Mesozoic plate boundary in East China-Korean Peninsula: a revised model of plate indentation

The Dabie-Sulu Orogenic Belt owes its origin to the collision of the Sino-Korean plate and the South China or the Yangtze plate in East China during Late Permian and Triassic. The eastward extension of this orogenic belt has been a hot debate in past decades. This article summarizes the latest research results on this plate boundary. More data newly acquired tends to support that the Gyeonggi Massif and its southern part are still belonging to the Sino-Korean Plate. Therefore, the Sulu Orogenic Belt does not extend to the entire peninsula. Taking into account of the Mesozoic tectonic characteristics of the Tanlu Fault System and the orocline structures of the Lower Yangtze area, this article supports the model of collision-related indentation. According to the newly defined plate boundaries in this model, most of the Korean Peninsula belongs to the Sino-Korean Plate, just the southwest Gyeonggi Massif remains part of the Yangtze Plate. The southern section of the Tanlu Fault and the Jooggaryeong Fault in Korean Peninsula are the plate transform boundary of the Yangtze Plate indented into the Sino-Korean Plate. These two faults exist as collision transform faults in Indosinian epoch, and as strike-slip faults with splays northward in Yanshanian epoch.