Chinese scientists have discovered two sites of gas hydrates, or combustible ice, which are exposed on the sea floor in the South China Sea. China declared its first success in collecting samples of combustible ice in the South China Sea on May 18 this year.
The Chinese Academy of Sciences institute of oceanology said on Friday that the discoveries were made during a month-long expedition in the western Pacific Ocean undertaken by the research vessel Kexue.
The two sites are at about a depth of 1,100 meters. It is the first time exposed combustible ice has been discovered in sea areas under the jurisdiction of China, according to the institute.
Combustible ice usually exists in deep sea sediment or tundra areas which have high pressure and low temperature necessary for its stability. It is rare to see the substance exposed on sea floor.
Combustible ice can be ignited like solid ethanol. One cubic meter is equal to 164 cubic meters of regular natural gas.
China started research on the energy source in the late 1990s. Its first gas hydrate samples were collected in the South China Sea in 2007.
China's success in mining gas hydrate in the South China Sea is a breakthrough that could revolutionize the global energy industry, and prove more significant than the United States' shale gas, experts said.
Combustible ice is formed under low temperature and high pressure in permafrost under the sea. One cubic meter of the hydrate can release about 160 cubic meters of gas, which would emit only half the amount of carbon dioxide produced by oil or coal. No country has been able to produce it commercially due to tough conditions and pollution concerns.
Combustible ice is perhaps another 15 years away from commercial use, but its successful mining in China is a breakthrough nevertheless.
China is eager to replace conventional energy, including coal, quickly with clean energy sources, to optimize the energy structure and relieve problems caused by energy shortages.
