A càrrec de: Dr. Jonas Ruh Institut de Ciències de la Terra Jaume Almera
Thin-skinned fold-and-thrust belts related to convergence tectonics develop by scraping off a rock sequence along a weaker basal décollement often formed by water-saturated shale layers or low-viscosity salt horizons. Numerical models with sophisticated rheologies are used to investigate the structural evolution of fold-and-thrust belts overlying different types of décollements. In addition, the effect of the strength of shear zones within such fold-and-thrust belts is investigated. Shear zones are usually weaker than surrounding rocks, but whether weakening depends on accumulated strain or strain rate is still a matter of debate. Aside rheological effect, geometrical constraints have a large influence on the structural evolution of fold-and-thrust belts. For example, seamounts entering active subduction zone trenches initially collide with the frontal sedimentary accretionary wedges resulting in severe deformation of the overriding plate. A typical feature of this deformation is the occurrence of submarine landslides due to gravitational instabilities. 3D numerical models are applied to infer deformation patterns and stress distribution within the upper plate during seamount subduction.

Dia: Dimarts 26 d'abril
Hora: 12:00 h
Lloc: Sala d'actes de l'Institut Jaume Almera