3-D stripping inversion based on measured terrestrial potential field and seismic data over Hodein Basin area, Southeastern Desert, Egypt

Abstract

SUMMARY This study aims to present a 3-D stripping inversion over the Hodein Basin area in the Southeastern Desert based on the Fourier approach and evaluate the method based on the availability of data constraints. Before submitting the data sets for inversion, the gravity and magnetic data were subjected to process corrections, which enhanced the geological signal, thereby improving the inversion outputs. The Kharit-1 well was drilled in the central part of the basin area by Repsol in 1998. The interpreted seismic profiles revealed cumulative stratigraphic sequences in the study area, including basement complex, Kom Ombo Equivalent and Six Hills formation. Based on these constraints, the 3-D model was constructed and produced good fit statistics with an error of approximately 1.4 per cent for the gravity data and 9.7 per cent for the magnetic data. The basement layer becomes deeper in the middle of the basin, reaching a value of −2687 m around Wadi Kharit and Wadi Timsah. The basement layer is exposed and shallow in the NE and SW flanks of the main basin. The top of Kom Ombo Equivalent formation matches well with the basement relief. It reaches at the middle of basin area −1968.5 m, the greatest thickness at Wadi Timsah, up to −1200 m, while it decreases to the northwest, where it reaches −185 m. The top of the Six Hills formation reveals a shallow depth of 430 m asl along the basin area, except for the middle part, which reaches −1200 m. Based on four seismic depth profiles, an uncertainty investigation of the inversion results was performed, showing an error of approximately 10 per cent. In conclusion, the resultant basement and two stripping sedimentary layers reveal that the study area is characterized by a broad basin directed in the NW direction and dissected by normal faults, forming small subbasins.