Detall
SEMINARIS DE LA FACULTAT DE GEOLOGIA I L'INSTITUT DE CIÈNCIES DE LA TERRA 'JAUME ALMERA':"Mio-Pliocene orogenic plateau building in the Arabia-Eurasia collision zone, Iran: outward expansion to incision and excavation"
Dr. Paolo Ballato (Institute of Earth and Environmental Science, Universitat de Potsdam, Alemanya)
Located along convergent margins, high orogenic plateaus form extensive low-relief morphotectonic provinces that are flanked by high mountain ranges. The NW-SE oriented Iranian Plateau (IP) is a prominent, elevated, mostly internally drained, and arid region, virtually aseismic and characterized by thick crust (70km) and lithosphere (260 km). Very little is known about the IP tectono-stratigraphic history and the mechanisms and timing of vertical and lateral plateau-growth after the deposition of marine carbonate at ~17Ma. These questions are addressed by characterizing depositional environments, provenance, magnetostratigraphy and geochronology of synorogenic deposits and subsequent correlation with the exhumation history of the surrounding mountain.
Sedimentation in the northern IP took place in a contiguous foreland-basin system, most likely triggered by thrust loading from ~16.5 Ma. Late Miocene (<10.7 Ma) widespread rock uplift excised parts of the foreland, incorporating new intermontane basin sectors into the orogenic plateau and compartmentalizing the foreland into a contractional basin-and-range topography. These findings suggest that the northern sectors of the IP developed during crustal shortening and thickening processes rather than whole scale surface uplift during mantle delamination. Our new results also document that sometime after 10.7 Ma the northern IP had already reached a lateral extent and basin geometries that were similar to the modern conditions.
Data: 14-10-2015
Hora: 12:00
LLoc: Sala d'actes de l'Institut de Ciències de la Terra Jaume Almera
Organització: Organitzat conjuntament CSIC-UB