THE GAS HYDRATE IN THE SOUTH CHINA SEA

The area where water depths are more than 400m is 93 ×104 km2, there may ex-ist gas hydrates. The topography on the slopes and rises is complex,there are a lot ofsea mounts, sea hills,troughs, sea valleys, submerged reefs and shoals. There were a se-ries of tectonic movements in Mesozoic and Cenozoic in the area, but there was no move-ment since end of middle Miocene. There was regional subsidence, and a sub--horizontalsediments were deposited in a stable environment since end of middle Miocene. Underthese sub--horizontal sediments there were many faults formed by the movements. This isfavourable for the up--going fluid from below sediments. The sediments since end of mid-dle Miocene have been in the stable zone of gas hydrate,the gases in the fluid from belowsediments flowed up along the faults into the sediments since middle Miocene as a gassource forming the gas hydrate,including the gases formed in the sediments since middleMiocene. Therefore, we believe that there is abundant gas hydrate in the slopes and risesof the South China Sea. We calculated the gas hydrate resources in the area according tothe data obtained from the South China Sea area and world's parameters on the gas hy-drate. The total resources are 6. 435 ×1013 --7. 722 ×l0l3 m3 gases.