 $mu$m thick after 101 h). A striking feature is that the precipitation process does not produce a planar front of forsterite advancing at the expense of liquid: the growth front shows a fingered outline in planar section, with solid lobes separated by glass tubes that are perpendicular to the growth front. We ascribe this texture to cellular growth, a type of growth that had not been experimentally produced so far in silicate systems. We find that the development of cellulargrowth requires low degrees of undercooling (a few textdegreeC) and large crystal--liquid interfaces (textasciitilde 1 mm across or more), and that it occurs at a growth rate of the order of 10−9 m/s. We found natural occurrences of cellular growth on the rims ofolivines from basanites, but otherwise cellular textures are poorly documented in natural volcanic rocks. Melt inclusions were produced in our experiments, showing that they can form in olivine at relatively slow rates of growth (10−9 m/s or lower).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The morphology of crystals in magmas strongly depends on the temperature regime of the system, in particular the degree of undercooling and the cooling rate. To simulate low degrees of undercooling, we developed a new experimental setup basedon thermal migration, in which large cylinders of forsterite (single crystals) immersed in haplobasaltic melt were subjected to a temperature gradient. As forsterite solubility is sensitive to temperature, the forsterite on the high-temperature side undergoes dissolution and the dissolved components are transported toward the low-temperature side where a layer of newly grown forsterite forms (up to 340 $mu$m thick after 101 h). A striking feature is that the precipitation process does not produce a planar front of forsterite advancing at the expense of liquid: the growth front shows a fingered outline in planar section, with solid lobes separated by glass tubes that are perpendicular to the growth front. We ascribe this texture to cellular growth, a type of growth that had not been experimentally produced so far in silicate systems. We find that the development of cellulargrowth requires low degrees of undercooling (a few textdegreeC) and large crystal--liquid interfaces (textasciitilde 1 mm across or more), and that it occurs at a growth rate of the order of 10−9 m/s. We found natural occurrences of cellular growth on the rims ofolivines from basanites, but otherwise cellular textures are poorly documented in natural volcanic rocks. Melt inclusions were produced in our experiments, showing that they can form in olivine at relatively slow rates of growth (10−9 m/s or lower). |
Vacher, L. G., Truche, L., Faure, F., Tissandier, L., Mosser-Ruck, R., Marrocchi, Y. Deciphering the conditions of tochilinite and cronstedtite formation in CM chondrites from low temperature hydrothermal experiments (Article de journal) Dans: Meteoritics & Planetary Science, vol. 54, p. 1870–1889, 2019. @article{Vacher_etal2019_2,
title = {Deciphering the conditions of tochilinite and cronstedtite formation in CM chondrites from low temperature hydrothermal experiments},
author = {L. G. Vacher and L. Truche and F. Faure and L. Tissandier and R. Mosser-Ruck and Y. Marrocchi},
doi = {10.1111/maps.13317},
year = {2019},
date = {2019-01-01},
journal = {Meteoritics \& Planetary Science},
volume = {54},
pages = {1870--1889},
abstract = {Tochilinite/cronstedtite intergrowths are commonly observed as alteration products in CM chondrite matrices, but the conditions under which they formed are still largely underconstrained due to their scarcity in terrestrial environments. Here, we report low temperature (80 textdegreeC) anoxic hydrothermal experiments using starting assemblages similar to the constituents of the matrices of the most pristine CM chondrite and S-rich and S-free fluids. Cronstedtite crystals formed only in S-free experiments under circumneutral conditions with the highest Fe/Si ratios. Fe-rich tochilinite with chemical and structural characteristics similar to chondritic tochilinite was observed in S-bearing experiments. We observed a positive correlation between the Mg content in the hydroxide layer of synthetic tochilinite and temperature, suggesting that the composition of tochilinite is a proxy for the alteration temperature in CM chondrites. Using this relation, we estimate the mean precipitation temperatures of tochilinite to be 120--160 textdegreeC for CM chondrites. Given the different temperature ranges of tochilinite and cronstedtite in our experiments, we propose that Fe-rich tochilinite crystals resulted from the alteration of metal beads under S-bearing alkaline conditions at T = 120--160 textdegreeC followed by cronstedtite crystals formed by the reaction of matrix amorphous silicates, metal beads, and water at a low temperature (50--120 textdegreeC).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Tochilinite/cronstedtite intergrowths are commonly observed as alteration products in CM chondrite matrices, but the conditions under which they formed are still largely underconstrained due to their scarcity in terrestrial environments. Here, we report low temperature (80 textdegreeC) anoxic hydrothermal experiments using starting assemblages similar to the constituents of the matrices of the most pristine CM chondrite and S-rich and S-free fluids. Cronstedtite crystals formed only in S-free experiments under circumneutral conditions with the highest Fe/Si ratios. Fe-rich tochilinite with chemical and structural characteristics similar to chondritic tochilinite was observed in S-bearing experiments. We observed a positive correlation between the Mg content in the hydroxide layer of synthetic tochilinite and temperature, suggesting that the composition of tochilinite is a proxy for the alteration temperature in CM chondrites. Using this relation, we estimate the mean precipitation temperatures of tochilinite to be 120--160 textdegreeC for CM chondrites. Given the different temperature ranges of tochilinite and cronstedtite in our experiments, we propose that Fe-rich tochilinite crystals resulted from the alteration of metal beads under S-bearing alkaline conditions at T = 120--160 textdegreeC followed by cronstedtite crystals formed by the reaction of matrix amorphous silicates, metal beads, and water at a low temperature (50--120 textdegreeC). |
2018
|
Florentin, L., Deloule, E., Faure, F., Mangin, D. Chemical 3D-imaging of glass inclusions from allende (CV3) olivine via SIMS: A new insight on chondrule formation conditions (Article de journal) Dans: Geochimica et Cosmochimica Acta, vol. 230, p. 83–93, 2018. @article{Florentin_etal2018,
title = {Chemical 3D-imaging of glass inclusions from allende (CV3) olivine via SIMS: A new insight on chondrule formation conditions},
author = {L. Florentin and E. Deloule and F. Faure and D. Mangin},
doi = {10.1016/j.gca.2018.03.021},
year = {2018},
date = {2018-01-01},
journal = {Geochimica et Cosmochimica Acta},
volume = {230},
pages = {83--93},
