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The discovery of large gas hydrate accumulations in arctic
permafrost and beneath the sea along the continental margins of
the world ocean is estimated at about 20,000 trillion m3. The
figure is astounding and scientists searching for a cleaner energy
source have jumped the bandwagon of exploration and exploitation
of this gigantic albeit sleeping resource. Recently several countries
including Japan, India, United States, Canada and China have launched
national projects. In India, a National gas hydrate program was
launched in 1997 by ministry of petroleum and natural gas with
participation of all national oil/gas exploration companies. Gas
hydrate occurs here in deep water. Based on processing of 2D and
3D seismic data and geological consideration, about 1400 sq. km.
area has been delineated as potential gas hydrate prone. Krishna-Godavari
and Andaman offshore areas have got clear indication of BSR. Therefore
initially Krishna-Godavari has been identified as a model field
laboratory for further efforts up to the stage of pilot production
testing of gas hydrates. Seismic, Side Scan Sonar, Sparker, AVO
studies have been carried out. Various geochemical proxy indicator
studies on shallow cores viz. TOC, absorbed gas, carbon isotope
analysis, pore water chemistry and microbiological studies of
indicator microbes like methanogens, methanotrophs, sulfate reducers
and denitrifiers are being carried out for prioritization of locations.
The coring through gas hydrate will lead to exact resource estimations.
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