Author: "Lexa, O." - Searchworks@Jio Institute Digital Library Search Results

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152 results on '"Lexa, O."'

1. Structures and geodynamics of the Mongolian tract of the Central Asian Orogenic Belt constrained by potential field analyses

Author: Guy, Alexandra, Schulmann, K., Soejono, I., Holzrichter, N., Lexa, O., and Munschy, M.
Published: 2021
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2. Thermal and mechanical evolution of collisional and accretionary orogens: a volume in honour of Karel Schulmann—an introduction

Author: Štípská, P., Hasalová, P., Jeřábek, P., Lexa, O., Lardeaux, J. M., Sun, M., and Cosgrove, J. W.
Published: 2020
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3. Deformation pattern of the Lower Triassic sedimentary formations of the Silica Nappe: Evidence for dynamics of the Western Carpathian orogen

Author: Vojtko, R., primary, Lačný, A., additional, Jeřábek, P., additional, Potočný, T., additional, Gerátová, S., additional, Kilík, J., additional, Plašienka, D., additional, and Lexa, O., additional
Published: 2023
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4. Impact of solid second phases on deformation mechanisms of naturally deformed salt rocks (Kuh-e-Namak, Dashti, Iran) and rheological stratification of the Hormuz Salt Formation

Author: Závada, P., Desbois, G., Urai, J.L., Schulmann, K., Rahmati, M., Lexa, O., and Wollenberg, U.
Published: 2015
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5. Re-evaluation of polyphase kinematic and 40Ar/39Ar cooling history of Moldanubian hot nappe at the eastern margin of the Bohemian Massif

Author: Racek, M., Lexa, O., Schulmann, K., Corsini, M., Štípská, P., and Maierová, P.
Published: 2017
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6. Paleozoic Geodynamics and Architecture of the Southern Part of the Mongolian Altai Zone

Author: Sukhbaatar, T., primary, Lexa, O., additional, Schulmann, K., additional, Aguilar, C., additional, Štípská, P., additional, Wong, J., additional, Jiang, Y., additional, Míková, J., additional, and Zhao, D., additional
Published: 2022
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7. U-Pb-Th geochronology of monazite and zircon in albitite metasomatites of the Rožňava-Nadabula ore field (Western Carpathians, Slovakia): implications for the origin of hydrothermal polymetallic siderite veins

Author: Hurai, V., Paquette, J.-L., Lexa, O., Konečný, P., and Dianiška, I.
Published: 2015
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8. Alpine burial and heterogeneous exhumation of Variscan crust in the West Carpathians: insight from thermodynamic and argon diffusion modelling

Author: Jerabek, P., Faryad, W.S., Schulmann, K., Lexa, O., and Tajcmanova, L.
Subjects: Carpathian Mountains -- Natural history, Thermodynamics -- Research, Argon -- Properties, Orogeny -- Models, Geological research, Earth sciences
Abstract: Phase equilibrium modelling of metagranitoids and metapelites in the MnO-[Na.sub.2]O-CaO-[K.sub.2]O-FeO-MgO-[Al.sub.2][O.sub.3]-Si[O.sub.2]- [H.sub.2]O system was used to characterize Variscan and Alpine metamorphism in the crystalline basement of the Vepor Unit, West Carpathians. The calculated P-T conditions range between 570 670[degrees]C and 6-8.5 kbar for the Variscan and 430-600[degrees]C and 5-11 kbar for the Alpine event. These two events show contrasting metamorphic field gradients and P T evolutions, indicating 22 27 [degrees]C [km.sup.-1] during the retrograde Variscan metamorphism and 15-18 [degrees]C [km.sup.-1] during the prograde Alpine metamorphism. The prograde Alpine metamorphism is associated with the Early Cretaceous overthrusting of the southern Gemer Unit, which resulted in apparently contemporaneous burial and horizontal ductile spreading of the underlying Vepor basement. The argon diffusion modelling was used to interpret the existing Variscan, Alpine and mixed [sup.40]Ar/[sup.39]Ar cooling ages, and to constrain the T-t evolution and Alpine thermal overprint. Constructed Alpine metamorphic isograds and isotherms show horizontal P-T gradients resulting from heterogeneous exhumation of the deeper parts of the Vepor basement along two narrow belts during later folding. Here the structurally deeper metapelites form large-scale anticlinal cusp-like structures that separate structurally higher metagranitoids.
Published: 2008

9. Kinematic and rheological model of exhumation of high pressure granulites in the Variscan orogenic root: example of the Blanský les granulite, Bohemian Massif, Czech Republic

Author: Franěk, J., Schulmann, K., and Lexa, O.
Published: 2006
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10. Metamorphic record of burial and exhumation of orogenic lower and middle crust: a new tectonothermal model for the Drosendorf window (Bohemian Massif, Austria)

Author: Racek, M., Štípská, P., Pitra, P., Schulmann, K., and Lexa, O.
Published: 2006
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11. Making continental crust: origin of Devonian orthogneisses from SE Mongolian Altai

Author: Buriánek, D., Janoušek, V., Hanžl, P., Jiang, Yuchao, Schulmann, K., Lexa, O., Altanbaatar, B., Edel, J., Maurer, V., Dalmais, E., Genter, A., Richard, A., Letourneau, O., Hehn, R., Czech Geological Survey [Praha], Department of Physics [Davis], University of California [Davis] (UC Davis), University of California-University of California, Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Mongolian Academy of Sciences (MAS), GEIE Exploitation Minière de la Chaleur, GEIE, Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)
Subjects: 2. Zero hunger, Czech, [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, 010504 meteorology & atmospheric sciences, Continental crust, 15. Life on land, 010502 geochemistry & geophysics, 01 natural sciences, Chinese academy of sciences, Archaeology, language.human_language, Devonian, 13. Climate action, Isotope geochemistry, Geological survey, language, General Earth and Planetary Sciences, China, Structural geology, Geomorphology, Geology, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: 1 Czech Geological Survey, Klarov 3, 118 21 Prague 1, Czech Republic; pavel.hanzl@geology.cz 2 Ecole et Observatoire des Sciences de la Terre, Universite de Strasbourg, UMR 7516 of CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France 3 Institute of Petrology and Structural Geology, Charles University in Prague, Faculty of Science, Albertov 6, 128 43 Prague 2, Czech Republic 4 Institute of Paleontology and Geology, Mongolian Academy of Sciences, Ulaanbaatar 15160, Mongolia 5 School of Geology and Mining Engineering, MUST, P.O. Box 654, Ulaanbaatar, Mongolia 6 State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China * Corresponding author
Published: 2018
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12. Neoproterozoic-Early Paleozoic Peri-Pacific Accretionary Evolution of the Mongolian Collage System: Insights From Geochemical and U-Pb Zircon Data From the Ordovician Sedimentary Wedge in the Mongolian Altai

