| Abstrakt: |
This work attempts to solve the knowledge gap in the Sharyoof oil field within Block 53, Say’un-Masilah basin, eastern Yemen using acquired wells logs data. In this area, the Qishn Sandstone is considered to be the major member of the Qishn Formation, which exhibits good reservoir features. To determine the traps of hydrocarbons, this Member was divided into S1A, S1B, S1C, and S2 sub-units bounded by shale and carbonate layers. Thus, the principal objective of this study is the establishment of the lithological components for the Sa’ar and Qishn Formations in addition to the determination of hydrocarbon entrapment style in Qishn sandstone Members from the Sharyoof oil field. In this study, the used data were collected from six wells covering gamma-ray, caliper, deep and shallow later loge resistivity, photoelectric absorption index, and porosity tools (density, neutron, and sonic). The obtained results reveal that lithology is mainly composed of dolomite for Sa’ar Formation; sandstone interbedded with limestone, dolomite, and shale belonging for Qishn clastic Member, and limestone for Qishn Carbonates Member. Petrophysical parameters were integrated within the reservoir to identify the best potential hydrocarbon traps. The statistical analysis of petrophysical parameters showed that S1A and S1C are the best sub-units illustrating high porosity and hydrocarbon saturation, which ranges between 15–22%, and 60–87%, respectively. These sub-units highlighted low clay volume, which is less than 23%. The S2 sub-unit demonstrates an effective porosity of up to 22%, a water saturation comprised between 12% and 100%, and shale volume that ranges between 0% and 25%. Horizontal isoparametric maps have demonstrated that hydrocarbon saturation increases with increasing porosity and decreasing clay volume toward the north and south–west for unit S1A, northwards only for S1C, and north-southwestwards for S2. Consequently, these findings support the proposition of new drilling wells in these directions. Alternatively, besides proposing a new drilling position, the originality of the present work lies in the identification of the lithological characteristics of the Qishn Formations. As such, this research can be used as a baseline study. |
Full text from SpringerLink