Geological Structure Analysis Of The Shaliuquan – Shengge Area In Qaidam Basin Northern Margin

The study area is located in the intersection of northeast of Qilian and Qaidam Basin.From north to south across southern Qilian, Zongwulong and northern margin of Qaidam three tectonic units.Because of its special tectonic location,each structural unit had experienced many times in different periods of tectonic action since long-term.Since superposition the tectonic development stage,its had formed a complex geological structure situation.Based on previous studies and field geological survey,treating structural features, division of tectonic units,the tectonic evolution process and other aspects as the starting point,we detailed study the geological structure of the area of the Shaliuquan and Shengge and obtain the following conclusion:1.Because of the particularity tectonic location in the study area,its area faults, folds, ductile shear zone, joints, cleavage, structural features are very developed. Throughout the study area geological formation and structure features,we can come to conclusion that the main direction of the tectonic line is NWW.2.Jinning tectonic cycle and Caledonian tectonic cycle are two important stages of the tectonic evolution of this area.Jinning movement had formed the Proterozoic metamorphic crystalline basement and cover.Then,this area enter into the evolution stage of intracontinental compression,formed a series of the ductile shear zone,fold structure, accompanied by a large number of emplacement of granite magmayism.The NWW fracture of this region were formed in the galedonian tectonic cycle.3.Tectonic unit in the area from north to south, can be divided into three Third tectonic units: the South Qilian tectonic belt, the Zongwulong tectonic belt, northern margin of Qaidam Basin.The northern margin of the Qaidam basin tectonic belt is divided into Oulongbuluke plot,Shaliuquan Secondary Tectonic unit,Maoniushan Secondary Tectonic unitSecondary Tectonic unit and ten fourth tectonic units.4.The tectonic evolution can be divided into four stages: the Paleoproterozoic basement formation and evolution stage, ancient plate cracking, subduction and collision orogenic stage, the Devonian- Triassic evolution stage, and continental basin evolution stage in the Cenozoic.