Author: Jiang, D., Schulmann, K., KrÖner, A., Sun, M., Lexa, O., Janoušek, V., Buriánek, D., Yuan, C., Hanžl, P., Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Geology [CAGS Beijing] (CAGS), Chinese Academy of Geological Sciences [Beijing] (CAGS), Ministry of Land and Resources (MLR)-Ministry of Land and Resources (MLR), and Czech Geological Survey [Praha]
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2017
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13. Anatexis of accretionary wedge, Pacific-type magmatism, and formation of vertically stratified continental crust in the Altai Orogenic Belt

Author: Jiang, Yuchao, Schulmann, K., Sun, M., ŠtÍpskÁ, P., Guy, A., Janoušek, V., Lexa, O., Yuan, C., Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherches sur la catalyse (IRC), Centre National de la Recherche Scientifique (CNRS), and Czech Geological Survey [Praha]
Subjects: [SDU]Sciences of the Universe [physics], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2016
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14. European Variscan orogenic evolution as an analogue of Tibetan-Himalayan orogen: Insights from petrology and numerical modeling

Author: Maierová, P., Schulmann, K., Lexa, O., Guillot, S., ŠtÍpskÁ, P., Janoušek, V., Čadek, O., Czech Geological Survey [Praha], Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géodynamique des Chaines Alpines (LGCA), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Institut des Sciences de la Terre (ISTerre), and Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: [SDU]Sciences of the Universe [physics], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2016
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15. Continuity of the Alpine slab unraveled by high-resolution P-wave tomography

Author: Maierová, P., Schulmann, K., Lexa, O., ŠtÍpskÁ, P., Janoušek, V., Čadek, O., Zhao, Liang, Paul, Anne, Malusà, Marco, Xu, Xiaobing, Zheng, Tianyu, Solarino, Stefano, Guillot, Stéphane, Schwartz, Stéphane, Dumont, Thierry, Salimbeni, Simone, Aubert, Coralie, Pondrelli, Silvia, Wang, Qingchen, Zhu, Rixiang, Czech Geological Survey [Praha], Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Petrology and Structural geology, Charles University [Prague], Ecole et Observatoire des Sciences de la Terre (EOST), Tianjin University (TJU), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), University of Milano - Bicocca, Laboratoire d'Electronique et Electromagnétisme (L2E), Sorbonne Université (SU), Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Institut Camille Jordan [Villeurbanne] (ICJ), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS), Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Bologna (INGV), Istituto Nazionale di Geofisica e Vulcanologia, Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS), Department of Earth and Planetary Sciences [Kobe], and Kobe University
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU]Sciences of the Universe [physics], [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2016
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16. Geophysical and geochemical nature of relaminated arc-derived lower crust underneath oceanic domain in southern Mongolia

Author: Guy, Alexandra, Schulmann, Karel, Janoušek, V., ŠtÍpskÁ, P., Armstrong, R, Belousova, E, Dolgopolova, A, Seltmann, Reimar, Lexa, O, Jiang, Y, Hanžl, P, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), and Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2015
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17. Permian clockwise rotation of the Ebro and Corso-Sardinian blocks during Iberian-Armorican oroclinal bending: Preliminary paleomagnetic data from the Catalan Coastal Range (NE Spain)

Author: Edel, J. B., Schulmann, Karel, Lexa, O, Diraison, Marc, Géraud, Yves, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and SCHOLASTIQUE, ELODIE
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.GP] Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2015

18. Mid-crustal shear zone formation in granitic rocks: Constraints from quantitative textural and crystallographic preferred orientations analyses

Author: Oliot , Emilien, Goncalves , Philippe, Schulmann , Karel, Marquer , Didier, Lexa , O., Dylbas, Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Université de Franche-Comté ( UFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Bourgogne Franche-Comté ( UBFC ) -Université de Franche-Comté ( UFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Institut de physique du globe de Strasbourg ( IPGS ), Université de Strasbourg ( UNISTRA ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Université Bourgogne Franche-Comté ( UBFC ) -Université de Franche-Comté ( UFC ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de physique du globe de Strasbourg ( IPGS ), Université de Strasbourg ( UNISTRA ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Charles University [Prague], Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), and Charles University [Prague] (CU)
Subjects: Gotthard Massif, EBSD, Shear zone formation, Deformation mechanisms, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, Strain localization, Quantitative textural analysis, [ SDU.STU.PE ] Sciences of the Universe [physics]/Earth Sciences/Petrography
Abstract: International audience; This paper presents quantitative microstructural and crystallographic preferred orientation (CPO) analyses of an Alpine amphibolite facies shear zone developed in the Fibbia metagranite (Gotthard massif, Central Alps). The weakly deformed metagranite and orthogneiss at the margins of the shear zone are characterized by a bulk strain partitioning between harder coarse-grained monomineralic aggregates, derived from quartz and K-feldspar porphyroclasts, and softer fine-grained plagioclase-bearing shear bands. A characteristic feature is a dilatant fracturing of strong quartz and feldspar aggregates. CPOs and microtextures suggest that quartz and K-feldspar aggregates are dynamically recrystallized via dislocation creep while plagioclases show evidences of fluid-assisted diffusive mass transfer and grain boundary sliding. In the mylonite and ultramylonite shear zone core, the porphyroclasts-derived quartz and K-feldspar layers are broken-down to produce a polyphased matrix that is characterized by a homogeneous micron-scale grain size and regular/random distribution. Here, the deformation of the whole aggregate occurs via a fluid-assisted dissolution-precipitation creep and grain boundary sliding, referred as a fluid-assisted granular flow. We propose a model of shear zone formation associated with the nucleation of shear zone followed by lateral widening of the sheared domain. The lateral broadening of the shear zone is driven by (1) the increase in fluid pressure in permeable albite-oligoclase shear bands that results in expulsion of fluids to the shear zone margins and hydraulic fracturing of strong aggregates, and (2) the thermodynamic re-equilibration via metasomatic reactions of the shear zone walls.
Published: 2014

19. Anatomy of a diffuse cryptic suture zone: An example from the Bohemian Massif, European variscides: invited reply

Author: Schulmann, Karel, Lexa, O, Janoušek, V, Lardeaux, J.M, Edel, J.B, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and SCHOLASTIQUE, ELODIE
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2014

