Reservoir facies at different stratigraphic levels of the Cenozoic. Bioclastic mudstone and/or wackestone facies, pelletoidal mudstone and/or wackestone facies, and bioclastic grainstone facies in Bombay High, Bassein, and the shelf-edge areas, respectively. Depositional model. East-west lithofacies cross section, shelf-lagoon to shelf-margin depositional setting. Basin configuration, water energy, and periodic fluctuations in sea level are the dominant factors that controlled the development of reservoir facies.--Modified journal abstract.