GUILLOT , Stéphane

New fission-track ages on zircon and apatite (ZFT and AFT) from the southwestern alpine paleo-accretionary wedge document a contrasting cooling history from east to west. In the eclogitic Monviso ophiolites, the ZFT ages are 19.6 +/- 0.8 Ma and the AFT ages are 8.6 +/- 1.7 Ma. In the HT-blueschist eastern Queyras, ZFT ages range from 27.0 +/-...

his paper addresses the contribution of extension in the upper crust during syncollisional exhumation of subducted material. We present structural data based on the analysis of ductile, brittle-ductile, and brittle deformation features in metapelitic schists and meta-basalts from the Schistes lustrés nappe stack in the Piedmont zone of the...

A geotransect from the Pelvoux Massif (external French Alps) to the Dora-Maira massif (internal Italian Alps), through the Monviso ophiolitic complex was investigated in the framework of a geological and geophysical imagery program of the continental crust: "Géo-France 3D Alpes". In this paper we present and discuss a new interpretative...

The 1000 km-long suture zone of the Dahomeyide belt, exposed from Southeast Ghana to South Mali, corresponds to a narrow and lithologically diverse area with symptomatic coronitic HP granulitic massifs. Based on a review of published petrological, geochemical and geochronological data along the Dahomeyide belt we propose a global scenario for...

The exhumation of subducted lithosphere requires a mechanically weak zone at the interface between the subduction plane and the rigid overlying mantle peridotites with a viscosity greater than 10 20 Pa.s. At shallow depths (< 40-50 km) blueschists are exhumed in accretionary wedge along the interface between the subducting plate and the...

Amphiboles and a biotite from amphibolites and amphibolitic gneisses of the Karakorum Metamorphic Complex (KMC, NW Himalaya), were dated using the 40Ar/39Ar method. Isotope correlations were compared to electron-microprobe analyses. Both AlIV and AlVI contents of amphibole increase from the south near the Shyok Suture Zone to the Dassu-Askole...

In the South Tien Shan range (Kyrgyzstan), the Late Paleozoic geodynamic evolution remains debated especially to the west of the Talas-Fergana fault (TFF) fault where suture-related high-pressure (HP) rocks are scarce. We provide new petrological and geochronological data on garnet amphibolites from the Chatkal range, to the west of the TFF,...

Lithological and structural maps from the East Commonwealth Bay Unit (ECB; Terre Adélie and Georges V land, Antarctica) are presented with a summary of the main structural and metamorphic data obtained in the area. The ECB unit is structured during the Late Archean – Lower Proterozoic (at 2.4-2.5 Ga), with (i) granulite metamorphism at 9 - 6...

The tectonic evolution of the Central Asian Orogenic Belt (CAOB) is characterized by the successive accretion of lithospheric blocks, leading to different interpretations about the polarity of subductions during the Paleozoic, the number of microplates and oceanic basins and the timing of tectonic events. This is especially the case in the Tien...

The South Tien Shan (STS) belt results from the last collision event in the western Central Asian Orogenic Belt (CAOB). Understanding its formation is of prime importance in the general framework of the CAOB. The Atbashi Range preserves high‐P (HP) rocks along the STS suture, but still, its global metamorphic evolution remains poorly...

The Permian history of the Central Asian Orogenic belt is marked by large-scale strike-slip faults that reactivate former Paleozoic structures, delineated by widespread alkaline magmatism. The genetic link between the syn-kinematic granitoids emplaced in the Tien Shan range and magmas emplaced within the Tarim Large Igneous Province, and the...