The Tectonic Characteristics And Its Structural Reason In The .nan Baxian-hai Belt Of The North Margin Of The Qaidam Basin

Nan Baxian-Hai belt is in the central western part of the North Qaidam. Due to tectonic movement over, the impact of construction is well developed, it is difficult to explore oil and gas. But, since the 20th century, the study area has been found more oil and gas reservoirs and it have been the current hot key areas of exploration of the Qaidam Basin, therefore, the analyze of structural characteristics and its causes is not only beneficial for exploration of oil and gas but also important and significant for oil and gas exploration in the entire northern margin.Paper analysis of the regional tectonic evolution in a brief, and then , made a structure outline map, geological cross section, summed up the basic characteristics of fault structures, flat distribution rules and profile combination style in the study area.we think that the plane distribution of fold is the "right column type".faults are dip to the South, and also the ma xian fault which is the cents sinistral of the study area is a strike-slip characteristics. Structural styles of the study area can be divided into three major types, they are structural style compression, strike-slip and extensional tectonic style. Based on the residual thickness of the western part of North Qaidam,we analyze the old structure of the Mesozoic and Cenozoic Paleogene and Neogene.We think that the study area was a whole the ancient hill in the Mesozoic, and that the bulge has been extended to the early of Oligocene,Ma Xian fault is turn up in the end of Indo moment, it control the Mesozoic to Cenozoic Paleogene deposition of study area and its north area. According to stratigraphic contact and distribution structure orientation, cutting, analyzes the the main fault, fold formation age and tectonic stress orientation in study area. It is conclude that ,the Tsushima ancient uplift is caused by the combined effects of closure of Paleo-Tethys role of Indo-Chinese movement and differences arising.Ma left-lateral strike-slip fault cents to thrust based activities by the end of the Pliocene of the Indian plate pushing rapid and sustained, resulting in nearly a north-south compressive stress results.