abstract = {Natural glass inclusions ?\u{I} hosted in Mg-rich olivines from Allende (CV3) type I chondrules ?\u{I} and synthetic melt inclusions ?\u{I} trapped in forsterite crystallized from CMAS (CaO-MgO-Al2O3-SiO2) melts ?\u{I} were mapped by Secondary Ion Mass Spectrometry(SIMS) for CMAS major oxides. The first ever 3D chemical images of extra-terrestrial glass inclusions were obtained, along with chemical depth profiles for each oxide. Results show similar patterns for both synthetic glass inclusions (trapped in olivine formed by slow crystallization in a magmatic liquid) and natural inclusions from Allendetextquoterights olivines. No incompatible-rich boundary layer or diffusion pattern was observed in either case. The absence of anincompatible-rich boundary layer suggests that the olivine overgrowth surrounding glass inclusions in Allendetextquoterights olivines was formed during slow cooling of the host olivine and likely the surrounding chondrule. This provides new constraints on the cooling rates of type I chondrules.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Natural glass inclusions ?Ĭ hosted in Mg-rich olivines from Allende (CV3) type I chondrules ?Ĭ and synthetic melt inclusions ?Ĭ trapped in forsterite crystallized from CMAS (CaO-MgO-Al2O3-SiO2) melts ?Ĭ were mapped by Secondary Ion Mass Spectrometry(SIMS) for CMAS major oxides. The first ever 3D chemical images of extra-terrestrial glass inclusions were obtained, along with chemical depth profiles for each oxide. Results show similar patterns for both synthetic glass inclusions (trapped in olivine formed by slow crystallization in a magmatic liquid) and natural inclusions from Allendetextquoterights olivines. No incompatible-rich boundary layer or diffusion pattern was observed in either case. The absence of anincompatible-rich boundary layer suggests that the olivine overgrowth surrounding glass inclusions in Allendetextquoterights olivines was formed during slow cooling of the host olivine and likely the surrounding chondrule. This provides new constraints on the cooling rates of type I chondrules. |
Fournier, J., Régnier, E., Faure, F., Goff, X. Le, Brau, H. P., Brackx, E., Pinet, O. Modeling of dissolution kinetics of rare earth crystals in a borosilicate glass melt (Article de journal) Dans: Journal of Non-Crystalline Solids, vol. 481, p. 248–253, 2018. @article{Fournier_etal2018,
title = {Modeling of dissolution kinetics of rare earth crystals in a borosilicate glass melt},
author = {J. Fournier and E. R\'{e}gnier and F. Faure and X. Le Goff and H. P. Brau and E. Brackx and O. Pinet},
doi = {http://d10.1016/j.jnoncrysol.2017.10.042},
year = {2018},
date = {2018-01-01},
journal = {Journal of Non-Crystalline Solids},
volume = {481},
pages = {248--253},
abstract = {The novelty of this work is the comparison of two methods to determine the dissolution kinetics in order to evaluate the applicability of the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model for the crystals dissolution in silicate melts. For this, this work focuses on the dissolution of rare earth (RE) silicates (Ca2RE8(SiO4)6O2 where RE =Nd) with an apatite structure in a sodium-borosilicate glass melt. The first approach consists in the characterization of the dissolution kinetics by following the crystalline area fraction by image analysis as afunction of time and temperature. Then, a model based on the generalized JMAK equation is proposed to fit the experimental data. This model enables to determine both the mechanism limiting the dissolution (i.e. the diffusion) and the activation energy of crystals dissolution in the studied glass system (496 kJ/mol). To supportthese results, a second and most common approach is the measure of the chemical profiles at the crystal/melt interfaces by microprobe. The conclusions obtained by this last method are in agreement with the conclusions based on JMAK model. All these results allowed to confirm that the JMAK model is well suited to model crystals dissolution in silicate melts.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The novelty of this work is the comparison of two methods to determine the dissolution kinetics in order to evaluate the applicability of the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model for the crystals dissolution in silicate melts. For this, this work focuses on the dissolution of rare earth (RE) silicates (Ca2RE8(SiO4)6O2 where RE =Nd) with an apatite structure in a sodium-borosilicate glass melt. The first approach consists in the characterization of the dissolution kinetics by following the crystalline area fraction by image analysis as afunction of time and temperature. Then, a model based on the generalized JMAK equation is proposed to fit the experimental data. This model enables to determine both the mechanism limiting the dissolution (i.e. the diffusion) and the activation energy of crystals dissolution in the studied glass system (496 kJ/mol). To supportthese results, a second and most common approach is the measure of the chemical profiles at the crystal/melt interfaces by microprobe. The conclusions obtained by this last method are in agreement with the conclusions based on JMAK model. All these results allowed to confirm that the JMAK model is well suited to model crystals dissolution in silicate melts. |
Fournier, J., Régnier, E., Faure, F., Goff, X. Le, Brau, H. P., Brackx, E., Pinet, O. Application of the JMAK model for crystal dissolution kinetics in a borosilicate melt (Article de journal) Dans: Journal of Non-Crystalline Solids, vol. 489, p. 77–83, 2018. @article{Fournier_etal2018_2,
title = {Application of the JMAK model for crystal dissolution kinetics in a borosilicate melt},
author = {J. Fournier and E. R\'{e}gnier and F. Faure and X. Le Goff and H. P. Brau and E. Brackx and O. Pinet},
doi = {10.1016/j.jnoncrysol.2018.03.018},
year = {2018},
date = {2018-01-01},
journal = {Journal of Non-Crystalline Solids},
volume = {489},
pages = {77--83},
abstract = {In the literature, a previous work has validated the application of the generalized JMAK equation to model the crystal dissolution kinetics in silicate melts for T \> Tliq. Because this dissolution can happen at temperatures below Tliq, the purpose of this work was to test this model for T \< Tliq. To do so, the dissolution kinetics of rare earth (RE) silicate in a borosilicate melt were studied by following (with image analysis) the evolution of the crystal fraction as a function of time and temperature. The application of the model enables the mechanismlimiting the dissolution to be known, i.e. the diffusion and the activation energy of the dissolution (475 kJ/mol). These conclusions are the same as those resulting from the application for T \> Tliq. This shows the continuity of the dissolution around Tliq which is, in addition, confirmed by the chemical profile study performed by microprobe analysis. Moreover, it validates the application of the JMAK model for crystal dissolution whatever the temperature. Furthermore, the study of the crystal morphologies during dissolution indicates that a mechanism called textquotelefttextquoteleftcrystal attack/splittingtextquoterighttextquoteright occurs for T \> Tliq and leads to a change in value of the Avrami exponent.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In the literature, a previous work has validated the application of the generalized JMAK equation to model the crystal dissolution kinetics in silicate melts for T > Tliq. Because this dissolution can happen at temperatures below Tliq, the purpose of this work was to test this model for T < Tliq. To do so, the dissolution kinetics of rare earth (RE) silicate in a borosilicate melt were studied by following (with image analysis) the evolution of the crystal fraction as a function of time and temperature. The application of the model enables the mechanismlimiting the dissolution to be known, i.e. the diffusion and the activation energy of the dissolution (475 kJ/mol). These conclusions are the same as those resulting from the application for T > Tliq. This shows the continuity of the dissolution around Tliq which is, in addition, confirmed by the chemical profile study performed by microprobe analysis. Moreover, it validates the application of the JMAK model for crystal dissolution whatever the temperature. Furthermore, the study of the crystal morphologies during dissolution indicates that a mechanism called textquotelefttextquoteleftcrystal attack/splittingtextquoterighttextquoteright occurs for T > Tliq and leads to a change in value of the Avrami exponent. |
