| Northeastern margin of Qingzang Plateau is Qaidam - Qilian block, is the extension of the Qingzang Plateau to the leading edge of the mainland partand also the newest and important part of the formation. From Late Cenozoic to the current, the tectonic deformation of this block is very intense.The activities of the Late Quaternary thrust fault, strike-slip fault and active folding indicats that the whole region is suffering from crustal shortening and sinistral shearing. Altyn Tagh fault for the northwest edge of Qingzang block is a large north east left spin strike-slip faults which is composed of multiple second-order faults, is approximately 1600km long, and has thrust -left-lateral strike-slip characteristics .Generally, Altyn Tagh fault is divided into western,middle and eastern three sections.The eastern section is in the east of Akesai, the fractured left-slip rate descends along the east, and is relevant to the active reverse upfaulted thrust lifting of triple junction with Subei,Shibaocheng and Shule River of the eastern section .Subei is the first triple point of the west side, the region is located in the southwestern margin of Qilian fold belt, between the Qaidam Basin and Qilian Mountains,and the inside structure of the region is complex. For research in the area mainly concentrated in the Altun fault Subei fragment, while for the study of the area to the east Subei is relatively weak,basically in the blank. Four main faults in Subei: Yemahe-northern fault, the Yemahe-southern fault, the Subei-southwest thrust fault and Danghenanshan thrust fault,in addition, three faulting small-scale basin: Subeibasin, Yemahe basin and Yanchiwan basin. According to the currunt situation of research in the region, to carry out an investigation of the following contents :1) The relationship of regional tectonic features and textrue includes the distribution characteristics of water, ridges, basins, alluvial-proluvial fan, and the influence of tectonic activity to topography and landform.2) The important faults in the region are the Yemahe-northern fault, the Yemahe-southern fault, the Subei-southwest thrust fault and Danghenanshan thrust fault. Through field investigation, to keep track of the spatial distribution of fault and the geological features of these faults, to collect and analyze relevant information and revealthe late Quaternary fault activity.3) Through the study of the intraregional faults late Quaternary activity characteristic, and in combination with the research results of scholars in the other faults in this region, and the movement characteristics of intraregional main fault and conversion relations.Through field investigation and indoor analysis, combined with the existing data, the main conclusions:1) The Yemahe-northern fault r totally trends to 70°,is about 30km,which can be divided into East and West two geometric discontinuous paragraphs and the two paragraphs left-orderly array. The fault is a sinistral strike-slip and thrust active fault, the active faul mainly thrut up from the northern plate to the southern plate south to control the the north-west edge of Yemahe River Basin.T Yemahe-northern fault was a active fault since the Late Quaternary, the average rate of thrust was (0.4±0.07) mm / a, the average slip rate was (1.27±0.18) mm / a in the Late Pleistocene epoch.2) the Yemahe-southern fault spreads from east to west, with a total length of approximately 65km. The east and west sides of the faults exposed at the surface clearly thrust, has strike-slip geomorphology features and control the southern margin of the Yemahe River Basin.the Yemahe-southern fault was a more active fault since the Late Pleistocene. The average slip rate of the western part in the Holocene was 5.65±0.51mm / a,the thrust rate was 0.25±0.03mm / a. The sinistral average rate of the eastern section was 0.28±0.07mm / a,the thrust average rate was 0.11±0.02mm / a since the Holocene. The costean of eastern section revealed that the fault has the twice ancient seismic events.3) the Subei-southwest thrust fault overall was the anti-reverse "S" shape, the overall trend NWW, with the length ot approximately 17km.Along with the fracture,developed the more typical thrust topography, as well as exposed the fault profile, and the imbricate thrust was more development to control the southwestern margin of the Subei basin.the Subei-southwest thrust fault was a typical thrust fault, the thrust average rate was 0.86±0.16mm / a;the level of activity rate was relatively weak since the late Pleistocene.4) Danghenanshan thrust fault developed to the frontalzone of Dang-he-nan-shan mountain north side,whose overall trend was NW. Thrust fault was mainly reverse thrust,the south tray was northward thrust, wrong cut off the Holocene alluvial fan,and controlled the southwestern margin of the Yanchiwan basin. Since late Pleistocene , the averager reverse rate of the thrust fault was 0.04±0mm / a. The costean of northern section revealed that the fault has the twice ancient seismic events, the costean of the southern fault revealed that the fault has three times ancient seismic events.In Subei region, the decrease in the amount of exercise of the eastern section of the Altyn Tagh fault was decomposed three-part by tectonic movement, the reason was that:first, the Yemahe-northern fault and the Yemahe-southern fault was decomposd in the form of sinistral strike-slip and reverse thrust;second,the decomposition of the crustal shortening was caused by the up lifting and the thrust fault of Danghenanshan mountain;third,other structure in Subei areas,such as the decomposition of the activities of baisins and flod.Overall, the slip and reverse thrust rate of the main fracture of Subei is lower, the phenomenon of thrust-imbricated is relatively common, there are faults, basins, folds and other structures involved in the deformation and movement transform.These conclusions suggest that the extrusion rate and extent to east of the material is limited, in line with the "thrust imbricated conversion - limited extrusion model."...
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