Magnetotelluric Characterization of the Alhama de Murcia Fault (Eastern Betics) - Preliminary Results

Abstract

The Lorca Earthquake (11/5/2011, Mw 5.2) stands as the most destructive in Spain over the last 50 years. It was interpreted as having occurred in an intersegment zone of the strike-slip Alhama de Murcia Fault (AMF). Within the research project “Intergeosima”, a multi parametric characterization and monitoring of the fault structure is ongoing, with the aim of developing a future Near Fault Observatory (NFO) to improve the understanding of the seismic behaviour of the fault in the short and medium term. In this work we present the preliminary results of a magnetotelluric (MT) survey carried out along the rambla de la Torrecilla (SW of Lorca). A more resistivity area might correspond to the Quaternary units, whereas the conductive areas might delineate the extent of the fault gauge materials. Further analysis and inversion of the data are necessary to obtain a more detailed picture of the extension and geometry below the fault zone.