2017
|
Faure, F., Tissandier, L., Florentin, L., Devineau, K. A magmatic origin for silica-rich glass inclusions hosted in porphyritic magnesian olivines in chondrules: An experimental study (Article de journal) Dans: Geochimica et Cosmochimica Acta, vol. 204, p. 19–31, 2017. @article{Faure_etal2017,
title = {A magmatic origin for silica-rich glass inclusions hosted in porphyritic magnesian olivines in chondrules: An experimental study},
author = {F. Faure and L. Tissandier and L. Florentin and K. Devineau},
doi = {10.1016/j.gca.2017.01.034},
year = {2017},
date = {2017-01-01},
journal = {Geochimica et Cosmochimica Acta},
volume = {204},
pages = {19--31},
abstract = {Rare silica-rich glass inclusions (69 \< SiO2 \< 82 wt.%) are described within magnesian olivines of porphyritic Type IA chondrules. These glass inclusion compositions are clearly out of equilibrium with their host Mg-olivines and their presence within the olivines is generally attributed to an unclear secondary process such as a late interaction with nebular gases. We performed dynamic crystallisation experiments that demonstrate that these Si-rich glass inclusions are actually magmatic in origin and were trapped inside olivines that crystallized slowly from a magma with a CI, i.e. solar, composition. Their silicarichcompositions are the consequence of the small volumes of inclusions, which inhibit the nucleation of secondary crystalline phase (Ca-poor pyroxene) but allow olivine to continue to crystallize metastably on the walls of the inclusions. We suggestthat Si-rich glass inclusions could be the only reliable relicts of what were the first magmas of the solar system, exhibiting a CI, i.e. non-fractionated, composition.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Rare silica-rich glass inclusions (69 < SiO2 < 82 wt.%) are described within magnesian olivines of porphyritic Type IA chondrules. These glass inclusion compositions are clearly out of equilibrium with their host Mg-olivines and their presence within the olivines is generally attributed to an unclear secondary process such as a late interaction with nebular gases. We performed dynamic crystallisation experiments that demonstrate that these Si-rich glass inclusions are actually magmatic in origin and were trapped inside olivines that crystallized slowly from a magma with a CI, i.e. solar, composition. Their silicarichcompositions are the consequence of the small volumes of inclusions, which inhibit the nucleation of secondary crystalline phase (Ca-poor pyroxene) but allow olivine to continue to crystallize metastably on the walls of the inclusions. We suggestthat Si-rich glass inclusions could be the only reliable relicts of what were the first magmas of the solar system, exhibiting a CI, i.e. non-fractionated, composition. |
Florentin, L., Faure, F., Deloule, E., Tissandier, L., Gurenko, A., Lequin, D. Origin of Na in glass inclusions hosted in olivine from Allende CV3 and Jbilet Winselwan CM2: Implications for chondrule formation (Article de journal) Dans: Earth and Planetary Science Letters, vol. 474, p. 160–171, 2017. @article{Florentin_etal2017,
title = {Origin of Na in glass inclusions hosted in olivine from Allende CV3 and Jbilet Winselwan CM2: Implications for chondrule formation},
author = {L. Florentin and F. Faure and E. Deloule and L. Tissandier and A. Gurenko and D. Lequin},
doi = {10.1016/j.epsl.2017.06.038},
year = {2017},
date = {2017-01-01},
journal = {Earth and Planetary Science Letters},
volume = {474},
pages = {160--171},
abstract = {Glass inclusions trapped in Mg-rich olivines within type I chondrules from the Allende (CV3) and Jbilet Winselwan (CM2) chondrites were analyzed by EPMA (Electron Probe Microanalysis) for major elements and by SIMS (Secondary Ion Mass Spectrometry) for Cl and S (analyzed here for the first time in chondrule-hosted glass inclusions). The inclusions from Jbilet Winselwan are poor in Na2O, whereas those from Allende are Na-rich, displaying up to 8wt.% Na2O. The source of Na is a central issue in terms of chondrule origins because of the volatility of Na at high temperature. The wide scatter in Na2O contents of olivine-hosted glass inclusions from chondrules has led the community to propose that Na2O came from late interactions of chondrules with a Si/Na-rich gas. To gain new insights into the origins of the Na2O recorded in glass inclusions, heating experiments (up to 1810◦C) were performed on Allende inclusions in an effort to constrain the initial composition of the trapped melts. Our results demonstrate that sodium (although volatile) does not escape from inclusions during heating, thus confirming that glass inclusions behave as closed systems. Furthermore, heated olivines still bear inclusions containing up to 7.2wt.% of Na2O. Olivines are thought to form at temperatures at which Na is volatile. This implies that (1) Na from glass inclusions cannot come from condensation but rather results from trapping in a Na-rich environment, which implies a high pressure, as in a melting planetasimal (2) there may be two distinct origins for the sodium: an indigenous origin for the sodium trapped inside glass inclusions and a gaseous origin for the sodium recorded in mesostasis from chondrules. Consequently, these results are in favor of a planetesimal origin for olivine from chondrules.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Glass inclusions trapped in Mg-rich olivines within type I chondrules from the Allende (CV3) and Jbilet Winselwan (CM2) chondrites were analyzed by EPMA (Electron Probe Microanalysis) for major elements and by SIMS (Secondary Ion Mass Spectrometry) for Cl and S (analyzed here for the first time in chondrule-hosted glass inclusions). The inclusions from Jbilet Winselwan are poor in Na2O, whereas those from Allende are Na-rich, displaying up to 8wt.% Na2O. The source of Na is a central issue in terms of chondrule origins because of the volatility of Na at high temperature. The wide scatter in Na2O contents of olivine-hosted glass inclusions from chondrules has led the community to propose that Na2O came from late interactions of chondrules with a Si/Na-rich gas. To gain new insights into the origins of the Na2O recorded in glass inclusions, heating experiments (up to 1810◦C) were performed on Allende inclusions in an effort to constrain the initial composition of the trapped melts. Our results demonstrate that sodium (although volatile) does not escape from inclusions during heating, thus confirming that glass inclusions behave as closed systems. Furthermore, heated olivines still bear inclusions containing up to 7.2wt.% of Na2O. Olivines are thought to form at temperatures at which Na is volatile. This implies that (1) Na from glass inclusions cannot come from condensation but rather results from trapping in a Na-rich environment, which implies a high pressure, as in a melting planetasimal (2) there may be two distinct origins for the sodium: an indigenous origin for the sodium trapped inside glass inclusions and a gaseous origin for the sodium recorded in mesostasis from chondrules. Consequently, these results are in favor of a planetesimal origin for olivine from chondrules. |
