Paleoseismology of active faults based on multiscale seismic imaging

Abstract

The study of active structures offshore requires very-high resolution seismic imaging in order to observe the most recent layers below sea floor. In the other hand, high penetration methods are necessary to observe deeper reflections for understanding the evolution of the structure throughout the time. The aim of our study is to establish the seismic potential of the offshore segment of the Carboneras Fault, Eastern Betics, based on multiscale seismic imaging. Three different scale methods have been acquired and are compared here: very-high-resolution sub-bottom profiler TOPAS, very-high-resolution single-channel seismic (Sparker) and high-resolution multi-channel seismic. From seismic profiles, faulted Quaternary layers suggest that the Carboneras Fault is active. Sediment coring and dating analysis are used to consider ages for key reflectors observed in TOPAS profiles, and a change in the vertical slip-rate through the Quaternary is inferred.