Abstract

Sedimentological and biostratigraphic analysis of more than 700m of well cutting samples and side wall core sample of three key wells (A, B and C) are carried out to understand the coral reef reservoir in terms of microfacies, porosity trends, diagenesis and depositional setup of coral reef unit of Early Miocene age (Bombay Formation) in the northern part of Heera- Panna-Bassein Area, Mumbai Offshore Basin (Figure1). The microfacies analysis of the carbonates of the studied interval are represented mainly by high energy packstone and boundstone unit along with low energy wackestone in study area. The presence of coralline boundstone in wells A, B and C shows the development of coralline patch reef. Coralline patch reef is slightly dolomitized in pay-I and is best developed in well C that is towards western part of study area as compared to wells A and B. The porosity in general is moderate to fair with presence of occasional vugs, intercrystalline, intracrystalline and framework pores. Potential reservoir facies are better developed towards the Eastern side of the studied area.