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15. Linking the Jehol Biota evolution to the Early Cretaceous volcanism during the North China craton destruction:insights from F, Cl, S, and P

Author

Xu, Q.-H. (Qi-Hu), Wang, L. (Lu), Liu, J. (Jia), Deloule, E. (Etienne), Hanski, E. (Eero), Gu, X.-Y. (Xiao-Yan), Chen, H. (Huan), and Xia, Q.-K. (Qun-Ke)

Subjects
North China craton destruction, volcanism, volatiles, phosphorus, Jehol Biota
Abstract

The Early Cretaceous Jehol Biota evolution has remarkable spatiotemporal correlation with the destruction of the North China craton though the coupling mechanism remains enigmatic. The craton destruction was accompanied by intense magmatic activity and the released volatiles and nutrients might have had climatic and environmental impacts on the biotic evolution. In this study, we investigated the mentioned hypothetical causal link by determining concentrations and total emissions of volatile elements (S, F, Cl) and bulk-rock P contents of volcanic rocks that were erupted during the pre-flourishing, flourishing and post-flourishing stages of the Jehol Biota. Our results show that the volcanism near the flourishing stage has lower S (1,083–2,370 ppm), Cl (1,277–5,608 ppm) and higher P₂O₅ contents (0.48–0.84 wt.%) than that in the non-flourishing stages with S of 1,991–3,288 ppm, Cl of 7,915–12,315 ppm and P₂O₅ of 0.17–0.23 wt.%. Fluorine contents in the three stages vary from 893 to 3,746 ppm. The total volatile emissions are minor in the flourishing stage (1–14 Gt S, 0.6–10 Gt Cl, 0.6–9 Gt F) but elevated in the non-flourishing stages (2–766 Gt S, 4–1,168 Gt Cl, 1–175 Gt F). Our data suggest that regional climatic and environmental impacts of volcanism in the non-flourishing stages probably hindered the species diversification. The high P flux released from lithospheric mantle-derived lavas during the peak time of craton destruction might have enhanced primary productivity and contributed to the flourishing of the Jehol Biota. Our study provides insights into the relationship between the biosphere and deep geodynamic processes driven by volcanism.

Published
2022

19. Decadal to monthly timescales of magma transfer and reservoir growth at a caldera volcano

Author

Druitt, T.H., Costa, F., Deloule, E., Dungan, M., and Scaillet, B.

Subjects
Calderas -- Natural history -- Observations, Volcanoes -- Analysis -- Observations -- France, Volcanism -- Analysis -- Research, Magmatism -- Research, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Caldera-forming volcanic eruptions are low-frequency, high-impact events capable of discharging tens to thousands of cubic kilometres of magma explosively on timescales of hours to days, with devastating effects on local and global scales (1). Because no such eruption has been monitored during its long build-up phase, the precursor phenomena are not well understood. Geophysical signals obtained during recent episodes of unrest at calderas such as Yellowstone, USA, and Campi Flegrei, Italy, are difficult to interpret, and the conditions necessary for large eruptions are poorly constrained (2,3). Here we present a study of pre-eruptive magmatic processes and their timescales using chemically zoned crystals from the 'Minoan' caldera-forming eruption of Santorini volcano, Greece (4), which occurred in the late 1600s bc. The results provide insights into how rapidly large silicic systems may pass from a quiescent state to one on the edge of eruption (5,6). Despite the large volume of erupted magma (4) (40-60 cubic kilometres), and the 18,000-year gestation period between the Minoan eruption and the previous major eruption, most crystals in the Minoan magma record processes that occurred less than about 100 years before the eruption. Recharge of the magma reservoir by large volumes of silicic magma (and some mafic magma) occurred during the century before eruption, and mixing between different silicic magma batches was still taking place during the final months. Final assembly of large silicic magma reservoirs may occur on timescales that are geologically very short by comparison with the preceding repose period, with major growth phases immediately before eruption. These observations have implications for the monitoring of long-dormant, but potentially active, caldera systems., Crystals in volcanic rocks provide records of magma reservoir processes and timescales before eruptions (7). A crystal growing from a magmatic melt incorporates trace elements in quantities governed by thermodynamic [...]

