1. China University of Petroleum (East China), School of Geosciences, Qingdao, China; Pilot National Laboratory for Marine Science and Technology (Laoshan), Qingdao, China; and Shandong Provincial Key Laboratory of Deep Oil and Gas, Qingdao, China.
2. China University of Petroleum (East China), School of Geosciences, Qingdao, China; Pilot National Laboratory for Marine Science and Technology (Laoshan), Qingdao, China; and Shandong Provincial Key Laboratory of Deep Oil and Gas, Qingdao, China. (corresponding author)