National Key Laboratory of Deep Oil and Gas University of Petroleum(East China) 266580;
Laboratory for Marine Mineral Resources Evaluation and Exploration Technology National Laboratory for Marine Science and Technology 266071;
PetroChina Dagang Oilfield Company 300280;
Sinopec Shengli Oilfield Company 257001;
Bohai Bay Basin; PERMIAN; clastic rock; diagenetic evolution; reservoir-forming mechanism; secondary pore;