Gas hydrate reservoir identification, delineation, and characterization in the Krishna-Godavari basin using subsurface geologic and geophysical data from the national gas hydrate program 02 expedition, offshore India

Abstract

Abstract During the National Gas Hydrate Program Expedition-02 (NGHP-02), logging while drilling, conventional coring and pressure coring, wire-line logging, vertical seismic profiling and formation pressure measurements were carried out in deep water portions of the Krishna-Godavari (K-G) and Mahanadi Basins along the eastern continental margin of India. A total of 42 research holes were completed for comprehensive data collection and measurements related to gas hydrate reservoir and host sediments properties with an objective to identify producible gas hydrate in sand-rich reservoirs that would be suitable for a future pilot production test. Shipboard and post cruise evaluation of physical properties measurements, pressure core dissociation studies and gas analysis of recovered core samples have confirmed the occurrence of sand hosted gas hydrate deposits in three operational areas named during NGHP-02 as Area B, Area C and Area E in the deep-water portion of the K-G Basin. The energy resource potential of the discovered gas hydrate deposits in the K-G Basin depends on many factors, including the quantity of available gas trapped as gas hydrate in the basin. Therefore, this study was undertaken to identify, characterize and delineate the discovered and confirmed gas hydrate prospects in the K-G Basin. Based on the integrated analysis of regional seismic data and NGHP-02 acquired borehole data, a total of 8 sand-rich reservoir constrained gas hydrate prospects have been identified and mapped in the K-G Basin (Areas B, C, and E) as described in this report.