20. Geophysical constraints for terrane boundaries in southern Mongolia

Author: Guy, A, Schulmann, Karel, Munschy, Marc, Miehe, J.-M, Edel, J.B., Lexa, O, Fairhead., D, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), and Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2014
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21. Late Paleozoic-Mesozoic tectonic evolution of the Trans-Altai and South Gobi Zones in southern Mongolia based on structural and geochronological data

Author: Guy, Alexandra, Schulmann, Karel, Clauer, N., Hasalová, P, Seltmann, R., Armstrong, R, Lexa, O, Benedicto, A, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), and Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2014

22. Palaeomagnetic and structural constraints on 90° anticlockwise rotation in SW Mongolia during the Permo-Triassic: Implications for Altaid oroclinal bending. Preliminary palaeomagnetic results

Author: Edel, J.B., Schulmann, Karel, Hanžl, P, Lexa, O, SCHOLASTIQUE, ELODIE, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), and Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.GP] Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2014

23. Metamorphic inheritance of Rheic passive margin evolution and its early‐Variscan overprint in the Teplá‐Barrandian Unit, Bohemian Massif

Author: Peřestý, V., primary, Lexa, O., additional, Holder, R., additional, Jeřábek, P., additional, Racek, M., additional, Štípská, P., additional, Schulmann, K., additional, and Hacker, B., additional
Published: 2016
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24. Re-evaluation of polyphase kinematic and 40Ar/39Ar cooling history of Moldanubian hot nappe at the eastern margin of the Bohemian Massif

Author: Racek, M., primary, Lexa, O., additional, Schulmann, K., additional, Corsini, M., additional, Štípská, P., additional, and Maierová, P., additional
Published: 2016
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25. Petrogenesis of the Late Carboniferous Sagsai Pluton in the SE Mongolian Altai

Author: Buriánek, D., primary, Janoušek, V., additional, Hanžl, P., additional, Jiang, Y., additional, Schulmann, K., additional, Lexa, O., additional, and Altanbaatar, B., additional
Published: 2016
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26. Making continental crust: origin of Devonian orthogneisses from SE Mongolian Altai

Author: Hanžl, P., primary, Schulmann, K., additional, Janoušek, V., additional, Lexa, O., additional, Hrdličková, K., additional, Jiang, Y., additional, Buriánek, D., additional, Altanbaatar, B., additional, Ganchuluun, T., additional, and Erban, V., additional
Published: 2016
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27. Structural and anisotropy of magnetic susceptibility records of granitoid sheets emplacement during growth of a continental gneiss dome (Central Sudetes, European Variscan Belt)

Author: Lehmann, J., Schulmann, Karel, Edel, J.-B., Jezek, Josef, Hrouda, F., Lexa, O., Chopin, F., Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Applied Mathematics (KAM) (KAM), Univerzita Karlova v Praze, Institute of Petrology and Structural Geology (IPSG), Charles University [Prague] (CU), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Ecole et Observatoire des Sciences de la Terre (EOST), and ANR-06-BLAN-0352,LFO in orogens,Laterally-forced overturns (LFO) enhanced by melt induced softening (MIS) in orogens: new model for continental tectonics(2006)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, PLASTIC-DEFORMATION, NORTHEASTERN MARGIN, [SDE.MCG]Environmental Sciences/Global Changes, EASTERN VARISCIDES, FABRIC DEVELOPMENT, BOHEMIAN MASSIF, TONALITE SILL, MELT SEGREGATION, PRE-VARISCAN
Abstract: International audience; Granitoid magmatic sheets emplaced syntectonically during growth of the Orlica-nienik mantled gneiss dome (Central Sudetes, European Variscan belt) were examined by means of structural geology, quartz, and anisotropy of magnetic susceptibility (AMS) fabric studies. Magmatic emplacement was localized along the eastern transpressive margin of the high metamorphic core and below the low-grade detached mantle rimming the southern margin of the dome. In the first area, the magmatic sheets were emplaced parallel to the dilated subhorizontal foliation of an anisotropic pre-orogenic block. The resulting melt-host rock multilayer localized the transpressive zone along which the bulk of magma was emplaced. The AMS study shows an across-strike fabric zonation underlying a strongly transpressive solid-state deformation in the hanging-wall, magmatic subhorizontal fabric in the foot-wall and a transitional fabric in the center of the intrusion. In contrast, along the southern dome margin, magmatic sheets intruded along steep foliations of weakly metamorphic mantle rocks, and are affected by recumbent folding and subhorizontal shearing. The bulk of the sheets present a shallow-dipping magmatic foliation and an along-strike magmatic lineation. The variations of the quartz and magnetic fabrics are attributed to superimposition of pure shear-dominated ductile thinning followed by simple shear-dominated detachment onto the original steep fabric. AMS modeling confirms the role of variation of orientation of pre-intrusive anisotropy during progressive deformation on the resulting fabric pattern and helps explaining observed variations in fabric orientations and symmetries. This study highlights contrasting mechanical behavior of syntectonically emplaced magmas in different parts of a growing crustal-scale mantled gneiss dome. Keywords
Published: 2013

28. Structure and development of a mantled gneiss dome within a continental wedge: (Sudetes, European Variscan belt)

Author: Chopin, F., Schulmann, Karel, Skrzypek, Etienne, Lehmann, J., Martelat, Jean-Emmanuel, Lexa, O., Corsini, M., Dujardin, Jean-Rémi, Edel, J.B., Stipska, Pavla, Pitra, Pavel, Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Ecole et Observatoire des Sciences de la Terre (EOST), Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Czech Geological Survey [Praha], Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Institute of Petrology and Structural geology, Charles University [Prague] (CU), Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Géophysique expérimentale (IPGS) (IPGS-GE), Terre, Temps, Traçage, 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)-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), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), 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)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and 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)
Subjects: [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2012

29. Microstructural and metamorphic evolution of a high-pressure granitic orthogneiss during continental subduction (Orlica-Snieznik dome, Bohemian Massif)

