Palaeoseismological record of the active Galera Fault (Central Betic Cordillera, Spain)

Abstract

In this study we provide the first palaeoseismological data for the Galera Fault, an active strike-slip fault located in the Central Betic Cordillera. one of the most tectonically active areas of the Iberian Peninsula. We analysed palaeoseismological trenches in two sites located in the central sector of the fault, where we identified evidence of several surface rupture events deforming recent Holocene deposits. After constraining the age of these deposits, we constructed time-stratigraphic OxCal models that resulted in probability density functions (PDFs) of the ages of each palaeoevent. Analysing the degree of overlap of PDFs between the two sites, we proposed a surface-rupturing history for the Galera Fault, including seven events since ca. 24000 BC. Finally, through a Monte Carlo simulation, we calculated recurrence intervals of ca. 2748 ± 3419 yr between events. Our results, together with the palaeoseismological data of adjacent structures, will be the base for improve future seismic hazard assessments in the study area.