秦岭-大别中央造山系南缘勉略古缝合带的再认识——兼论中国大陆主体的拼合

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

秦岭-大别等中央造山系南缘的勉略(勉县-略阳)构造带是中国大陆构造中划分南北、连接东西的重要构造带。构造、沉积、地球化学、地球物理、古生物和同位素定年以及变质变形、岩浆活动等多学科综合研究证明,勉略构造带先期原是秦岭-大别造山带中除商丹缝合带以外的另一条于中—晚泥盆世扩张打开、晚二叠世开始俯冲、中—晚三叠世陆-陆碰撞造山的古板块缝合带,也是中国大陆印支期完成其主体拼合的主要结合带,具有重要的科学意义。

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.