Author: Chopin, Francis, Schulmann, Karel, ŠtÍpskÁ, P., Martelat, J., Pitra, P., Lexa, O, Petri, Benoit, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Czech Geological Survey [Praha], Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Terre, Temps, Traçage, 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)-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), Institute of Petrology and Structural geology, Charles University [Prague] (CU), ANR-06-BLAN-0352,LFO in orogens,Laterally-forced overturns (LFO) enhanced by melt induced softening (MIS) in orogens: new model for continental tectonics(2006), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), 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)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and 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)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, eclogite granitic orthogneiss, petrological modelling, quantitative microstructural analysis, [SDE.MCG]Environmental Sciences/Global Changes, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, European Variscan belt, ComputingMilieux_MISCELLANEOUS, crust rheology
Abstract: International audience; A microstructural and metamorphic study of a naturally deformed medium- to high-pressure granitic orthogneiss (OrlicaSnieznik dome, Bohemian Massif) provides evidence of behaviour of the felsic crust during progressive burial along a subduction-type apparent thermal gradient (similar to 10 degrees C km-1). The granitic orthogneisses develops three distinct microstructural types, as follows: type I augen orthogneiss, type II banded orthogneiss and type III mylonitic orthogneiss, each representing an evolutionary stage of a progressively deformed granite. Type I orthogneiss is composed of partially recrystallized K-feldspar porphyroclasts surrounded by wide fronts of myrmekite, fully recrystallized quartz aggregates and interconnected monomineralic layers of recrystallized plagioclase. Compositional layering in the type II orthogneiss is defined by plagioclase- and K-feldspar-rich layers, both of which show an increasing proportion of interstitial minerals, as well as the deformation of recrystallized myrmekite fronts. Type III orthogneiss shows relicts of quartz and K-feldspar ribbons preserved in a fine-grained polymineralic matrix. All three types have the same assemblage (quartz + plagioclase + K-feldspar + muscovite + biotite + garnet + sphene +/- ilmenite), but show systematic variations in the composition of muscovite and garnet from types I to III. This is consistent with the equilibration of the three types at different positions along a prograde P-T path ranging from 700 degrees C (types II and III orthogneisses). The deformation types thus do not represent evolutionary stages of a highly partitioned deformation at constant P-T conditions, but reflect progressive formation during the burial of the continental crust. The microstructures of the type I and type II orthogneisses result from the dislocation creep of quartz and K-feldspar whereas a grain boundary sliding-dominated diffusion creep regime is the characteristic of the type III orthogneiss. Strain weakening related to the transition from type I to type II microstructures was enhanced by the recrystallization of wide myrmekite fronts, and plagioclase and quartz, and further weakening and strain localization in type III orthogneiss occurred via grain boundary sliding-enhanced diffusion creep. The potential role of incipient melting in strain localization is discussed.
Published: 2012
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30. Crustal influx, indentation, ductile thinning and gravity redistribution in a continental wedge: Building a Moldanubian mantled gneiss dome with underthrust Saxothuringian material (European Variscan belt)

Author: Chopin, F., Schulmann, K., Skrzypek, E., Lehmann, J., Dujardin, J.R., Martelat, J.-E., Lexa, O., Corsini, M., Edel, J.B., Štipska, P., Pitra, Pavel, Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Czech Geological Survey [Praha], Géophysique expérimentale (IPGS) (IPGS-GE), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Institute of Petrology and Structural geology, Charles University [Prague] (CU), Terre, Temps, Traçage, Géosciences Rennes (GR), 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)-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), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), 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)-Université de Rennes 1 (UR1), and 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)
Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: 27 p.; International audience; [1] The contribution of lateral forces, vertical load, gravity redistribution and erosion to the origin of mantled gneiss domes in internal zones of orogens remains debated. In the Orlica-Snieznik dome (Moldanubian zone, European Variscan belt), the polyphase tectono-metamorphic history is initially characterized by the development of subhorizontal fabrics associated with medium- to high-grade metamorphic conditions in different levels of the crust. It reflects the eastward influx of a Saxothuringian-type passive margin sequence below a Teplá-Barrandian upper plate. The ongoing influx of continental crust creates a thick felsic orogenic root with HP rocks and migmatitic orthogneiss. The orogenic wedge is subsequently indented by the eastern Brunia microcontinent producing a multiscale folding of the orogenic infrastructure. The resulting kilometre-scale folding is associated with the variable burial of the middle crust in synforms and the exhumation of the lower crust in antiforms. These localized vertical exchanges of material and heat are coeval with a larger crustal-scale folding of the whole infrastructure generating a general uplift of the dome. It is exemplified by increasing metamorphic conditions and younging of 40Ar/39Ar cooling ages toward the extruded migmatitic subdomes cored by HP rocks. The vertical growth of the dome induces exhumation by pure shear-dominated ductile thinning laterally evolving to non-coaxial detachment faulting, while erosion feeds the surrounding sedimentary basins. Modeling of the Bouguer anomaly grid is compatible with crustal-scale mass transfers between a dense superstructure and a lighter infrastructure. The model implies that the Moldanubian Orlica-Snieznik mantled gneiss dome derives from polyphase recycling of Saxothuringian material.
Published: 2012
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31. The juxtaposition of eclogite and mid-crustal rocks in the Orlica-Snieznik Dome, Bohemian Massif

Author: Štipska, P., Chopin, F., Skrzypek, E., Schulmann, K., Pitra, Pavel, Lexa, O., Martelat, J.-E., Bollinger, C., Zackova, E., Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Terre, Temps, Traçage, Géosciences Rennes (GR), 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), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-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), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Institute of Petrology and Structural geology, Charles University [Prague] (CU), Czech Geological Survey [Praha], Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), 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)-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), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Bohemian Massif, pseudosection modelling, eclogite, exhumation, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, crustal-scale folding, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2012
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32. Inverse ductile thinning via lower crustal flow and fold-induced doming in the West Carpathian Eo-Alpine collisional wedge

Author: Petr, Jerabek, Lexa, O., Schulmann, Karel, Plasienka, Dusan, Schulmann, Karel, Institute of Petrology and Structural Geology (IPSG), Charles University [Prague] (CU), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Geology and Paleontology, Comenius University in Bratislava, and Czech Science Foundation GACR 205/09/1041
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDE.MCG] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes, [SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics
Abstract: International audience; Continental core complexes are generally interpreted to result from extensional doming due to gravity-driven upflow of lower crust. In contrast, the Vepor Dome is characterized by the lack of inverted density profile and relatively cold metamorphic field gradient which precludes an activation of Rayleigh-Taylor instability. Instead, the crustal structure of the Vepor Unit is marked by dense and weak metapelitic lower crust and light and strong granitoid upper crust inherited from Variscan nappe stacking. It is shown that the Cretaceous Eo-Alpine tectonic evolution of the Vepor Dome is controlled by the dynamics of two neighboring mechanically strong continental blocks, i.e., the overthrusting of the suprastructural Gemer Unit from the south and the underthrusting of the Fatric basement from the north. Structural, metamorphic and geochronological data from the Vepor Unit imply two main phases of the convergent process: (1) Lower Cretaceous crustal thickening due to overthrusting and internal deformation of the Gemer Unit together with upper crustal folding in the Vepor Unit led to the progressive development of the orogenic front parallel pressure gradient. The instantaneous response of the lower crustal and low-viscosity metapelites led to an along-strike lower crustal flow accompanied by prograde Barrovian-type metamorphism. (2) As the south vergent underthrusting of the Fatric basement propagated to greater depths during the Upper Cretaceous, the convergent process switched from top driven to bottom driven, and the exhumation of the lower crust occurred via polyharmonic folding. Overall doming of the Vepor Unit induced upper crustal detachment faulting and eastward unroofing of the dome.
Published: 2012

