Establishme!lt of a GIS based on the interpretation of refu t sensing and geophysical data for the understantfing of the origin of the Qattara Depre.$sion, western desf!rt Egppt

Abstract

This study is mainly devoted to integrate the remote sensing and geophysical methods in the form of gravity and seismic reflection data through GIS for relating the surface and subsurface structural fault components of the Qattara Depression area, northern Western Desert, Egypt.

Gravity processing and interpretation have been carried out over the Qattara Depression area in the form of spectral analysis for regional and residual separation. Euler deconvolution and horizontal gradient were applied to estimate the depths of the deep-seated structures. Based on the processed gravity data, qualitative interpretation was carried out on the Bouguer anomaly contour map, the regional and residual anomaly contour maps. Quantitative interpretation was carried out to produce the output basement depth map. Deep and shallow-seated structures have been identified, as well as the depths to the deep-seated gravity causatives. The deep-seated anomalies in the concerned area have been dissected by a number of E-W stntctural features in the form of faults, which coincide with the Qattara Depression northern and western escarps. Shallow-seated anomalies show many complex faults, which are located just beneath the depression with N-S, E-W, and arbitrary intersecting faulting systems. From the delineated regional and local fault systems, the tectonic inferences have been identified to be of tensional types which caused by the E-W Mediterranean and NE-SW Syrian arc systems.