Published
2012
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20. Apport des géosciences en archéologie minière : l’exemple de Brandes (commune d’Huez, massif des Grandes Rousses)

Author

Deroin, Jean-Paul, Deloule, E., Marignac, C., Bailly-Maître, Marie-Christine, Groupe d'Étude sur les Géomatériaux et Environnements Naturels, Anthropiques et Archéologiques - EA 3795 (GEGENAA), Université de Reims Champagne-Ardenne (URCA)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Maison des Sciences Humaines de Champagne-Ardenne (MSH-URCA), and Université de Reims Champagne-Ardenne (URCA)-Université de Reims Champagne-Ardenne (URCA)

Subjects
[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, [SHS.GEO]Humanities and Social Sciences/Geography, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2020

22. Dehydrogenation of kaersutitic amphibole under electron beam excitation recorded by changes in [Fe.sup.3+]/[summation]Fe: an EMP and SIMS study

Author

Wagner, C., Deloule, E., Fialin, M., and King, P.L.

Subjects
Amphiboles -- Composition, Dehydrogenation -- Observations, Electron beams -- Influence, Mass spectrometry -- Methods, Earth sciences
Abstract

We present in situ microanalyses of [Fe.sup.3]+[summation]Fe in mantle-derived kaersutites as measured by electron probe microanalysis (EMP) based on the 'self absorption induced FeL[alpha] peak shift' method. The EMP results are not in agreement with bulk (wet chemistry) data. The heterogeneities revealed for some kaersutite megacrysts, when comparing bulk and EMP [Fe.sup.3+]/[summation]Fe results, cannot explain the differences with the EMP measurements. It is thus proposed that any EMP overestimation of [Fe.sup.3+]/[summation]Fe results from a beam-induced dehydrogenation and a subsequent oxidation of [Fe.sup.2+] to [Fe.sup.3+] according to the known relation: [Fe.sup.2+] + O[H.sup.-] = [Fe.sup.3+] + [O.sup.2-] + 1/2 [H.sub.2]. To demonstrate this phenomenon, H losses were measured by secondary ion mass spectrometry (SIMS) after EMP irradiation at different beam currents on two amphiboles with 1.1 and 1.7 wt% [H.sub.2]O, respectively. In both amphiboles, H losses were observed under high beam currents (240 and 100 nA). No dehydrogenation is observed under lower beam currents for the 1.1 wt% [H.sub.2]O amphibole, but still occurs, down to at least 50 nA, for the amphibole with the greatest [H.sub.2]O contents. Amphiboles with low [H.sub.2]O contents (below ~0.5 [H.sup.+]) are less affected by beam damage. For amphiboles with higher [H.sub.2]O contents, the electron beam current density should be reduced with consideration given to the resulting high statistical errors. Keywords: [Fe.sup.3+]/[summation]Fe, EMP and SIMS measurements, amphibole, H loss

Published
2008

24. New constraints on metamorphic history of Adirondack diopsides (New York, U.S.A.): Al and [[delta].sup.18]O profiles

Author

Desbois, G., Ingrin, J., Kita, N.T., Valley, J.W., and Deloule, E.

Subjects
Metamorphism (Geology) -- Analysis, Oxygen -- Isotopes, Oxygen -- Analysis, Earth sciences
Abstract

Detailed electron- and ion-microprobe analysis ofdiopsides extracted from a block of marble collected in the Mt. Marcy anorthosite massif (Adirondack Highlands, New York) shows that single crystals have preserved Al-Si zoning features from early contact metamorphism later modified by regional metamorphism. Diopsides show Al and Si complementary zoning from core to rim; average A1 concentration in rims is constant (0.11 pfu), but values in the cores vary with crystals from 0.06 to 0.14 pfu. A [[delta].sup.18]O profile measured with the ion microprobe shows no zoning. Modeling of the Al-diffusion profiles affected by regional metamorphism of the Grenville orogeny shows that original Al zoning was sharp and corresponds to a rapid change of crystal-growth conditions during early contact metamorphism: (1) diopside cores crystallized with variable Al contents due to restricted fluid circulation or differing sedimentary composition, (2) then pervasive fluid infiltration crystallized the homogeneous rim of diopside, and (3) core to rim Al zoning was later smoothed by granulite-facies metamorphism. Homogeneity of [[delta].sup.18]O in core and mantle (near rim) of diopsides suggests that the crystals were isotopically homogeneous prior to and during regional metamorphism. Values of Al-Si diffusion coefficient deduced from modeling are in agreement with low-temperature extrapolation of experimental data. Keywords: Diopside, zoning, granulite, diffusion, ion probe, oxygen isotopes, Adirondack

