Abstract:

Tectonic environment is an important factor of gas hydrate formation. Special structure bodies, such as accretionary prism, fault-folded system, mud dirpir and slide body are important geological reservoirs of gas hydrates. Based on studying of these special structure bodies and fluid movements for gas hydrate formation, six types of tectonic-controlled gas hydrate reservoirs including accretionary prism, buried anticline, basin-edge slope, fault-folded, slide and dirpir are summarized. The South China Sea is located at the junction of the Eurasian, the Pacific and the Indian-Australian plates, and it is one of the complex continental margins which are of active margin in early and passive margin in late. Five tectonic types of gas hydrate deposits including accretionary prism, fault-folded, dirpir, slide type and basin-edge slope are identified in the South China Sea.

Key words: gas hydrate, fluid movement, continental margin, tectonic control, ore-forming mechanism, the South China Sea