Abstract

3D distribution of syn- and post-depositional facies is a prime requirement in geoscientific models. The task become more challenging in heterogenous reservoirs due to their complex lithological variations. To address this situation, distributions of facies is a prerequisite for the discrete facies log created from well log data at respective well locations in a 3D model. The facies log is upscaled as per the layering scheme and representative facies for the geo-cells is defined. Additionally, mapping and connectivity in 3D models are crucial exercises in facies modelling process. A stochastic facies modelling technique was employed to develop a lithofacies model for the mid-Eocene age Hazad Member of Ankleshwar Formation in Jambusar-Broach Block (JBB) of Cambay Basin. Using Sequential Indicator Simulation (SIS), multiple realizations were generated for the representative facies-sand, silt, shale and coal. Variogram analysis proved to be a crucial step in this process, as it established spatial correlation and realistic distribution of lithofacies within the model. This distribution was validated against known well locations, confirming its reliability.