"Stocks of a potential new source of natural gas in the sea-floor are much smaller than previous estimates have suggested, an expert claims.
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The findings are presented in the academic journal Earth Science Reviews.
Gas hydrates are deposits of ice-like crystals that trap natural gas under conditions of high pressure and low temperature such as those found in sea-floor sediments or in permafrost.
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But gas hydrate recovery carries a considerable risk. Destabilisation of hydrate reserves could cause sudden, massive releases of gas from the seafloor, threatening drilling platforms and ships. "Drilling gas hydrates is estimated to be six times more expensive than exploitation of oil and other gas sources," said Prof Bahman Tohidi, director of the Centre for Gas Hydrate Research in Edinburgh."
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http://news.bbc.co.uk/1/hi/sci/tech/3493349.stm