Different characteristics of strike-slip faults and the formation of large and medium-scaled oil and gas fields in the Liaodong Bay Depression

Strike-slip fault activities are common in the Liaodong Bay Depression.There are five major strike-slip fault zones, including the western strike-slip fault, Liaoxi extensional strike-slip fault, Liaozhong1 fault, Liaozhong2 fault and Liaodong1 fault.The characteristics of these faults are obviously different, generally strong in the east and weak in the west.As a result, the faults are divided into two fault zones: a "single and strong strike-slip fault zone" in the east and a "duplex and weak strike-slip fault zone" in the west.The eastern strike-slip activities are strong and the strike-slip features are obvious.The western strike-slip activities are weak and only a part of them shows strike-slip characteristics.The differences among strike-slip faults result in the formation of different strike-slip structures.These also control the formation of different types of traps as well as the migration and preservation of oil and gas, which ultimately determines the formation and distribution of large and medium-scaled oil and gas fields.