Impact of diagenetic processes on the petrophysical properties and quality of the Miocene “Reefal limestone” reservoir in Al-Hamd field, Gulf of Suez, Egypt

Abstract

Unconventional reservoirs have burst with a great force in the oil and gas worldwide production. Reefal limestone reservoir is one of them. The present study deals with the reefal carbonate Hammam Faraun Member in Al-Hamd oil field. This study focus on the interpretation of sedimentological and petrophysical data to show the effect of diagenetic processes on middle and lower Miocene reefal carbonate reservoirs in Al-Hamd oil field. Comprehensive petrophysical analysis for Hammam Faraun Member was performed using wireline logs and core data to determine the proper petrophysical parameters. Of the reservoir intervals. The analytical reservoir rock achieving the main reservoir parameters as shale content (Vsh), effective porosity (Oeff), water and hydrocarbon saturation (SW and Shr) as well as the net-pay thickness. The Formation Micro Imager (FMI) was also applied to detect the variation, types, and directions of the fracture systems that present in the lower and middle Miocene reefal limestone reservoir. Petrographic analysis was done, indicating the presence of a clear effect of diagenetic factors on the quality, productivity, and efficiency of the reefal limestone reservoirs behavior. The diagenetic factors include dolomitization, slicification, recrystallization, and solution process which affect greatly the petrophysical characteristics of the reefal carbonate Hammam Faraun reservoir in the study area. The core analyses were also used to detect the paleo environment, associated textural/ lithological and sedimentological characteristics to gain and understand the factors responsible for the productivity behavior of the reservoir in the Al-Hamd oil field. Rock facies have been divided as specific characteristics and were further described considering their color, texture, grain-size characteristics, and the depositional and biogenic sedimentary structures.