IGX

Set a lighter to an icy block of methane hydrate, a naturally frozen combo of methane gas and water, and flames spew forth at random.

However unlikely this fluke of nature may appear — burning ice — it could hold the keys to a vast wealth of untapped, clean-burning methane gas thought to exist deep beneath the outer margins of most continental shelves.

Its contribution may be peripheral to the immediate needs of Western Europe and North America, currently drowning in cheap natural gas, but it present a potential lifeline to resource-poor nations like Japan, which already imports more than 90 percent of its fossil fuels.