Tissandier, L., Florentin, L., Lequin, D., Baillot, P., Faure, F. A new heating stage for high temperature/low fO2 conditions (Article de journal) Dans: Journal of Crystal Growth, vol. 458, p. 72–79, 2017. @article{Tissandier_etal2017,
title = {A new heating stage for high temperature/low fO2 conditions},
author = {L. Tissandier and L. Florentin and D. Lequin and P. Baillot and F. Faure},
doi = {10.1016/j.jcrysgro.2016.11.043},
year = {2017},
date = {2017-01-01},
journal = {Journal of Crystal Growth},
volume = {458},
pages = {72--79},
abstract = {Understanding the processes involved in the formation of intracrystalline inclusions can be valuable for both geological studies and industrial production. In view of this, we developed a new heating stage that can operate in extreme conditions. The use of tungsten as the heating material allows temperatures of over 2000 textdegreeC to be reached and also requires that experiments are run under reducing atmospheres. Small samples of metal are needed to calibrate the temperature for each experiment and the fO2 is achieved by a flow of mixed gases (CO, Ar, He). The first experiments run on this device highlight the good agreement between the different ways of estimating the temperature (by the amount of power delivered, the use of a thermocouple or by chemical composition), and a precision of textpm 20 textdegreeC is obtained for temperature determinations. As well as the homogenization of magmatic inclusions in ultramafic rocks, processes such as whisker crystal formation or transcrystalline migration of inclusions can be investigated using the new stage thanks to its very high maximum temperature and to the thermal gradients observed close to the heating wires. This new device looks to be a very promising tool that could easily be adapted for a range of studies by changing the nature and shape of the heating filaments.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Understanding the processes involved in the formation of intracrystalline inclusions can be valuable for both geological studies and industrial production. In view of this, we developed a new heating stage that can operate in extreme conditions. The use of tungsten as the heating material allows temperatures of over 2000 textdegreeC to be reached and also requires that experiments are run under reducing atmospheres. Small samples of metal are needed to calibrate the temperature for each experiment and the fO2 is achieved by a flow of mixed gases (CO, Ar, He). The first experiments run on this device highlight the good agreement between the different ways of estimating the temperature (by the amount of power delivered, the use of a thermocouple or by chemical composition), and a precision of textpm 20 textdegreeC is obtained for temperature determinations. As well as the homogenization of magmatic inclusions in ultramafic rocks, processes such as whisker crystal formation or transcrystalline migration of inclusions can be investigated using the new stage thanks to its very high maximum temperature and to the thermal gradients observed close to the heating wires. This new device looks to be a very promising tool that could easily be adapted for a range of studies by changing the nature and shape of the heating filaments. |
2016
|
Pignatelli, I., Faure, F., Mosser-Ruck, R. Self-mixing magma in the Ruiz Peak rhyodacite (New Mexico, USA): A mechanism explaining the formation of long period polytypes of mica (Article de journal) Dans: Lithos, vol. 266-267, p. 332–347, 2016. @article{Pignatelli_etal2016,
title = {Self-mixing magma in the Ruiz Peak rhyodacite (New Mexico, USA): A mechanism explaining the formation of long period polytypes of mica},
author = {I. Pignatelli and F. Faure and R. Mosser-Ruck},
doi = {10.1016/j.lithos.2016.10.024},
year = {2016},
date = {2016-01-01},
journal = {Lithos},
volume = {266-267},
pages = {332--347},
abstract = {The rhyodacite of Ruiz Peak Volcano (New Mexico, USA) is an exceptional rock because it contains both long period and short period polytypes of mica. Our petrographic study shows that this rhyodacite is characterized by numerous disequilibrium textures of phenocrysts (mica, amphibole, clinopyroxene, olivine and plagioclase) contained within both dark-grey and reddish coloured groundmass. The presence of two groundmasses, as well as of disequilibrium textures (reaction rims, resorption, dendritic, skeletal morphologies, etc.) suggests a complex magmatic history. These two types of groundmass are not due to a mixing of magmas but result from a degassing process during the magma ascent in the conduit. The disequilibrium textures are interpreted to be the result of small, short-lived convection cells in the magmatic chamber, which may allow crystal-crystal,crystal-spiral and spiral-spiral interactions to occur, leading to the formation of long period polytypes of mica. For the first time, the relationships between the crystallographic features of mica and the host-rock formation are underlined in this study. It follows that long period polytypes of mica can be considered markers of the complex history of magmas.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The rhyodacite of Ruiz Peak Volcano (New Mexico, USA) is an exceptional rock because it contains both long period and short period polytypes of mica. Our petrographic study shows that this rhyodacite is characterized by numerous disequilibrium textures of phenocrysts (mica, amphibole, clinopyroxene, olivine and plagioclase) contained within both dark-grey and reddish coloured groundmass. The presence of two groundmasses, as well as of disequilibrium textures (reaction rims, resorption, dendritic, skeletal morphologies, etc.) suggests a complex magmatic history. These two types of groundmass are not due to a mixing of magmas but result from a degassing process during the magma ascent in the conduit. The disequilibrium textures are interpreted to be the result of small, short-lived convection cells in the magmatic chamber, which may allow crystal-crystal,crystal-spiral and spiral-spiral interactions to occur, leading to the formation of long period polytypes of mica. For the first time, the relationships between the crystallographic features of mica and the host-rock formation are underlined in this study. It follows that long period polytypes of mica can be considered markers of the complex history of magmas. |
2014
|
Borisova, A. Y., Faure, F., Deloule, E., Grégoire, M., Béjina, F., Parseval, P., Devidal, J. L. Lead isotope signatures of Kerguelen plume-derived olivine-hosted melt inclusions: Constraints on the ocean island basalt petrogenesis (Article de journal) Dans: Lithos, vol. 198-199, p. 153–171, 2014. @article{Borisova_etal2014,
title = {Lead isotope signatures of Kerguelen plume-derived olivine-hosted melt inclusions: Constraints on the ocean island basalt petrogenesis},
author = {A. Y. Borisova and F. Faure and E. Deloule and M. Gr\'{e}goire and F. B\'{e}jina and P. Parseval and J. L. Devidal},
doi = {10.1016/j.lithos.2014.03.022 0024-4937},
year = {2014},
date = {2014-01-01},
journal = {Lithos},
volume = {198-199},
pages = {153--171},
