Seismic Interpretation of the Subsurface Structures for Delineating the Occurrence of some Reservoirs in the Main Abu El-Gharadig Oil Field, north Western Desert, Egypt

Abstract

HE OBJECTIVE of this study is to delineate and evaluate the subsurface structural features and to determine the hydrocarbon potentialities of the Abu El-Gharadig basin, Western Desert, Egypt, particularly in the Main Abu El-Gharadig oil field. The zones of interest of this study are Abu Roash “E” and Upper Bahariya reservoirs of the late Cretaceous age. 20 2D seismic reflection profiles were used to evaluate the study area’s structural framework and to construct structural contour maps. So, two horizons were interpreted and picked, by using seismic well tie, to link between the seismic data (in time domain) with the well log data (in depth domain) and to generate synthetic seismogram to create a wavelet which is then compared with the seismic traces and well location, and to determine the stratigraphic boundaries of interest. After that, structural contour maps are constructed, which reveal that, all the area are influenced by normal faults trending E-W and NW-SE directions. The Fault polygons of the two horizons generally indicate three-way dip closure tilted fault blocks and also two-way dip closures forming horst and graben blocks. Beside the two zones of interest, we found the Paleocene-Early Middle Eocene Appolonia “B” and “C” horizons in the north eastern part of the study area of high amplitude and has a bright spot, which is not continuous in any other location of the study area. Therefore, we applied some techniques of the seismic attributes, to indicate the presence of wedging or channeling of limestone rocks, which may indicate commercially hydrocarbon potential.