33. Microstructural and metamorphic evolution of a high pressure granitic orthogneiss during continental subduction (Sudetes, European Variscan belt)

Author: Chopin, F., Schulmann, Karel, Stipska, Pavla, Martelat, Jean-Emmanuel, Pitra, Pavel, Lexa, O., Petri, B., Dubigeon, Isabelle, Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Terre, Temps, Traçage, Géosciences Rennes (GR), 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), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-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), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Charles University [Prague] (CU), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), 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)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), and 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)
Subjects: [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, [SDU.STU.PE] Sciences of the Universe [physics]/Earth Sciences/Petrography, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2012

34. Variscan orogeny in Bohemian Massif and French Massif Central: differences and similarities

Author: Lardeaux, J, Schulmann, Karel, Faure, Michel, Lexa, O, Janoušek, V, Edel, J, ŠtÍpskÁ, P., Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and SCHOLASTIQUE, ELODIE
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, [SDU.STU.PE] Sciences of the Universe [physics]/Earth Sciences/Petrography, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2012

35. Tectono-metamorphic history recorded in garnet porphyroblasts: insights from thermodynamic modelling and electron backscatter diffraction analysis of inclusion trails

Author: Skrzypek, E., Schulmann, K., ŠtÍpskÁ, P., Chopin, F., Lehmann, J., Lexa, O., Haloda, J., Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Charles University [Prague] (CU), Ecole et Observatoire des Sciences de la Terre (EOST), and Schulmann, Karel
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDE.MCG] Environmental Sciences/Global Changes, [SDE.MCG]Environmental Sciences/Global Changes, [SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; In a Barrovian metamorphic sequence, garnetiferous mica schists document a heterogeneously developed superposition of sub-orthogonal fabrics and multiple garnet growth episodes. In the variably deformed domains, four types of garnet porphyroblasts have been defined based on inclusion trail patterns. Modelled garnet zoning in the MnNCKFMASHTO system indicates a prograde evolution from 4-4.5 kbar and 490-510 C to 5-6 kbar and 520-550 C in the earliest subhorizontal fabric progressing towards 6.5-7.5 kbar and 560-590 C in the subsequent subvertical foliation. This fabric is heterogeneously deformed into a shallow-dipping retrograde foliation associated with garnet resorption. In situ electron backscatter diffraction measurements of ilmenite inclusions in individual garnet grains yield precise data on included planar and linear elements. Consistent orientations of internal foliations, lineations and foliation intersection axis sets indicate a superposition of three sub-orthogonal foliation systems. Weak variations of internal records with increasing intensity of deformation suggest that a moderate buckling stage occurred, but apparent lack of porphyroblast rotation is interpreted as a result of dominant passive flow. Coupling the orientation of internal fabric sets with P-T estimates is used to complement the tectono-metamorphic evolution of the thickened crust. We demonstrate that garnet porphyroblasts preserve features which reflect large-scale tectonic processes in orogens.
Published: 2011
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36. A geophysical model of the Variscan orogenic root (Bohemian Massif): Implications for modern collisional orogens

Author: Guy, Alexandra, Edel, J.B., Schulmann, Karel, Tomek, Cestmir, Lexa, O., Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Charles University [Prague] (CU), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and ANR-06-BLAN-0352,LFO in orogens,Laterally-forced overturns (LFO) enhanced by melt induced softening (MIS) in orogens: new model for continental tectonics(2006)
Subjects: Bohemian Massif, [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, Variscan Orogeny, Felsic orogenic lower crust, Seismic profiles, [SDE.MCG]Environmental Sciences/Global Changes, Continental indentation, Gravimetric model
Abstract: International audience; A new model of the structure and composition of the Variscan crust in the Bohemian Massif is proposed based on 3D gravity modelling, geological data, seismic refraction (CEL09) and reflection (9HR) sections. The Bohemian Massif crust is characterized by a succession of positive and negative anomalies of about 6080 km wavelength for nearly constant Moho depths. The south-western part of the Bohemian Massif displays a large negative Bouguer anomaly corresponding to high grade rocks (granulites and migmatites) of the Palaeozoic crustal root represented by the Moldanubian domain. The adjacent Neo-Proterozoic Bruno-Vistulian microcontinent displays an important gravity high reflecting mafic and intermediate medium grade metamorphic and magmatic rocks. The deep crustal boundary between the root domain and the Bruno-Vistulian microcontinent is represented by a strong gradient located 50 to 70 km westwards from the surface boundary between these units indicating that the high density basement rocks are covered by a thin sheet of low density granulites and migmatites. North-west from the Moldanubian domain occurs an important gravity high corresponding to the Neo-Proterozoic basement of the Tepla-Barrandian Unit limited in the north by southeast dipping reflectors of the Tepla suture which is characterized by high density eclogites and ultramafics. The footwall of the suture corresponds to low density felsic crust of the Saxothuringian basement. The reflection and refraction seismics and gravity modelling suggest a complex lithological structure of the Moldanubian domain marked by a low density 5-10 km thick lower crustal layer located above the Moho, a 5-10 km thick heavy mafic layer, a 10 km thick mid-crustal layer of intermediate density and a locally developed 2-5 km thick low density layer at the surface. The low density lower crust correlates well with low P-wave velocities in the range 6.0-6.4 km s(-1) in the CEL09 section. This complex geophysical structure and surface geology are interpreted as a result of Carboniferous partial overturn of low density lower crust and high and intermediate density crust in the area of central root and by viscous extrusion of low density orogenic lower crust over the high density Bruno-Vistulian continent. Comparison of these data with geophysical profiling of the Andean and the Tibetan plateaus suggests that modern orogenic systems reveal comparable deep crustal geophysical pattern. Based on these similarities we propose that the Variscan root represents a deep crustal section of above mentioned plateaus, which may have develop by the same orogenic process. (C) 2010 Elsevier B.V. All rights reserved.
Published: 2011
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37. Prograde and retrograde metamorphic fabrics - a key for understanding burial and exhumation in orogens (Bohemian Massif)