abstract = {The nature of magmatic sources reflected by isotopic composition of the ocean island basalt (OIB) remains an ongoing question in igneous geochemistry. To constrain the magmatic sources for OIB related to the Kerguelen plume activity, we performed detailed microanalytical investigation of the 21.4 Ma picritic basalt (MD109-D6- 87) dredged during the textquotelefttextquoteleftMarion Dufresnetextquoterighttextquoteright cruise on a seamount between Kerguelen Archipelago and Heard Island. Lead isotope compositions of olivine-hosted melt inclusions and matrix glasses were measured by Laser Ablation Multiple Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) and SecondaryIon Mass Spectrometry (SIMS). We also performed major and trace element microanalyses and mapping of the inclusions and the host olivine phenocrysts by electron microprobe (wavelength-dispersive X-ray spectroscopy, WDS). The observed significant major element (K2O/P2O5, Al2O3/TiO2) and Pb isotope (207Pb/206Pband 208Pb/206Pb) heterogeneities of parental melts (MgO=7--10 wt.%) during early high pressure crystallisation stage (200--300MPa, Fo82--86 mol%), and relative homogeneity at later lower-pressure crystallisation stage (b100 MPa, Fo75--80 mol%) are interpreted by mixing between textquotelefttextquoteleftPlumetextquoterighttextquoteright and textquotelefttextquoteleftAssimilanttextquoterighttextquoteright melts during magma residence and transport. Lead isotope composition of the parental basaltic melts was inherited from both heterogeneous mantle and the Kerguelen Plateau crust. High K2O/P2O5 (N4), Al2O3/TiO2 (N4) ratios are attributed to assimilation of the plateau basaltic crust (�W50 wt.%) by the melts in the magma chamber at palaeodepths from6 to 9 km. The crustal assimilation may have happened through plagioclase dissolution. The large chemical and isotopic heterogeneityof the parental OIB melts found by in situ microanalyses in this study suggests that the bulk rock chemistry alone cannot provide enough information to constrain the nature of the magmatic sources.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The nature of magmatic sources reflected by isotopic composition of the ocean island basalt (OIB) remains an ongoing question in igneous geochemistry. To constrain the magmatic sources for OIB related to the Kerguelen plume activity, we performed detailed microanalytical investigation of the 21.4 Ma picritic basalt (MD109-D6- 87) dredged during the textquotelefttextquoteleftMarion Dufresnetextquoterighttextquoteright cruise on a seamount between Kerguelen Archipelago and Heard Island. Lead isotope compositions of olivine-hosted melt inclusions and matrix glasses were measured by Laser Ablation Multiple Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) and SecondaryIon Mass Spectrometry (SIMS). We also performed major and trace element microanalyses and mapping of the inclusions and the host olivine phenocrysts by electron microprobe (wavelength-dispersive X-ray spectroscopy, WDS). The observed significant major element (K2O/P2O5, Al2O3/TiO2) and Pb isotope (207Pb/206Pband 208Pb/206Pb) heterogeneities of parental melts (MgO=7--10 wt.%) during early high pressure crystallisation stage (200--300MPa, Fo82--86 mol%), and relative homogeneity at later lower-pressure crystallisation stage (b100 MPa, Fo75--80 mol%) are interpreted by mixing between textquotelefttextquoteleftPlumetextquoterighttextquoteright and textquotelefttextquoteleftAssimilanttextquoterighttextquoteright melts during magma residence and transport. Lead isotope composition of the parental basaltic melts was inherited from both heterogeneous mantle and the Kerguelen Plateau crust. High K2O/P2O5 (N4), Al2O3/TiO2 (N4) ratios are attributed to assimilation of the plateau basaltic crust (�W50 wt.%) by the melts in the magma chamber at palaeodepths from6 to 9 km. The crustal assimilation may have happened through plagioclase dissolution. The large chemical and isotopic heterogeneityof the parental OIB melts found by in situ microanalyses in this study suggests that the bulk rock chemistry alone cannot provide enough information to constrain the nature of the magmatic sources. |
Bouquain, S., Arndt, N. T., Faure, F., Libourel, G. An experimental study of pyroxene crystallization during rapid cooling in a thermal gradient: application to komatiites (Article de journal) Dans: Solid Earth, vol. 5, p. 641–650, 2014. @article{Bouquain_etal2014,
title = {An experimental study of pyroxene crystallization during rapid cooling in a thermal gradient: application to komatiites},
author = {S. Bouquain and N. T. Arndt and F. Faure and G. Libourel},
doi = {doi:10.5194/se-5-641-2014},
year = {2014},
date = {2014-01-01},
journal = {Solid Earth},
volume = {5},
pages = {641--650},
abstract = {Abstract. To investigate the crystallization of pyroxene in spinifex-textured komatiites, we undertook a series of experiments in which compositions in the CaO-MgO-Al2O3-SiO2 CMAS system were cooled rapidly in a thermal gradient. Cooling rates were generally between 5 and 10 C h−1, but some runs were made at 100--200 C h−1; thermal gradients were between 10 and 20 C cm−1. These conditions reproducedthose at various depths in the crust of komatiite lava flow. The starting composition was chosen to have pigeonite on the liquidus, and most of the experimental charges crystallized zoned pigeonite--diopside crystals like those in komatiite lavas. An intriguing aspect of the experimental results was their lack of reproducibility. Some experiments crystallized forsterite, whereas others that were run under similar conditions crystallized two pyroxenes and no forsterite; some experiments were totally glassy, but others crystallized entirely to pyroxene. The degree of supercooling at the onset of pyroxene crystallization was variable, from less than 25 C to more than 110 C. We attribute these results to the difficulty of nucleation of pyroxene under the conditions of the experiments.In some cases forsterite crystallized metastably and modified the liquid composition to inhibit pyroxene crystallization in others no nucleation took place until a large degree of supercooling was achieved, and then pyroxene crystallizedrapidly. Pigeonite crystallized under a wide range of conditions, at cooling rates from 3 to 100 C h−1. The notion that this mineral only forms at low cooling rates is not correct.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abstract. To investigate the crystallization of pyroxene in spinifex-textured komatiites, we undertook a series of experiments in which compositions in the CaO-MgO-Al2O3-SiO2 CMAS system were cooled rapidly in a thermal gradient. Cooling rates were generally between 5 and 10 C h−1, but some runs were made at 100--200 C h−1; thermal gradients were between 10 and 20 C cm−1. These conditions reproducedthose at various depths in the crust of komatiite lava flow. The starting composition was chosen to have pigeonite on the liquidus, and most of the experimental charges crystallized zoned pigeonite--diopside crystals like those in komatiite lavas. An intriguing aspect of the experimental results was their lack of reproducibility. Some experiments crystallized forsterite, whereas others that were run under similar conditions crystallized two pyroxenes and no forsterite; some experiments were totally glassy, but others crystallized entirely to pyroxene. The degree of supercooling at the onset of pyroxene crystallization was variable, from less than 25 C to more than 110 C. We attribute these results to the difficulty of nucleation of pyroxene under the conditions of the experiments.In some cases forsterite crystallized metastably and modified the liquid composition to inhibit pyroxene crystallization in others no nucleation took place until a large degree of supercooling was achieved, and then pyroxene crystallizedrapidly. Pigeonite crystallized under a wide range of conditions, at cooling rates from 3 to 100 C h−1. The notion that this mineral only forms at low cooling rates is not correct. |
