Mianlue paleo-suture on the southern margin of the Central Orogenic System in Qinling-Dabie-with a discussion of the assembly of the main part of the continent of China
ZHANG Guowei, CHENG Shunyou, GUO Anlin,DONG Yunpeng, LAI Shaocong, YAO Anping(Key Laboratory of Continental Dynamics, Ministry of Education/Department of Geology,Northwest University, Xi'an 710069, Shaanxi, China)
The Mianxian-Lueyang (Mianlue) tectonic zone situated on the southern margin of the Central Orogenic System of the Qinling-Dabie origin is an important tectonic belt that divides China's continental tectonics into the northern and southern parts and links the eastern and western parts of the tectonics. Studies of the tectonics, sedimentary formations, geochemistry, paleontology and isotope dating and metamorphism-deformation in the area demonstrate that apart from the Shangdan suture zone the Mianlue tectonic belt represents another plate suture zone in the Qinling-Dabei orogen. It opened and spread as a juvenile ocean during the Middle-Late Devonian, commenced subduction during the Late Permian and underwent continent-continent collision in the Middle-Late Triassic. Its final suturing in the Indosinian marks completion of the assembly of the main part of the continent of China; therefore it has great scientific significance.