Author: Skrzypek, E., ŠtÍpskÁ, P., Schulmann, Karel, Lexa, O, Lexová, M, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Charles University [Prague] (CU), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), ANR-06-BLAN-0352,LFO in orogens,Laterally-forced overturns (LFO) enhanced by melt induced softening (MIS) in orogens: new model for continental tectonics(2006), and Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Bohemian Massif, burial and exhumation, [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, P-T-D path, [SDE.MCG]Environmental Sciences/Global Changes, [SDU.STU.PE]Sciences of the Universe [physics]/Earth Sciences/Petrography, prograde and retrograde fabrics, P-T pseudosection, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; In the Orlica-Snieznik Dome (NE Bohemian massif), alternating belts of orthogneiss with high-pressure rocks and belts of mid-crustal metasedimentary-metavolcanic rocks commonly display a dominant subvertical fabric deformed into a subhorizontal foliation. The first macroscopic foliation is subvertical, strikes NE-SW and is heterogeneously folded by open to isoclinal folds with subhorizontal axial planes parallel to the heterogeneously developed flat-lying foliation. The metamorphic evolution of the mid-crustal metasedimentary rocks involved successive crystallization of chlorite-muscovite-ilmenite-plagioclase-garnet, followed by staurolite-bearing and then kyanite-bearing assemblages in the subvertical fabric. This was followed by garnet retrogression, with syntectonic crystallization of sillimanite and andalusite parallel to the shallow-dipping foliation. Elsewhere, andalusite and cordierite statically overgrew the flat-lying fabric. With reference to a P-T pseudosection for a representative sample, the prograde succession of mineral assemblages and the garnet zoning pattern with decreasing grossular, spessartine and X-Fe are compatible with a P-T path from 3.5-5 kbar/490-520 degrees C to peak conditions of 6-7 kbar/similar to 630 degrees C suggesting burial from 12 to 25 km with increasing temperature. Using the same pseudosection, the retrograde succession of minerals shows decompression to sillimanite stability at similar to 4 kbar/similar to 630 degrees C and to andalusite-cordierite stability at 2-3 kbar indicating exhumation from 25 km to around 9-12 km. Subsequent exhumation to similar to 6 km occurred without apparent formation of a deformation fabric. The structure and petrology together with the spatial distribution of the metasedimentary-metavolcanic rocks, and gneissic and high-pressure belts are compatible with a model of burial of limited parts of the upper and middle crust in narrow cusp-like synclines, synchronous with the exhumation of orogenic lower crust represented by the gneissic and high-pressure rocks in lobe-shaped and volumetrically more important anticlines. Converging P-T-D paths for the metasedimentary rocks and the adjacent high-pressure rocks are due to vertical exchanges between cold and hot vertically moving masses. Finally, the retrograde shallow-dipping fabric affects both the metasedimentary-metavolcanic rocks and the gneissic and high-pressure rocks, and indicates that the similar to 15-km exhumation was mostly accommodated by heterogeneous ductile thinning associated with unroofing of a buoyant crustal root.
Published: 2011
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38. Heat sources and trigger mechanisms of exhumation of HP granulites in Variscan orogenic root

Author: Lexa, O., Schulmann, Karel, Janousek, V., ŠtÍpskÁ, P., Guy, Alexandra, Racek, Martin, Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Charles University [Prague] (CU), Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Petrology and Structural Geology (IPSG), and ANR-06-BLAN-0352,LFO in orogens,Laterally-forced overturns (LFO) enhanced by melt induced softening (MIS) in orogens: new model for continental tectonics(2006)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, heat sources, [SDE.MCG]Environmental Sciences/Global Changes, exhumation of lower crust, radioactive heating, crustal structure
Abstract: International audience; The structure of the Moldanubian domain is marked by felsic granulites of Ordovician protolith age forming the cores of domes that are separated from mid-crustal Neoproterozoic and Palaeozoic metasedimentary rocks that occur in synclines by a late Ordovician to Silurian metabasic unit. Reflection and refraction seismic sections combined with gravity inversion modelling suggest the presence of a low density layer at the bottom of the crust (interpreted as felsic granulite) overlain by a denser layer (interpreted as amphibolite) with layers of intermediate density at the top (interpreted as metasedimentary rocks). It is proposed that the granulite domes surrounded by middle crustal rocks reflect transposed horizontal layering originally similar to that preserved in the deep crust and imaged by the geophysical surveys. This geological and geophysical structure is considered to be a result of Visean gravity redistribution initiated by radioactive heating of felsic crust tectonically emplaced at the bottom of a Palaeozoic orogenic root. The radioactive layer with heat production of 4 mu W m-3 corresponds geochemically and isotopically to Ordovician felsic metaigneous rocks of the Saxothuringian domain that have been emplaced at Moho depth under thickened crust during late Devonian-early Carboniferous continental subduction. Part of the continental crust continued to be subducted and produced fluids/low-volume melts which directly contaminated and enriched the local lithospheric mantle by lithophile elements, most notably Cs, Rb, Li, Pb, U, Th and K. Thermal incubation of 10-15 Myr was sufficient to heat and convert the underplated felsic layer into granulites via dehydration melting and melt segregation. The process of melt loss was responsible for the removal of radioactive elements and for switching off the heat at the beginning of the exhumation process. At the same time, the metasomatized underlying mantle was heated producing characteristic ultrapotassic magmas. Gravitational instability was then induced by the density contrast between the light granulites and the overlaying denser mafic lower crustal layer and a viscosity drop related to thermal weakening and partial melting of the latter.
Published: 2011
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39. Origin of felsic granulite microstructure by heterogeneous decomposition of alkali feldspar and extreme weakening of orogenic lower crust during the Variscan orogeny