Faure, F., Tissandier, L. Contrasted liquid lines of descent revealed by olivine-hosted melt inclusions and the external magma (Article de journal) Dans: Journal of Petrology, vol. 55, no. 9, p. 1779–1798, 2014. @article{Faure+Tissandier2014,
title = {Contrasted liquid lines of descent revealed by olivine-hosted melt inclusions and the external magma},
author = {F. Faure and L. Tissandier},
doi = {To better understand the significance of the chemical compositions of forsterite-hosted melt inclusi},
year = {2014},
date = {2014-01-01},
journal = {Journal of Petrology},
volume = {55},
number = {9},
pages = {1779--1798},
abstract = {To better understand the significance of the chemical compositions of forsterite-hosted melt inclusions, dynamic crystallization experiments were performed at atmospheric pressure and a low cooling rate (28Ch1) on a starting glass material with a composition in the CMAS system (12textperiodcentered21wt % CaO, 28textperiodcentered48 wt % MgO, 11textperiodcentered96 wt % Al2O3,47textperiodcentered32 wt % SiO2). Experiments were quenched at various temperatures, both above and below the theoretical solidus. Olivine is the liquidus phase and the mesostasis may exhibit a second crystalline phase corresponding to a metastable Al-rich pyroxene. Olivine crystal morphologies change from polyhedral to skeletal, depending on the quenching temperature. Regardless of the quenching temperature, the chemical compositions of liquids trapped in melt (now glass) inclusionsin the olivines do not contain the boundary layer that should result from rapid growth of these crystals. The liquid compositions also show that down to temperatures far below the theoretical solidus, olivine is the only phase that crystallizes on the walls of these inclusions. Glass inclusion analyses can therefore be used to determine the chemical evolution of a liquid in metastable equilibrium with the host olivine, irrespective of the quenching temperature. Melt inclusions therefore follow their own liquid line of descent distinct from that of the whole charge. This experimental study suggests that it should be possible to (1) draw the metastable extensions of the liquidus from natural glass inclusions and (2) determine the real supersaturation degrees of the residual magmas.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
To better understand the significance of the chemical compositions of forsterite-hosted melt inclusions, dynamic crystallization experiments were performed at atmospheric pressure and a low cooling rate (28Ch1) on a starting glass material with a composition in the CMAS system (12textperiodcentered21wt % CaO, 28textperiodcentered48 wt % MgO, 11textperiodcentered96 wt % Al2O3,47textperiodcentered32 wt % SiO2). Experiments were quenched at various temperatures, both above and below the theoretical solidus. Olivine is the liquidus phase and the mesostasis may exhibit a second crystalline phase corresponding to a metastable Al-rich pyroxene. Olivine crystal morphologies change from polyhedral to skeletal, depending on the quenching temperature. Regardless of the quenching temperature, the chemical compositions of liquids trapped in melt (now glass) inclusionsin the olivines do not contain the boundary layer that should result from rapid growth of these crystals. The liquid compositions also show that down to temperatures far below the theoretical solidus, olivine is the only phase that crystallizes on the walls of these inclusions. Glass inclusion analyses can therefore be used to determine the chemical evolution of a liquid in metastable equilibrium with the host olivine, irrespective of the quenching temperature. Melt inclusions therefore follow their own liquid line of descent distinct from that of the whole charge. This experimental study suggests that it should be possible to (1) draw the metastable extensions of the liquidus from natural glass inclusions and (2) determine the real supersaturation degrees of the residual magmas. |
2013
|
Marin-Carbonne, J., Faure, F., Chaussidon, M., Jacob, D., Robert, F. A petrographic and isotopic criterion of the state of preservation of Precambrian cherts based on the characterization of the quartz veins (Article de journal) Dans: Precambrian Research, vol. 231, p. 290–300, 2013. @article{Marin-Carbonne_etal2013,
title = {A petrographic and isotopic criterion of the state of preservation of Precambrian cherts based on the characterization of the quartz veins},
author = {J. Marin-Carbonne and F. Faure and M. Chaussidon and D. Jacob and F. Robert},
doi = {10.1016/j.precamres.2013.03.019},
year = {2013},
date = {2013-01-01},
journal = {Precambrian Research},
volume = {231},
pages = {290--300},
abstract = {The coupled O and Si isotope variations of Precambrian cherts show secular and correlated variations that have been interpreted as a progressive cooling of the oceans on Earth. However, this reconstruction has been challenged because cherts can have various origins (hydrothermal, sedimentary, volcanic silicification) and their isotopic compositions might have been reset by metamorphic fluid circulation. Evenpristine samples show evidence of fluid circulation by the presence of various quartz veins. Here, we have determined the effect of fluid circulation on the isotopic composition of the microquartz chert matrix by studying the mineralogical relationships between quartz veins and microquartz in two distinctive chert samples. These samples show different quartz habit and texture in their quartz veins, which imply various fluid system conditions. Therefore the presence of quartz spherulites in the quartz veins indicatesa more moderate fluid circulation than the presence of columnar quartz. These observations were also confirmed by the oxygen isotope compositions of both microquartz matrix chert and quartz veins. We have demonstrated that in some conditions, fluid circulations do not modify the oxygen isotope composition of the chert matrix and thus the microquartz can still record paleo-environmental conditions. The petrography of quartz vein associated with in situ oxygen isotope composition provides one criterion to characterize the state of preservation of the microquartz.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The coupled O and Si isotope variations of Precambrian cherts show secular and correlated variations that have been interpreted as a progressive cooling of the oceans on Earth. However, this reconstruction has been challenged because cherts can have various origins (hydrothermal, sedimentary, volcanic silicification) and their isotopic compositions might have been reset by metamorphic fluid circulation. Evenpristine samples show evidence of fluid circulation by the presence of various quartz veins. Here, we have determined the effect of fluid circulation on the isotopic composition of the microquartz chert matrix by studying the mineralogical relationships between quartz veins and microquartz in two distinctive chert samples. These samples show different quartz habit and texture in their quartz veins, which imply various fluid system conditions. Therefore the presence of quartz spherulites in the quartz veins indicatesa more moderate fluid circulation than the presence of columnar quartz. These observations were also confirmed by the oxygen isotope compositions of both microquartz matrix chert and quartz veins. We have demonstrated that in some conditions, fluid circulations do not modify the oxygen isotope composition of the chert matrix and thus the microquartz can still record paleo-environmental conditions. The petrography of quartz vein associated with in situ oxygen isotope composition provides one criterion to characterize the state of preservation of the microquartz. |
