1. Chinese Academy of Sciences, Institute of Geology and Geophysics, Key Laboratory of Petroleum Resources Research, Beijing, China and University of the Chinese Academy of Sciences, College of Earth and Planetary Sciences, Beijing, China.
2. Chinese Academy of Geological Sciences, Institute of Geology, Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources, Beijing, China.
3. Chinese Academy of Sciences, Institute of Geology and Geophysics, Key Laboratory of Petroleum Resources Research, Beijing, China and University of the Chinese Academy of Sciences, College of Earth and Planetary Sciences, Beijing, China. (corresponding author).