Cronología extendida en depósitos aluviales mediante luminiscencia estimulada por luz violeta (VSL) en el SE de la Península Ibérica

Abstract

Luminescence dating has become a key tool in active tectonics studies. In this work, focused on the Eastern Betics Shear Zone (SE Spain), the chronological record exceeds the age range that can be covered with conventional methods of OSL (Optical Stimulated Luminescence) dating. The sediments sampled have been dated using VSL (Violet Stimulated Luminescence) which has the potential to extend the age range covered, since the VSL signal saturates at higher doses than conventional OSL which uses blue or green stimulation (Jain 2009; Ankjӕrgaard et al. 2013). With this new technique, doses of up to 400 Gy, twice the saturation dose of standard OSL, have been estimated. This has made it possible to provide an extended chronology for the studied stratigraphic profile, establishing the time sequence of tectonic activity in the study area between 60 and 300 ka. This study presents the first estimated ages based on VSL of alluvial fans and confirms the suitability of the method for active tectonics studies in the SE of the Iberian Peninsula. It opens up the possibility of extending the age estimation for alluvial sequences, which would help to improve the slip rate estimation of active faults and particularly the ones of slowest rates.