Seddiki, A., Moine, B., Cottin, J. Y., Bascou, J., Godard, M., Faure, F., Bourot-Denise, M., Remaci, N. A mineralogical and geochemical study of polymict eucrite discovered in Sahara of southwest Algeria (Article de journal) Dans: Arabian Journal of Geosciences, vol. 6, no. 9, p. 3175–3184, 2013. @article{Seddiki_etal2013,
title = {A mineralogical and geochemical study of polymict eucrite discovered in Sahara of southwest Algeria},
author = {A. Seddiki and B. Moine and J. Y. Cottin and J. Bascou and M. Godard and F. Faure and M. Bourot-Denise and N. Remaci},
doi = {10.1007/s12517-012-0624-4},
year = {2013},
date = {2013-01-01},
journal = {Arabian Journal of Geosciences},
volume = {6},
number = {9},
pages = {3175--3184},
abstract = {NWA2268 is a polymict eucrite discovered in the Sahara, at southwest Algeria, close to the region of Tindouf. This meteorite weighs 65 g and presents a thin black fusion crust. The rock is fine- to medium-grained breccia and contains mineral fragments of plagioclases, pyroxenes, spinel, olivine and silica. The rock contains some basaltic fragments with sub-ophitic or cumulative textures, constituted by plagioclases and exsolved pigeonite. Pyroxferroitegrains are present and locally destabilised in an association of hedenbergite, fayalite and silica. It also presents unequilibrated eucritic clast with heterogeneous pyroxenes and plagioclases compositions. Pyroxenes in the all of the other clasts have equilibrated composition, with exolved pigeoniteswith augite lamellaes. This polymict eucrite contains also partially devitrified glass that represents impact melts linked to impact event. None recrystallization of this glass confirms a lack of post-brecciation metamorphism. Diogenitic fragments are less abundant than 10 %. The oxygen isotopic composition of NWA2268 is $Delta$17O (−0.43). This meteorite is interpreted as belonging to the HED group attributed to the 4-Vesta asteroid.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
NWA2268 is a polymict eucrite discovered in the Sahara, at southwest Algeria, close to the region of Tindouf. This meteorite weighs 65 g and presents a thin black fusion crust. The rock is fine- to medium-grained breccia and contains mineral fragments of plagioclases, pyroxenes, spinel, olivine and silica. The rock contains some basaltic fragments with sub-ophitic or cumulative textures, constituted by plagioclases and exsolved pigeonite. Pyroxferroitegrains are present and locally destabilised in an association of hedenbergite, fayalite and silica. It also presents unequilibrated eucritic clast with heterogeneous pyroxenes and plagioclases compositions. Pyroxenes in the all of the other clasts have equilibrated composition, with exolved pigeoniteswith augite lamellaes. This polymict eucrite contains also partially devitrified glass that represents impact melts linked to impact event. None recrystallization of this glass confirms a lack of post-brecciation metamorphism. Diogenitic fragments are less abundant than 10 %. The oxygen isotopic composition of NWA2268 is $Delta$17O (−0.43). This meteorite is interpreted as belonging to the HED group attributed to the 4-Vesta asteroid. |
Welsch, B., Faure, F., Famin, V., Baronnet, A., Bach`elery, P. Dentritic crystallization: A single process for all the textures of olivine in basalts? (Article de journal) Dans: Journal of Petrology, vol. 54, no. 3, p. 539–574, 2013. @article{Welsch_etal2013,
title = {Dentritic crystallization: A single process for all the textures of olivine in basalts?},
author = {B. Welsch and F. Faure and V. Famin and A. Baronnet and P. Bach`elery},
doi = {10.1093/petrology/egs077},
year = {2013},
date = {2013-01-01},
journal = {Journal of Petrology},
volume = {54},
number = {3},
pages = {539--574},
abstract = {The olivine macrocrysts found in oceanites, picrites and magnesian basalts erupted at hotspot volcanoes are generally interpreted either as phenocrysts crystallized from the magma or as xenocrysts extracted from a deforming cumulate.To constrain the origin of these crystals we studied their texture and composition at Piton de la Fournaise volcano, La Reunion.We show that macrocrysts are organized andsubdivided into parallel units; this suggests a crystallization by dendriticgrowth and ripening rather than by a complex combination of paired nucleation, crystal aggregation or synneusis. Dendritic growth is also evidenced by the occurrence of hollow faces, P-rich zones, melt and Cr-spinel inclusions formed from the accumulation of slow diffusing impurities (P, Cr, Al) in the liquid at the contact with rapid-growing olivine.We suggest that early dendritic crystallization may even cause branch misorientations and lattice mismatches,yielding subgrain boundaries, dislocation lamellae and to a certain extent undulose extinction, which have all been formerly interpreted in terms of plastic intracrystalline deformation.We interpret olivine macrocrysts as phenocrysts crystallized under a strong degree of undercooling (^T4608C), and derived from a harrisitic mush formed on the cold walls of the magma reservoir. Given thegrowth shapes indicated by P zoning patterns and external faces, the olivine macrocrysts (which consist of groups of several subcrystals) have grown in suspension within the liquid and were neither aggregated into a dense cumulate nor corroded, shocked or deformed before or during their transport to the surface.The major consequence of our study is that most olivine macrocrysts are not xenocrysts, and very few of them, if any, have experienced intracrystalline deformation. The importance of deforming (creeping) cumulate bodies, thought to accommodate the spreading of basaltic volcanoes in La Reunion and Hawaii, may hence have been overestimated.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The olivine macrocrysts found in oceanites, picrites and magnesian basalts erupted at hotspot volcanoes are generally interpreted either as phenocrysts crystallized from the magma or as xenocrysts extracted from a deforming cumulate.To constrain the origin of these crystals we studied their texture and composition at Piton de la Fournaise volcano, La Reunion.We show that macrocrysts are organized andsubdivided into parallel units; this suggests a crystallization by dendriticgrowth and ripening rather than by a complex combination of paired nucleation, crystal aggregation or synneusis. Dendritic growth is also evidenced by the occurrence of hollow faces, P-rich zones, melt and Cr-spinel inclusions formed from the accumulation of slow diffusing impurities (P, Cr, Al) in the liquid at the contact with rapid-growing olivine.We suggest that early dendritic crystallization may even cause branch misorientations and lattice mismatches,yielding subgrain boundaries, dislocation lamellae and to a certain extent undulose extinction, which have all been formerly interpreted in terms of plastic intracrystalline deformation.We interpret olivine macrocrysts as phenocrysts crystallized under a strong degree of undercooling (^T4608C), and derived from a harrisitic mush formed on the cold walls of the magma reservoir. Given thegrowth shapes indicated by P zoning patterns and external faces, the olivine macrocrysts (which consist of groups of several subcrystals) have grown in suspension within the liquid and were neither aggregated into a dense cumulate nor corroded, shocked or deformed before or during their transport to the surface.The major consequence of our study is that most olivine macrocrysts are not xenocrysts, and very few of them, if any, have experienced intracrystalline deformation. The importance of deforming (creeping) cumulate bodies, thought to accommodate the spreading of basaltic volcanoes in La Reunion and Hawaii, may hence have been overestimated. |