Published
2007

35. Iron isotopes in micropyrites from the 2.7Ga Tumbiana Formation (Western Australia)

Author

Decraene, M.-N., Marin- Carbonne, J., Thomazo, C., Olivier, Nicolas, Philippot, P., Deloule, E., Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Géosciences Montpellier, Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement et la société-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Université Jean Monnet [Saint-Étienne] (UJM), Biogéosciences [UMR 6282] [Dijon] (BGS), Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), and Jouhannel, Sylvaine

Subjects
[SDU.STU.PG] Sciences of the Universe [physics]/Earth Sciences/Paleontology, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology
Abstract

International audience; Stromatolites are considered to be the major drivers for the oceanic oxygenation during Archean time. However, respective rolesof photosynthetic and chemolithotroph organisms in these Archean rocks is not precisely demonstrated. Primarysub-micrometer pyrites associated with pristine organic matter are widespreadin Archean and modern sediments. Iron isotopes are fractionated by redox processesand biological activitiesand are widely used for tracing paleoredox conditions, diagenetic processes ormetabolic signaturesas iron respiration (DIR). Sub micrometer δ56Fevalues ofmicropyritesassociated with organic matter-laminae and CaCO3-SiO2matrixin stromatolites from the 2.7Ga Tumbiana Formationhave been measured by SIMS using the new Hyperion RF Plasma source. Iron isotope compositions of micropyritesdisplaya wide rangeof valuesfrom-2.20‰ to +4.44‰,comparable to the entire rangeof known terrestrialiron isotopevalues (between-2.4‰ and +2‰). Our data show a large and continuous range defined by more positive values compared to thebimodal distributionpreviously described(Yoshiya et al., 2012). Our results areinterpreted as an interplay between abioticoxidationand biological induced reductionprocessesduring iron cycling at the biofilm scale.

Published
2019

36. Chapitre 3.1. Les minéralisations du massif des Rousses dans le secteur d’Huez

Author

Deroin, Jean-Paul, Marignac, Ch., Deloule, E., Groupe d'Étude sur les Géomatériaux et Environnements Naturels, Anthropiques et Archéologiques - EA 3795 (GEGENAA), Université de Reims Champagne-Ardenne (URCA)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Maison des Sciences Humaines de Champagne-Ardenne (MSH-URCA), and Université de Reims Champagne-Ardenne (URCA)-Université de Reims Champagne-Ardenne (URCA)

Subjects
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2019

45. Sources du Plomb et des fluides de la minéralisation Pb-Zn-Ag du district polymétallique Tighza-Jbel Aouam (Maroc central) et contexte géodynamique

Author

Rossi, Magali, Gasquet, Dominique, Cheilletz, Alain, Tarrieu, Leïla, Bounajma, Hassan, Mantoy, Tristan, Reisberg, L., Deloule, E., Boulvais, Philippe, Burnard, P., Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale Supérieure de Géologie (ENSG), Université de Lorraine (UL), Compagnie minière de Touissit (CMT), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Centre National de la Recherche Scientifique (CNRS), Referent HAL Edytem, Christine Maury, Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.MCG] Environmental Sciences/Global Changes, [SDE.IE]Environmental Sciences/Environmental Engineering, [SHS.GEO] Humanities and Social Sciences/Geography, [SDE.MCG]Environmental Sciences/Global Changes, [SDE.IE] Environmental Sciences/Environmental Engineering, [SDE.ES] Environmental Sciences/Environmental and Society, [SHS.GEO]Humanities and Social Sciences/Geography, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDE.ES]Environmental Sciences/Environmental and Society, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017

