Abstract

Identifying untapped hydrocarbon potential in mature plays requires a systematic and integrated reservoir characterization approach. This study presents a case study of the Pasarlapudi Play in the Krishna-Godavari Basin, India — a region with established hydrocarbon production and considerable scope for further exploration. The Eocene Pasarlapudi Formation, is a key gasproducing unit in East Godavari Sub-Basin. It comprises prograding deltaic sandstones deposited in nearshore to shelfal environment within a growth fault-controlled structural regime. The lower part of the Pasarlapudi Formation is characterized by thick, laterally extensive sands, while the upper part contains thinner, more discontinuous sand bodies, resulting in increased heterogeneity and complexity in reservoir distribution. A structured reservoir characterization workflow was implemented, integrating seismic and well data to reduce uncertainty and enhance subsurface interpretation. The process commenced with spectral enhancement of seismic data using Differential Resolution (DR) algorithm to improve the resolution of subtle stratigraphic features. Detailed seismic interpretation was carried out to delineate structural and stratigraphic frameworks. Multi well cross-plot analysis of P-impedance and Vp/Vs enabled clear separation between reservoir and non-reservoir facies. Rock Physics Modelling (RPM) established relationships between petrophysical parameters and their corresponding elastic responses. Pre-stack inversion was performed to derive key elastic attribute volumes. Facies and Fluid Probability (FFP) analysis was applied on the inversion outputs to predict the spatial distribution of hydrocarbon-bearing sands. This integrated reservoir characterization approach enhanced the understanding of reservoir architecture and proved effective in delineating untapped hydrocarbon zones within the Pasarlapudi Play supporting future exploration and development efforts.