2012
|
Colin, A., Faure, F., Burnard, P. Timescales of convection in magma chambers below the Mid-Atlantic ridge from melt inclusions investigations (Article de journal) Dans: Contributions to Mineralogy and Petrology, vol. 164, p. 677–691, 2012. @article{Colin_etal2012,
title = {Timescales of convection in magma chambers below the Mid-Atlantic ridge from melt inclusions investigations},
author = {A. Colin and F. Faure and P. Burnard},
doi = {10.1007/s00410-012-0764-2},
year = {2012},
date = {2012-01-01},
journal = {Contributions to Mineralogy and Petrology},
volume = {164},
pages = {677--691},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Faure, F., Tissandier, L., Libourel, G., Mathieu, R., Welsch, B. Origin of glass inclusions hosted in magnesian porphyritic olivines chondrules: Deciphering planetesimal compositions (Article de journal) Dans: Earth and Planetary Science Letters, vol. 319-320, p. 1–8, 2012. @article{Faure_etal2012,
title = {Origin of glass inclusions hosted in magnesian porphyritic olivines chondrules: Deciphering planetesimal compositions},
author = {F. Faure and L. Tissandier and G. Libourel and R. Mathieu and B. Welsch},
doi = {10.1016/j.epsl.2011.12.013},
year = {2012},
date = {2012-01-01},
journal = {Earth and Planetary Science Letters},
volume = {319-320},
pages = {1--8},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
2011
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Khedim, H., Abdelouhab, S., Podor, R., Rapin, C., Vilasi, M., Panteix, P. J., Toplis, M., Faure, F. Kinetic and equilibrium factors affecting saturation of chromium oxide in soda-silicate melts (Article de journal) Dans: Journal of Non-Crystalline Solids, vol. 357, p. 31–42, 2011. @article{Khedim_etal2011,
title = {Kinetic and equilibrium factors affecting saturation of chromium oxide in soda-silicate melts},
author = {H. Khedim and S. Abdelouhab and R. Podor and C. Rapin and M. Vilasi and P. J. Panteix and M. Toplis and F. Faure},
year = {2011},
date = {2011-01-01},
journal = {Journal of Non-Crystalline Solids},
volume = {357},
pages = {31--42},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Koepke, J., France, L., Müller, T., Faure, F., Goetze, N., Dziony, W., Ildefonse, B. Gabbos from IODP site 1256, equatorial Pacific: Insight into axial magma chamber processes at fast spreading ocean ridges (Article de journal) Dans: Geochemistry, Geophysics, Geosystems G3, vol. 12, no. 9, p. Q09014, 2011. @article{Koepke_etal2011,
title = {Gabbos from IODP site 1256, equatorial Pacific: Insight into axial magma chamber processes at fast spreading ocean ridges},
author = {J. Koepke and L. France and T. M\"{u}ller and F. Faure and N. Goetze and W. Dziony and B. Ildefonse},
doi = {10.1029/2011GC003655},
year = {2011},
date = {2011-01-01},
journal = {Geochemistry, Geophysics, Geosystems G3},
volume = {12},
number = {9},
pages = {Q09014},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
2009
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Bouquain, S., Arndt, N. T., Hellebrand, E., Faure, F. Crystallochemistry and origin of pyroxenes in komatiites (Article de journal) Dans: Contributions to Mineralogy and Petrology, vol. 158, p. 599–617, 2009. @article{Bouquain_etal2009,
title = {Crystallochemistry and origin of pyroxenes in komatiites},
author = {S. Bouquain and N. T. Arndt and E. Hellebrand and F. Faure},
doi = {10.1007/s00410-009-0399-0},
year = {2009},
date = {2009-01-01},
journal = {Contributions to Mineralogy and Petrology},
volume = {158},
pages = {599--617},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Welsch, B., Faure, F., Bach`elery, P., Famin, V. Microcrysts record transient convection at Piton de la Fournaise Volcano (La Réunion Hotspot) (Article de journal) Dans: Journal of Petrology, vol. 50, no. 12, p. 2287–2305, 2009. @article{Welsch_etal2009,
title = {Microcrysts record transient convection at Piton de la Fournaise Volcano (La R\'{e}union Hotspot)},
author = {B. Welsch and F. Faure and P. Bach`elery and V. Famin},
doi = {10.1093/petrology/egp076},
year = {2009},
date = {2009-01-01},
journal = {Journal of Petrology},
volume = {50},
number = {12},
pages = {2287--2305},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
2008
|
Mathieu, R., Khedim, H., Libourel, G., Podor, R., Tissandier, L., Deloule, E., Faure, F., Rapin, C., Vilasi, M. Control of alkali-metal oxide activity in molten silicates (Article de journal) Dans: Journal of Non-Crystalline Solids, vol. 254, no. 45-46, p. 5079–5083, 2008. @article{Mathieu_etal2008,
title = {Control of alkali-metal oxide activity in molten silicates},
author = {R. Mathieu and H. Khedim and G. Libourel and R. Podor and L. Tissandier and E. Deloule and F. Faure and C. Rapin and M. Vilasi},
doi = {10.1016/j.jnoncrysol.2008.07.004},
year = {2008},
date = {2008-01-01},
journal = {Journal of Non-Crystalline Solids},
volume = {254},
number = {45-46},
pages = {5079--5083},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
2007
|
Faure, F., Schiano, P., Trolliard, G., Nicollet, C., Soulestin, B. Textural evolution of polyhedral olivine experiencing rapid cooling rates (Article de journal) Dans: Contributions to Mineralogy and Petrology, vol. 153, no. 4, p. 369–492, 2007. @article{Faure_etal2007,
title = {Textural evolution of polyhedral olivine experiencing rapid cooling rates},
author = {F. Faure and P. Schiano and G. Trolliard and C. Nicollet and B. Soulestin},
doi = {10.1007/s00410-006-0154-8},
year = {2007},
date = {2007-01-01},
journal = {Contributions to Mineralogy and Petrology},
volume = {153},
number = {4},
pages = {369--492},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Moune, S., Faure, F., Gauthier, P. J., Sims, K. W. W. Peletextquoterights hairs and tears: natural probe of volcanic plume (Article de journal) Dans: Journal of Volcanology and Geothermal Research, vol. 164, no. 4, p. 244–253, 2007. @article{Moune_etal2007,
title = {Peletextquoterights hairs and tears: natural probe of volcanic plume},
author = {S. Moune and F. Faure and P. J. Gauthier and K. W. W. Sims},
doi = {10.1016/j.jvolgeores.2007.05.007},
year = {2007},
date = {2007-01-01},
journal = {Journal of Volcanology and Geothermal Research},
volume = {164},
number = {4},
pages = {244--253},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
2006
|
Faure, F., Arndt, N., Libourel, G. Formation of spinifex texture in komatiites: an experimental study (Article de journal) Dans: Journal of Petrology, vol. 47, no. 8, p. 1591–1610, 2006. @article{Faure_etal2006,
title = {Formation of spinifex texture in komatiites: an experimental study},
author = {F. Faure and N. Arndt and G. Libourel},
doi = {10.1016/j.precamres.2006.01.022},
year = {2006},
date = {2006-01-01},
journal = {Journal of Petrology},
volume = {47},
number = {8},
pages = {1591--1610},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Schiano, P., Provost, A., Clocchiatti, R., Faure, F. Transcrystalline melt migration and Earthtextquoterights mantle (Article de journal) Dans: Science, vol. 314, no. 5801, p. 970–974, 2006. @article{Schiano_etal2006,
title = {Transcrystalline melt migration and Earthtextquoterights mantle},
author = {P. Schiano and A. Provost and R. Clocchiatti and F. Faure},
doi = {10.1126/science.1132485},
year = {2006},
date = {2006-01-01},
journal = {Science},
volume = {314},
number = {5801},
pages = {970--974},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
