International audience
International audience
The recognition of a fossil equivalent of the active geothermal system of the Basse-Terre Island in Guadeloupe archipelago (Lesser Antilles arc) in Terre-de-Haut Island (Les Saintes archipelago) allow us to better constrain the structure, the mineralogy and the petrological characters of the deep parts of an active geothermal reservoir. First,...
We unravel for the first time the expression of a low-grade metamorphic event affecting the deepest exposures of the Guadeloupe Island, central Lesser Antilles, Caribbean plate. The work offers a novel insight for the presence of young (<3 Ma) sub-greenschist facies metamorphism in the Lesser Antilles active arc and is consistent with the...
We investigate the potential of 40Ar-39Ar systematics in secondary K-bearing minerals developed at the expense of hydrothermally altered volcanic pyroxenes from a fossil geothermal system located in the Saintes archipelago (Lesser Antilles magmatic arc).Our work reports the first example of dating hydrothermal muscovite crystallization...
The Sidi El Hemissi region, Souk-Ahras, is part of the Tellian Atlas where the Triassic sediments tectonically outcrop under the Tellian nappes of the Maghrebide chain. Mafic rocks, mainly gabbros and dolerites, called "ophites," are interbedded as a ~ 200 × 30-m lenticular body within the Triassic gypsum-rich formation. These rocks show...
Les résultats de datation multiméthodes de trois sites archéologiques sont présentés : ceux d'Orgnac 3 (Ardèche, France), de la grotte du Lazaret (Alpes-Maritimes, France) et de la grotte de Zafarraya (Andalousie, Espagne). Les sites ont été datés par les méthodes 40Ar/39Ar, U-Th et/ou 14C. À Orgnac 3 où on trouve Homo heidelbergensis et...
The identification of a large OIB-type volcanic sequence on top of an obducted nappe in the Lesser Caucaus of Armenia helps us explain the obduction processes in the Caucasus region that are related to dramatic change in the global tectonics of the Tethyan region in the late Lower Cretaceous. The ophiolitic nappe preserves three distinct...