Pre- and post-seismic displacements associated with the Aswan 2011 earthquake (M = 4.2) derived from recent geodetic GPS data

Abstract

Due to the importance of Aswan area, Egypt, it has been selected for the present study. Since 1982, after the main shock of November 14, 1981 with M = 5.6, several study programmes were initiated for monitoring seismicity and crustal movements at Aswan area (Tealeb 1996). Starting from 1997, GPS geodetic networks were established and observed many times in different campaigns. The observations are repeated twice a year. At the beginning of 2012, a moderate earthquake has occurred in the Aswan region with magnitude of 4.2 located at the southwest of the High Dam along Kalabsha fault. Before and after this event, these local geodetic networks were measured using GPS. Regional, Kalabsha-Sayal and Kalabsha networks were used in the present work. GPS data were processed using Bernese 5.0. The collected data before and after this event have shown that the area southwest of the High Dam and Kalabsha area suffered from stress and strain. The behaviour of the areas has changed after earthquake for pre-earthquake.