46. Isotopic and trace element characteristics of an unusual refractory inclusion from Essebi

Author

Deloule, E, Kennedy, A. K, Hutcheon, I. D, and Elgoresy, A

Subjects
Solar Physics
Abstract

The isotopic and chemical properties of Ca-Al-rich inclusions (CAI) provide important clues to the early solar nebula environment. While the abundances of refractory major and trace elements are similar to those expected for high temperature condensates, the variety of textural, chemical, and isotopic signatures indicate most CAI experienced complex, multi-stage histories involving repeated episodes of condensation, evaporation, and metamorphism. Evidence of multiple processes is especially apparent in an unusual refractory inclusion from Essebi (URIE) described by El Goresy et al. The melilite (mel)-rich core of URIE contains polygonal framboids of spinel (sp) and hibonite (hb) or sp and fassaite (fas) and is surrounded by a rim sequence consisting of five layers. In contrast to rims on Allende, the mineralogy of the URIE rim layers becomes increasingly refractory from the core outwards, ending in a layer of spinel-Al2O3 solid solution + Sc-rich fassaite. The chemical and mineralogical features of URIE are inconsistent with crystallization from a homogeneous melt, and El Goresy et al. proposed a multi-step history involving condensation of sp + hb and aggregation into framboids, capture of framboids by a refractory silicate melt droplet, condensation of rim layers, and alteration of mel to calcite and feldspathoid. The PANURGE ion probe was used to investigate the isotopic and trace element characteristics of URIE to develop a more complete picture of the multiple processes leading to formation and metamorphism.

Published
1993

47. Evidence for an Active, Transcrustal Magma System in the Last 60 ka and Eruptive Degassing Budget (H2O, CO2, S, F, Cl, Br): The Case of Dominica.

Author

d'Augustin, T., Balcone-Boissard, H., Boudon, G., Martel, C., Deloule, E., and Bürckel, P.

Subjects
VOLCANIC eruptions, VOLCANOES, IGNIMBRITE, HALOGENS
Abstract

The Morne Trois Pitons-Micotrin volcanic complex on the island of Dominica (Lesser Antilles) emitted a series of plinian eruptions between 18 and 9 ka BP. We studied it to constrain magma storage conditions and volatile degassing balances, by comparison with the three previous ignimbrites (~60-24 ka BP). Volatile concentrations in glass inclusions and mineral-melt thermobarometry indicate storage at ≤200 MPa (~6-8 km) and 860-880°C. The magmas feeding these plinian eruptions were stored at a shallower depth than those that older ignimbrites from the same volcanic complex and stored at ~16 km. Close magma composition and similar halogen ratios, however, suggest a common source for the magmas feeding both the plinian eruptions and the ignimbrites. The large eruptive fluxes of F, Cl, and Br to the atmosphere (up to 1.4-2.8 × 10-1 Mt/km³, 1.5-4.0 Mt/km³, and 2-4 × 10-2 Mt/km³, respectively), estimated by the petrological method, support the potentially important role of volcanic halogens in modifying the chemistry of the atmosphere, though Cl is underestimated here because of buffering in a fluid phase. The behavior of S, potentially partitioned in the same fluid phase, prevents here the calculation of an eruptive outgassing budget. [ABSTRACT FROM AUTHOR]

Published
2020
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48. U/Pb ages of magmatism in the Zgounder epithermal Ag-Hg deposit, Sirwa window, Anti-Atlas, Morocco

Author

Pelleter, E., Cheilletz, Alain, Gasquet, Dominique, Mouttaqi, A, Annich, M, Camus, Q., Deloule, E., ouazzani, l, Bounajma, Hassan, Ouchtouban, L., GeoRessources, Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Centre de recherches sur la géologie des matières premières minérales et énergétiques (CREGU)-Institut national des sciences de l'Univers (INSU - CNRS), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Compagnie minière de Touissit (CMT), Bouabdellah M., Slack J., and Referent HAL Edytem, Christine Maury

Subjects
[SDE.BE] Environmental Sciences/Biodiversity and Ecology, [SDE.MCG] Environmental Sciences/Global Changes, [SDE.IE]Environmental Sciences/Environmental Engineering, [SHS.GEO] Humanities and Social Sciences/Geography, [SDE.MCG]Environmental Sciences/Global Changes, [SDE.IE] Environmental Sciences/Environmental Engineering, [SDE.ES] Environmental Sciences/Environmental and Society, [SHS.GEO]Humanities and Social Sciences/Geography, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDE.ES]Environmental Sciences/Environmental and Society, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

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