Geophysical appraisal of the Abu Madi gas reservoir, Nile Delta Basin, Egypt: Implications for the tectonic effect on the lateral distribution of petrophysical parameters

The tectonic deformation has a significant influence on the hydrocarbon reservoirs properties. The effect of this process focuses on the lateral distribution of the petrophysical parameters characterizing the hydrocarbon reservoirs. The main objective of the current study is to perform a petrophysical examination of the Abu Madi gas reservoir which is the greatest gas-bearing reservoir at Nile Delta Basin in order to examine how far the Messinian tectonics affected the lateral variations of these petrophysical parameters. This petrophysical evaluation was performed based on the wireline log data acquired for five wells, namely, Abu Madi-2, Abu Madi-7, El Qara-3, Nidoco-7, and Nidoco-9 drilled within the Abu Madi Paleo-Valley. The petrophysical assessment for the most promising zone intervals within the Abu Madi sandstones in the inspected wells show that the total porosity varies between 17% and 22%, the effective porosity ranges from 7% to 19%, the shale volume fluctuates between 16% and 30%, hydrocarbon saturation varies from 37% to 76%, and the bulk volume of water varies between 0.02 and 0.09. These significant variations in the petrophysical properties of the Abu Madi reservoir are attributed to the tectonic influence during the deposition of the Abu Madi Formation as a part of the Late Miocene syn-rift megasequence in the Nile Delta Basin. This conclusion confirms that the petrophysical properties of sandstone reservoirs are function of tectonic and structural deformation.