Integrated Geophysical Investigations to Identify Promising Locations for Gold Bearing Sulfides Mineralization at Wadi El Abiad, Shalatien Province, Southeastern Desert, Egypt

Abstract

<title>Abstract</title> The study area represents part of Wadi El Abiad in Shalatien province at the extreme southeastern corner of Egypt. It lies at latitude 22^○ 51´ 00˝ and longitudes 35^○ 14´ 00˝ to occupy an area of about 0.26 km². The area is essentially covered by Precambrian basement rocks, mainly granodiorite, and characterized by low to moderate topography. The aim of this study is to locate possible structural features and their deposits of mineralization, which hosted primarily in the shear or alteration zones within volcanic rocks. Therefore, integrated geophysical methods were employed through the use of ground magnetic, self-potential, gradient resistivity and induced polarization reconnaissance mapping and detailed 2D resistivity and induced polarization profiling to delineate the mineral ore deposits in terms of depths and extensions. The inspection of RTP map shows the presence of two major faults affecting middle of the study area trending E-W and major NW-SE uplifted trend appears clearly in the first vertical derivative map (FVD). The calculated average depth from the power spectrum curve equal 60 m for the regional component and 30 m for the residual one. At source parameter image (SPI) and analytical signal (AS) maps, the NE-SW, NW-SE, NEE-SWW and NWW-SEE trends show more shallow depth as the presence of basement rocks. The basement relief map illustrates that, the maximum values of the depth to the basement rocks are located nearly at the central part of the map, at extreme east and west edges in the center of the map, and also at the south edge of the map. The apparent chargeability map shows positive anomalies, about 750 msec, to the south. Three of them are located quite coincident along the interpreted faults derived from the magnetic data and correspond to low SP anomalies, about − 20 mv, and relatively low resistivity anomalies, about 75 Ω.m. Such anomalies indicate possible expected mineralization locations in the subsurface. The results of 2D-resistivity and IP inversions indicated that there are different anomalous zones of high conductivity and chargeability at depths ranging from 10 to 20m to indicate probable locations of ore deposits and/or disseminated minerals. At least three of these anomalies were recommended for core drilling and geochemical analysis to evaluate the mineral potentiality of the study area.