Threat to LNG exports as Japan unlocks gas AUSTRALIA'S multi-billion-dollar a year liquefied natural gas export industry faces a new threat after its top customer - Japan - used groundbreaking technology to potentially unlock vast new subsea gas deposits just off its coast. Japan announced this week that it had successfully extracted gas from a deposit of methane hydrates - or fire ice - buried 1km beneath the sea in what's believed to be a world first.