Characterization of fault structures in southern Sinai Peninsula and Gulf of Suez region using geophysical data

Abstract

In this work, an integrated study was carried out to delineate the prevailing subsurface fault structures and their tectonic position in the southern part of the Sinai Peninsula. The study area is selected due to its active tectonic situation. This study is implemented using the available geophysical data; these include magnetic, Bouguer gravity, seismic data to trace the delineated fault structures in shallow subsurface and magnetotelluric data to trace down these structures at deeper depths. To achieve this goal, several techniques have been applied in the interpretation of the data including least squares, trend analysis, Euler deconvolution, 3-D modeling and analytical signal techniques. The results indicate that the main fault structural trends are N 35°–45° W, N 15°–25° E and E–W directions, in accordance with the regional tectonics of the Gulf of Suez rift and Gulf of Aqaba, transform as well as the Tethyan tectonics. The depths to the basement rocks are widely varying from 0 km to about 4 kms. Two seismic lines (EG 31 and MP-70), compiled by Egyptian General Petroleum Cooperation, have been interpreted as well as a geologic cross section derived from well-logging data. The results illustrate that the study area has been affected by the fault structures prevailing there and affecting the rock units and dividing them into several major blocks. The results obtained from 2-D inversions of magnetotelluric soundings show that the fault structures that have E–W trends extend to deeper depths than faults which have N35°–45°W, N15°–25°E.