Subsurface structures using a new integrated geophysical analysis, South Aswan, Egypt

Abstract

The Aswan High Dam located at the north of Nasser Lake in Aswan, Egypt, has a vital role because it is a multipurpose project for sustainable irrigation development, hydropower, and navigation improvement. In this work, we aim to detect the hazardous subsurface structures that control the South Aswan area and their causative source depths, through the application of both normalized standard deviation filters and deconvolution procedures. These computational approaches utilize a three-dimensional Euler homogeneity equation with unprescribed structural indices that is based on the properties of the differential similarity transformation on the available Bouguer gravity data. Hence, without any bias to a definite structural element (structural index), an automatic identification of the effective structural indices in the area is given. Moreover, possible vertical magnetic contacts are estimated from the reduced to pole magnetic anomaly map through an application of the tilt-depth technique. The mean focal depth of the earthquakes changes over time and migrates to shallower depths. The number of shallow events is increasing dramatically, whereas the corresponding magnitudes are decreasing. The integration of potential field data analysis with the new seismological and water level catalog (for the duration of 30 years) shows that the area began a hazardous cycle of activity (MI > 4) that could continue over the next few years.