SINGAPORE — Ice that burns? It sounds like a magician's trick. So do some of the exotic names given to gas hydrate — "flammable sorbet," "crystal gas" and "burning ice." But recent scientific surveys and test drilling in Asia and elsewhere have proven that this substance exists in massive, potentially recoverable quantities and that it could be an important commercial energy source for the future.

Indeed, some of the world's biggest economies and energy users, including the United States, Japan, China, India, South Korea and Canada, are racing to develop production techniques and equipment to tap gas hydrate and bring it to market within the next decade. For all of them, except energy self-sufficient Canada, the ability to tap new domestic sources of natural gas offers the prospect of substantially reducing dependence on expensive gas imports.

Hydrate deposits up to several hundred meters thick are generally found in two places: on or beneath the deep ocean floor, or underground close to the Arctic permafrost layer, where high pressure and cold temperatures turn natural gas (methane, ethane and propane) into semi-solid form.