The division of tectonic units of Beishan area, Gansu-Inner Mongolia

This paper gives some general principles about the division and naming of tectonic units of Beishan area. According to the theory of plate tectonics and polycyclic opening-closing tectonics,Beishan area is divided in to three first-order tectonic units,eight second-order tectonic units and twenty-six third-order tectonic units. There are two suture zones in Beis-han area:the Hongliuhe-Niujuanzi-Xichangjing suture zone(Early Paleozoicera)and the Hongshishan-Pengboshan suture zone(Upper Paleozoic era),and the latter is the final plate junction between the Tarim Plate and Kazakh stan Plate.