Author: Franek, J., Schulmann, Karel, Lexa, O., Ulrich, Stanislav, Štípska, P., Haloda, J., Tycova, P., Czech Geological Survey [Praha], Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Petrology and Structural geology, Charles University [Prague] (CU), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Geophysics of the Czech Academy of Sciences (IG / CAS), Czech Academy of Sciences [Prague] (CAS), and ANR-06-BLAN-0352,LFO in orogens,Laterally-forced overturns (LFO) enhanced by melt induced softening (MIS) in orogens: new model for continental tectonics(2006)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, Moldanubian domain, quantitative microstructural analysis, [SDE.MCG]Environmental Sciences/Global Changes, felsic granulites, Variscan belt, quartz and feldspar rheology
Abstract: International audience; This study answers the question of origin and evolution of a granulitic microstructure typically developed in felsic granulites of the European Variscan belt. It shows that the precursor of the Variscan felsic granulites was a high-pressure alkali feldspar-rich coarse-grained layered orthogneiss. Its S1 subhorizontal layering is defined by the alignment of alkali feldspar porphyroclasts alternating with monomineralic bands of quartz and bands rich in plagioclase and garnet. The alkali feldspar porphyroclasts contain inclusions of quartz, garnet, kyanite, biotite and rutile, reflecting peak P-T conditions of 1.6-1.8 GPa and 850 degrees C during S1 formation. Superimposed steep folds and steep cleavage, S2, are associated with recrystallization of alkali feldspar, plagioclase and quartz, and garnet chemistry modifications that correspond to 0.9-1.0 GPa and 800 degrees C. During exhumation, involving 0.8 GPa decompression and cooling, the probably perthitic alkali feldspar underwent an unusual process of heterogeneous decomposition along irregular reaction fronts forming a fine-grained matrix composed of plagioclase and K-feldspar grains. Regular grain distributions in the matrix, nucleation-dominated crystal size distribution and preservation of lattice orientation of the parental perthite crystals are all explained by a discontinuous precipitation process. This heterogeneous decomposition of alkali feldspar solid solution is controlled by chemically and strain induced grain-boundary migration. During exhumation and decompression, the fine-grained matrix underwent viscous deformation, forming the typical microstructure of the Variscan granulites. Random phase distributions, minor coarsening and feldspar textures are interpreted as a result of strain softening due to diffusion creep-accommodated grain-boundary sliding. Subordinate large quartz ribbons were rheologically stronger than the feldspar-dominated matrix due to the activity of different deformational mechanisms. Finally, in mid-crustal levels, the subvertical structure was overprinted by a perpendicular steep fabric associated with the growth of sillimanite, heterogeneous hydration and local partial melting, development of aggregate phase distributions and significant coarsening. This evolution is accompanied with the development of a strong lattice preferred orientation of quartz, K-feldspar and plagioclase, reflecting a switch to dislocation creep mechanism and a general hardening of the granulites under amphibolite facies conditions.
Published: 2011
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40. Model of syn-convergent extrusion of orogenic lower crust in the core of the Variscan belt: implications for exhumation of high-pressure rocks in large hot orogens

Author: Franek, Jan, Schulmann, Karel, Lexa, O., Tomek, Cestmir, Edel, J.B., Czech Geological Survey [Praha], Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Petrology and Structural geology, Charles University [Prague] (CU), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and ANR-06-BLAN-0352,LFO in orogens,Laterally-forced overturns (LFO) enhanced by melt induced softening (MIS) in orogens: new model for continental tectonics(2006)
Subjects: [SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics, Moldanubian domain, [SDE.MCG]Environmental Sciences/Global Changes, exhumation, granulites, Variscan belt, orogenic lower crust
Abstract: International audience; Reflection seismic section, field structural analysis and gravimetric modelling of orogenic lower crust in the core of a Carboniferous orogenic root reveal details of the polyphase process of exhumation. Subvertical amphibolite facies fabrics strike parallel to former plate margins that collided in the NW. The fabrics are developed in both mid-crustal and lower crustal high-pressure granulite units as a result of intensive NW-SE intraroot horizontal shortening driven probably by the west-directed collision. In granulites, the steep fabrics originated as a result of extrusion of orogenic lower crust in a similar to 20 km wide vertical ascent channel from lower crustal depths at 350-340 Ma. The large granulite bodies preserve older granulite facies fabrics documenting a two-stage evolution during the exhumation process. Surface exposures of granulites coincide with the absence of subhorizontal seismic reflectors at depth, suggesting preservation of the similar to 20 km wide subvertical tabular structure reaching Moho depths. Horizontal seismic reflectors surrounding the vertical channel structure corroborate a dominant flat migmatitic fabric developed in all tectonic units. This structural pattern is interpreted in terms of subhorizontal spreading of partially molten orogenic lower crust in mid-crustal levels (765 degrees C and 0.76 GPa) at 342-337 Ma. Large massifs of extruded and progressively dismembered felsic granulites disturbed mid-crustal fabrics in the surrounding horizontally flowing partially molten crust. The horizontal mid-crustal flow resulted in collapse of the supra-crustal Tepla-Barrandian Unit (interpreted as the orogenic lid) along a large-scale crustal detachment above the extruded lower crustal dome. The presence of felsic granulites at the bottom of the orogenic root is considered to be a key factor controlling the exhumation of orogenic lower crust in large hot orogens.
Published: 2011
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41. Early Cambrian eclogites in SW Mongolia: evidence that the Palaeo-Asian Ocean suture extends further east than expected

Author: ŠtÍpskÁ, P., Schulmann, K., Lehmann, J., Corsini, M., Lexa, O., Tomurhuu, D., Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institute of Petrology and Structural geology, Charles University [Prague] (CU), Czech Geological Survey [Praha], Institute of Geology and Mineral Resources, Mongolian Academy of Sciences (MAS), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), and Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: International audience; Newly discovered eclogites, Early Cambrian carbonates and chloritoid-bearing metapelites form the Tsakhir Uul accretionary wedge, which was thrust during the Early Cambrian over the Mesoproterozoic Dzabkhan-Baydrag continent. The rock association of the wedge forms a tectonic window emerging through the hangingwall Khantaishir ophiolite unit, which preserves a typical Tethyan-type ophiolitic sequence. The eclogites correspond geochemically to T-MORB modified by fluid circulation. They are composed of garnet, omphacite, amphibole, rutile ±muscovite ±quartz ±epidote and exhibit well-equilibrated matrix textures. Jadeite content of the omphacite reaches up to 45 mol.%, the Si content of muscovite is between 3.40 and 3.45 p.f.u., amphibole is winchite to barroisite, but reaches tschermakitic composition at some rims, and garnet composition is grs0.24–0.36, alm0.43–0.56, py0.05–0.18, sps0.00–0.18, inline image. The peak assemblage, together with the composition of garnet rims, omphacite, amphibole and muscovite, correspond in a pseudosection to 20−22.5 kbar and 590−610 °C. The tschermakitic rim of amphibole is interpreted as partial reequilibration on decompression below 16 kbar and ∼600−630 °C. Two muscovite separates from the eclogite yielded an Ar–Ar plateau age of 543.1 ± 3.9 Ma (1σ) and a mean age of 547.9 ± 2.6 Ma (1σ), whereas muscovite from an interbedded garnet-chloritoid micaschist yielded an Ar–Ar plateau age of 536.9 ± 2.7 Ma (1σ); these ages are interpreted as cooling ages. The P–T data, geochemistry of eclogites and cooling ages suggest an affinity between the Tsakhir Uul wedge and the Gorny Altai and the north Mongolian blueschist belt, which are believed typical for subduction of warm oceanic lithosphere and closure of small oceanic basins. Thus, the discovery of the Tsakhir Uul eclogites represents an important finding suggesting extension of the Early Cambrian subduction system of the Central Asian Orogenic Belt far to the east in a region where it was not expected.
Published: 2010
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42. Repeated slip along a major decoupling horizon between crustal-scale nappes of the Central Western Carpathians documented in the Ochtiná tectonic mélange

