Sequence Stratigraphic Evaluation of Lower Goru Sequence (Massive Sands) and Sembar in Block ‘X’, Lower Indus Basin, Pakistan

Abstract

Block ‘X’ is situated in the prolific oil- and gas-producing Lower Indus Basin of Sindh Province, Pakistan where the Sembar-Goru Petroleum System features high-quality prodeltaic to open marine source rocks in the Lower Cretaceous Sembar Formation, and sandstone reservoirs in the Sembar and Lower Goru formations. Pakistan Petroleum Limited (PPL) is currently producing gas and condensate from several the wells in the study area and is actively drilling new targets. Most of the wells have been targeted for structural traps (Horst and Grabens) due to improved structural mapping based on good 3D seismic coverage. The thesis project aims at reconstructing a sequence stratigraphic framework of the Sembar and Lower Goru megasequences by integrating all the available data which can help in an improved understanding of the play fairway. The goal is to propose a model that can help in finding new oil and gas prospective zones which might have been overlooked by the existing sequence stratigraphic model being used by the operating company’s (PPL) exploration team. The current stratigraphic model by PPL is predicting sands in Massive Sand Formation based on a shallow marine highstand/transgressive system while the thesis project has predicted localized development of lowstand progrades in the Massive Sand Shallow Sequence which on detailed sequence stratigraphic analysis can open a new exploration play for the Block.