1. Institute of Geology and Geophysics; Chinese Academy of Sciences; Beijing 100029 China
2. Key Laboratory of Marginal Sea Geology; Chinese Academy of Sciences, South China Sea Institute of Oceanology, Chinese Academy of Sciences; Guangzhou 510301 China
3. R & D Center of BGP; CNPC; Hebei Zhuozhou 072700 China
4. CNPC Sichuan Petroleum Geophysical Prospecting Company 610200; China