Abstract

Optimizing field development in the Malleswaram field of the Krishna-Godavari Basin requires a more precise understanding of the stratigraphic zonation and structural disposition of the Syn-rift Nandigama Formation. Previous classifications, such as the Sand 10+20 scheme, lacked the resolution to effectively model facies distribution, depositional environments, and reservoir continuity. This limitation was further compounded by complex sediment dispersal patterns, resulting in challenges for reliable reservoir characterization and development planning. An integrated approach combining electro-log correlation, core data, cutting sample descriptions, and seismic interpretation was adopted to enhance resolution of stratigraphic zonation. The Nandigama pay zones were subdivided into four arenaceous units (Unit-I to Unit-IV) above a distinctive red claystone marker that acts as a reliable stratigraphic marker across the field. Unit-wise analysis revealed shifts in sediment input—from axial fluvial systems to fan deltas—providing insights into reservoir distribution and quality. Electro-log correlation coupled with seismic interpretation supported identification of unit thickening/thinning trends and lateral continuity, from basement highs to deeper grabenal areas. This framework significantly improves understanding of the Nandigama formation in Malleswaram area and can support more effective field development planning.