A review of the geochemistry of methane in natural gas hydrate
The largest accumulations on Earth of natural gas are in the form of gas hydrate, found mainly offshore in outer continental margin sediment and, to a lesser extent, in polar regions commonly associated with permafrost. Measurements of hydrocarbon gas compositions and of carbon-isotopic compositions of methane from natural gas hydrate samples, collected in subaquatic settings from around the world, suggest that methane guest molecules in the water clathrate structures are mainly derived by the microbial reduction of CO2 from sedimentary organic matter. In only 2 regions, the Gulf of Mexico and the Caspian Sea, has mainly thermogenic methane been found in gas hydrate. At a few locations, where the gas hydrate contains a mixture of microbial and thermal methane, microbial methane is always dominant. Continental gas hydrate, identified in Alaska and Russia, also has hydrocarbon gases composed of >99% methane, with carbon-isotopic compositions ranging from -41 to -49???. -from Author
Citation Information
Publication Year | 1995 |
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Title | A review of the geochemistry of methane in natural gas hydrate |
Authors | K. A. Kvenvolden |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Organic Geochemistry |
Index ID | 70018724 |
Record Source | USGS Publications Warehouse |