1. China University of Geosciences, Key Laboratory of Tectonics and Petroleum Resources, Ministry of Education, Wuhan, China and China University of Geosciences, School of Earth Resources, Wuhan, China.(corresponding author); .
2. The University of Texas at Austin, Bureau of Economic Geology, Jackson School of Geosciences, Austin, Texas, USA..
3. Tianjin Branch of China National Offshore Oil Corporation Ltd., Tianjin, China..