Evaluation of Reservoir Properties Using Wireline Logs of Well Sarai-Sidhu-1, Punjab Platform, Central Indus Basin, Pakistan

Abstract

The well Sarai Sidhu-01 is located on Punjab Platform, Central Indus Basin, Pakistan. Punjab Platform is the eastern part of Central Indus Basin, and tectonically it is the stable portion of Indus Basin, which was least affected during Tertiary Himalayan orogeny. This study attempts to decipher reservoir potential for hydrocarbon exploration. It aims to delineate a subsurface hydrocarbon bearing zone and to estimate the reservoir properties. A complete suite of wireline logs containing Caliper log (CALI), gamma ray log (GR), spontaneous potential log (SP), neutron log (ON), density log (OD), and resistivity logs (MSFL, LLS, and LLD) with all drilling parameters and well tops were utilized. The methodology adopted to accomplish this task includes the calculation of volume of shale (Vsh) by using gamma ray log and effective porosity (OE) by using density and neutron logs. Resistivity of water (Rw) was calculated by SPmethod, and the saturation of water (Sw) and the saturation of hydrocarbons (Sh) is calculated with the help of Archie’s equation. According to log signatures, Lumshiwal formation of early Cretaceous age encountered in well in the depth range of 5433 ft. to 5797 ft. was marked as a possible reservoir, and this zone was evaluated for its reservoir potential in detail using a set of equations. The average values calculated for different parameters are as follows: Vsh= 30%, OE= 17%, Sw= 46%, and Sh= 54%. The analysis shows that Sh is low, so it is inferred that Lumshiwal formation has a low potential and is economically not feasible for hydrocarbons production.