天然气水合物——石油天然气的未来替代能源

Gas hydrate,a future energy resource.

天然气水合物是甲烷等天然气在高压、低温条件下形成的冰状固体物质。据估算,全球天然气水合物中碳的含量等于石油、煤等化石能源中碳含量的两倍,这是一个非常诱人的数字。在人类面临化石能源即将枯竭的时候,科学家和各国政府都把眼光投向这一未来能替代化石能源的新能源。南海在新生代构造演化历史、沉积条件、沉积环境等方面都显示这里具有生成和蕴藏巨大天然气水合物资源的条件,因此,这里可能成为中国在不远的将来之新能源基地。

The gas hydrate, being a solid material, is formed from the methane and water under the high-pressure and low-temperature. Laboratory experiments showed that one cubic meter of gas hydrate could liberate 164 m^3 gases. The total resources of the gas hydrates in the world,as calculated by different methods amount to (5×10^(15 ))～ 8×10^(18) m^3, which is equal to twice of the total resources of the oil and gas, coal, and other fossil fuel in the world. At present, humankind is facing the exhaustion of fossil fuels, therefore, the scientists and world governments should focus on gas hydrate resources. Research in the South China Sea showed that gas hydrates are formed under different conditions. In the northeastern part of the South China Sea, high salinity water has flowed from Philippine Sea, resulting in high organic productivity and accumulation of organic-rich sediments.During these periods of high productivity,the rate of sedimentation was very high,thereby providing excellent conditions for the formation of gas hydrates.In addition, since the end of the Miocene, the Philippine Sea plate has collided with Asian plate in Taiwan Region,resulting in the tectonic extrusion of the northeastern part of the South China Sea along a northwest direction. Because of this tectonic extrusion, fluids in the sediments were especially active, further stimulating the formation of the gas hydrate. On the basis of these analyses, we suggest that throughout the continental slope of the South China Sea conditions existed are favorable for the formation of gas hydrate. Therefore we believe that the northeastern part of the South China Sea should be rich in gas hydrate.