Mumbai High Metamorphic Basement Reservoirs—An Integrated Workflow Based Approach for Fracture Modelling and Real Time Planning and Monitoring

Abstract

The Mumbai High field in the Western Offshore in India, is a priority area for extending the concept of fracture characterization in metamorphic basement reservoirs. The basement in the Mumbai High is hydrocarbon bearing in few areas proximal to major fault damage zones and intersections of major regional tectonic cross trends. The challenge remains in characterizing such basement reservoirs with significant heterogeneities in mineralo-facies, in situ stress fields, seismic amplitudes, fracture properties and connectivity, and flow potential. This necessitated the development of an integrated static fracture model workflow assimilating structural modeling, seismic and petro-physical interpretations for fracture drivers and geo-cellular fracture modeling, fine-tuned using geological concepts and point data extracted from well data analyses. The deterministic geo-cellular fracture model thus prepared has been calibrated with real time well observations and has been found to satisfactorily explain anomalous hydrocarbon accumulation and flow pattern in basement wells penetrated in excess of 100 m and tested in the area. The adopted workflow has helped planning for well-evaluating and exploiting basement reservoirs as well for the real time monitoring of wells.