Author: Novotná, N., primary, Jeřábek, P., additional, Pitra, P., additional, Lexa, O., additional, and Racek, M., additional
Published: 2015
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43. P-T-t-D record of crustal-scale horizontal flow and magma-assisted doming in the SW Mongolian Altai

Author: Broussolle, A., primary, Štípská, P., additional, Lehmann, J., additional, Schulmann, K., additional, Hacker, B. R., additional, Holder, R., additional, Kylander-Clark, A. R. C., additional, Hanžl, P., additional, Racek, M., additional, Hasalová, P., additional, Lexa, O., additional, Hrdličková, K., additional, and Buriánek, D., additional
Published: 2015
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44. An Andean type Palaeozoic convergence in the Bohemian Massif - Convergence paléozoïque de type Andin dans le Massif de Bohême

Author: Schulmann, K., KonopÁsek, J., Janousek, V., Lexa, O., Lardeaux, J.M., Edel, J.B., ŠtÍpskÁ, P., Ulrich, S., Ecole et Observatoire des Sciences de la Terre (EOST), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Czech Geological Survey [Praha], Institute of Petrology and Structural geology, Charles University [Prague] (CU), Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institute of Geophysics of the Czech Academy of Sciences (IG / CAS), Czech Academy of Sciences [Prague] (CAS), Czech Geological Survey, Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), and Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: International audience; The geological inventory of the Variscan Bohemian Massif can be summarized as a result of Early Devonian subduction of the Saxothuringian ocean of unknown size underneath the eastern continental plate represented by the present-day Teplá-Barrandian and Moldanubian domains. During mid-Devonian, the Saxothuringian passive margin sequences and relics of Ordovician oceanic crust have been obducted over the Saxothuringian basement in conjunction with extrusion of the Teplá-Barrandian middle crust along the so-called Teplá suture zone. This event was connected with the development of the magmatic arc further east, together with a fore-arc basin on the Teplá-Barrandian crust. The back-arc region – the future Moldanubian zone – was affected by lithospheric thinning which marginally affected also the eastern Brunia continental crust. The subduction stage was followed by a collisional event caused by the arrival of the Saxothuringian continental crust that was associated with crustal thickening and the development of the orogenic root system in the magmatic arc and back-arc region of the orogen. The thickening was associated with depression of the Moho and the flux of the Saxothuringian felsic crust into the root area. Originally subhorizontal anisotropy in the root zone was subsequently folded by crustal-scale cusp folds in front of the Brunia backstop. During the Visean, the Brunia continent indented the thickened crustal root, resulting in the root's massive shortening causing vertical extrusion of the orogenic lower crust, which changed to a horizontal viscous channel flow of extruded lower crustal material in the mid- to supra-crustal levels. Hot orogenic lower crustal rocks were extruded: (1) in a narrow channel parallel to the former Teplá suture surface; (2) in the central part of the root zone in the form of large scale antiformal structure; and (3) in form of hot fold nappe over the Brunia promontory, where it produced Barrovian metamorphism and subsequent imbrications of its upper part. The extruded deeper parts of the orogenic root reached the surface, which soon thereafter resulted in the sedimentation of lower-crustal rocks pebbles in the thick foreland Culm basin on the stable part of the Brunia continent. Finally, during the Westfalian, the foreland Culm wedge was involved into imbricated nappe stack together with basement and orogenic channel flow nappes.
Published: 2009
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45. Vertical extrusion and horizontal spreading of orogenic lower crust: a key exhumation mechanism in large hot orogens?

Author: Schulmann, K., Lexa, O., Štipska, P., Racek, M., Tajcmanova, L., Konopasek, J., Edel, J.-B., Peschler, A., Lehmann, J., Centre de géochimie de la surface (CGS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2008
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46. Origin of migmatites by deformation-enhanced melt infiltration of orthogneiss: a new model based on quantitative microstructural analysis

Author: Hasalova, P., Schulmann, K., Lexa, O., Stipska, P., Hrouda, F., Ulrich, S., Haloda, J., Tycova, P., Centre de géochimie de la surface (CGS), Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Institut national des sciences de l'Univers (INSU - CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)
Subjects: ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2008
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47. Electrocardiographic isopotential exercise and oesophageal stimulation maps in the diagnosis of myocardial ischaemia

Author: Janota, M, primary, Bytesnik, J., additional, Lexa, O., additional, and Stupka, J., additional
Published: 1988
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48. The mode of flow and emplacement of a trachyte body of the české středohoří mts. Studied by means of AMS and EBSD techniques

Author: Zavada, P., Schulmann, K., Lexa, O., Hrouda, F., Haloda, J., Tycova, P., Smid, J., Aunis, Danièle, Centre de géochimie de la surface (CGS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Institut national des sciences de l'Univers (INSU - CNRS)
Published: 2006

49. Cretaceous age of quartz-stibnite veins near Cucma (Spissko-gemerské rudohorie Mts.) (in slowakischer Sprache)

Author: Hurai, V., Urban, M., Konecny, P., Thomas, R., Lexa, O., Schulmann, K., and Chovan, M.
Published: 2006

50. Deformation pattern related to an orogen parallel extension event recorded in the vepor unit, West Carpathians

Author: Jerabek, P., Schulmann, K., Lexa, O., Faryad, W., Heilbronner, R., Stuenitz, H., Centre de géochimie de la surface (CGS), Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Institut national des sciences de l'Univers (INSU - CNRS), Aunis, Danièle, and Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)
Published: 2006

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