Abstract

Gas hydrates exploration in India has been an intense area of research during the past two decades but slowed down during last 5 years. The present paper attempts to review the status of gas hydrate exploration in India which includes a summary of exploration and research efforts by several agencies and academic groups in India. The National Gas Hydrate Program (NGHP), initiated in 1997, has conducted two successful expeditions, NGHP-01 and NGHP-02, in 2006 and 2015, focused on identifying and characterizing gas hydrate deposits. These expeditions have yielded valuable data on the geological setting, distribution, and potential of gas hydrates in Indian deepwater basins. A review of gas hydrate exploration in India reveals significant potential, particularly in the KrishnaGodavari (KG) and Andaman Deep water Basin. Gas hydrate deposits are mainly in the channellevee complexes and are of biogenic origin. The hydrates are generated and deposited in-situ conditions and no deep thermogenic gas sources are reported. Moreover, the western offshore basins seem to be devoid of gas hydrate deposits since no seismic proxies (BSR, Blanking, pock marks, etc) are identified and reported so far. Mahanadi basin has also shown poor prospects, although seismic proxies are identified but drilled without any successful hydrate recovery (NGHP1). Gas hydrate reserves have been estimated by IEA’s India Energy Outlook 2021 as 1894 trillion cubic meters which seems exorbitant keeping in mind the hydrate layer thickness encountered so far are of the order of 30m (with exception of 90m thick highly saturated hydrate in fractured siltyclay in KG Basin-NGHP-1) and pool sizes are 10- 20 skm. Therefore, total reserve is envisaged much less and non-economic based on the analysis of available data and uncertainty involved. Overall, the gas hydrate exploration in India looks not so encouraging after analyzing available data.