Manioc : Portail | resultats 1 - 20 pour la recherche: Schy, T.

Flora brasiliensis : enumeratio plantarum in Brasilia hactenus detectarum quas suis aliorumque botanicorum studiis descriptas et methodo naturali digestas partim icone illustratas. Volumen XI, Pars II, Euphorbiaceae
Auteur(s) : Müller, Joannes
Auteurs secondaires : Martius, Karl Friedrich Philipp von (1794-1868) Eichler, August Wilhelm (1837-1887)
Année de publication :

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La géologie et les mines de la France d'outre-mer : recueil de conférences
Auteurs secondaires : Lacroix, Alfred (1863-1948) Bureau d'études géologiques et minières (France)
Année de publication :

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Rapport sur les questions coloniales adressé à M. le duc de Broglie,... à la suite d'un voyage fait aux Antilles et aux Guyanes pendant les années 1838 et 1839. Tome II, Documents et pièces justificatives. Deuxième partie, Etude de l'émancipation dans les colonies anglaises depuis l'année 1833 jusqu'au 3 décembre 1842
Auteur(s) : Lechevalier Saint-André, Jules (1806-1862)
Année de publication :

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British Virgin Islands ( Mount Healthy Sugar Plantation, Tortola )
Auteur(s) : Caribbean Volunteer Expeditions Hersh, A. Schy, T.

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La Guadeloupe. Renseignements sur l'Histoire, la Flore, la Faune, la Géologie, la Minéralogie, l'Agriculture, le Commerce, l'Industrie, la Législation, l'Administration. Tome Ier : 1625-1715
Auteur(s) : Ballet, Jules (1825-1904)
Année de publication :

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Metamorphic and age constraints on the Alakeci shear zone: Implications for the extensional exhumation history of the northern Kazdag Massif, NW Turkey
Auteur(s) : Bonev, Nikolay Beccaletto, Laurent Robyr, Martin Monie, Patrick
Auteurs secondaires : Department of Geology and Paleontology, Sofia University ; Université du Québec Bureau de Recherches Géologiques et Minières (BRGM) (BRGM) Department of Geodynamics and Sedimentology, University of Vienna, ; Université du Québec Géosciences Montpellier ; Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS)

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The Kazdag Massif exposes an extensional metamorphic dome in the Biga Peninsula of northwest Turkey, bounded on both flanks by detachments and/or shear zones. The northern flank is marked by the extensional Alakeci shear zone (ASZ), with poorly known P-T-t path. We therefore focus on metamorphic conditions and temporal history of the ASZ to determine its tectono-metamorphic evolution. ASZ mylonites were derived from both the footwall Kazdag Massif core metamorphic rocks and the hanging wall Cetmi melange lithologies. The mylonitic fabrics in the ASZ depict a top-to-the NNE shearing, parallel to the NNE-plunging stretching lineation and NNW-dipping mylonitic foliation. This geometry implies normal sense movement i.e. north-side down-dip extensional displacement along this flank of the Kazdag Massif. The northward transition from ductile to brittle-ductile shear regime through the ASZ shows that the non-coaxial deformation occurred at decreasing temperatures and degree of metamorphism. The paragenesis in equilibrium of the mylonitic gneisses and schists contains quartz + feldspar + muscovite + biotite + garnet staurolite, with late retrogressive chlorite after biotite and garnet. Calculated thermo-barometric conditions for ASZ rocks yielded pressures between 6.9 and 5.7 kbar and temperatures between 706 and 587 degrees C, which constrain the peak metamorphism. The mylonitic rocks supplied isochron Ar-39/Ar-40 mica ages between 26.97 and 24.19 Ma, which we interpret to date the cooling of the mylonites following the P-T decrease across the ASZ. The metamorphic data support the structural record and strengthen the extensional character of the ASZ. The transition from sillimanite-bearing footwall Kazdag Massif core gneisses in the deeper structural levels to chlorite schists; towards the shallow structural levels at the top of the ASZ, is consistent with an extensional exhumation of the metamorphic pile. These data allow us to determine the peak P-T conditions and the temporal evolution in the northern flank of the Kazdag Massif, where Late Oligocene extensional exhumation was assisted by NNE-directed ductile-brittle ASZ, which had operated from amphibolite to greenschist facies. The ASZ, together with similar time-constrained ductile-brittle activity of SW-directed detachment along the southern flank of the massif, collectively indicates a bivergent mode of extension in the western Kazdag Massif. The latter is likely influenced by magmatic activity spatially and temporally related to these extensional zones. At the regional scale, the bivergent tectono-metamorphic pattern of the Kazdag Massif is similar to those observed on other places of the north-central Aegean domain.
ISSN: 0024-4937

hal-00445246
https://hal.archives-ouvertes.fr/hal-00445246
DOI : 10.1016/j.lithos.2009.02.010

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