Análisis dinámico del sistema de desgarres NO-SE del Prebético de Albacete

Abstract

The NW-SE dextral strike-slip faults in the External Prebetic (Albacete province) constitute the eastern transfer zone related to the emplacement of the Cazorla Are, characterized by a system of imbricated thrusts, throughout the Early-Middle Miocene. The study area is traversed by three main strike-slip faults (Socovos-Calasparra, Liétor and Pozohondo) which delimit two areas with an anomalous E-W to WNW-ESE fold trend with regard to the NE-SW betic fold trend. A radial extensional tectonics began in the Upper Miocene and E-W normal faults were developed. A microstructural analysis has been carried out from small-scale striated fault planes measured in sedimentary rocks from Mesozoic to Quaternary age as well as in Late Miocene volcanic rocks. Three stress fields have been determined: 1st stress field (σHMAX NO 18ºE), 2nd stress field (Radial extensional tectonics) and 3rd stress field (σHMAX N149ºE). The first stress field, which caused the E-W thrusts and folds, is a local deviation of the regional betic compression related to a dextral transpressive zone. The second stress field reflects the post-Serravallian extensional tectonics and represents a local situation in the regional geodynamic context (convergence between African and Eurasian plates). The third stress field shows the build-up of the Cazorla Arc and the recovery of the regional stress trajectories.