[an error occurred while processing this directive] BBC News
watch One-Minute World News Last Updated: Tuesday, 17 February,
2004, 12:53 GMT Ocean methane stocks 'overstated' By Paul Rincon
BBC News Online science staff  Hydrate, USGS Commercial
exploitation of hydrates may still be possible Stocks of a
potential new source of natural gas in the sea-floor are much
smaller than previous estimates have suggested, an expert
claims.  Gas hydrates contain huge quantities of natural gases -
mainly methane - and are tipped as a future energy source.
Estimates of hydrate-bound gas fell steadily in the last 30
years due to growing knowledge of their distribution and
concentration in sediments.  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.  Limited
reservoir  One widely cited estimate proposes that 10,000 gi