Structural Features And Their Evolution Of Late Paleozoic To Early Mesozoic Stratigraphy In Alake Lake-Hongshuichuan Area, East Kunlun Region

East Kunlun orogen is a compound continental orogenic belt which has undergone some multistage tectonic activities. Taking Mid-Kunlun fault and South-Kunlun fault as dividing lines, it can be divided into four belts from north to south, North Kunlun tectonic belt, Central Kunlun ophiolitic melange belt, South Kunlun tectonic belt and Buqingshan-A'nyemaqen tectonic melanges belt, respectively. Research area is located in the Alakehu-Hongshuichuan area of South Kunlun tectonic belt in the eastern East-Kunlun, and its tectonic evolution from late Paleozoic to early Mesozoic has a unique style, and it has close relationships with the spreading, subduction and collision of the north branch ocean of Paleo-Tethys. There exists great geological significance in studying the stratigraphic characteristics and tectonic deformation characteristics of the main structure rock stratigraphic unit, and its tectonic relationship with the formation and evolution of East Kunlun orogen.Based on macro mastering the latest research achievements and research progress of East Kunlun orogen and its adjacent regions, combined with wild-field geological profile, the paper puts the emphasis on collecting research achievements related with stratigraphy, petrology, tectonic geology and chronology in the research area, so as to analyze the tectonic deformation of strata from late Paleozoic to early Mesozoic. After analyzing the relationships between the tectonic geometry, and kinematic features of each stratigraphic unit and regional tectonic background, the paper has made a comprehensive research on tectonic deformation characteristics of Alakehu-Hongshuichuan area, so as to discuss its tectonic evolution.Based on systematically summarizing previous research achievements and analysis of wild-field survey and indoor comprehensive arrangement, the following cognitions are acquired in the paper on the research area's tectonic characteristics and tectonic evolution from late Paleozoic to early Mesozoic.1. Sedimentary strata from late Paleozoic to early Mesozoic in South Kunlun tectonic belt has been divided in detail, and initially established the stratigraphical sequence of this period.2. The study of the tectonic deformation and sedimentary environment of sedimentary strata between the Middle Triassic Naocangjiangou Formation and Later Triassic Babaoshan Formation in the research area, confirms that the angular unconformity formed between them has great significance for discussing the orogenic process and tectonic evolution and dynamic background of South Kunlun tectonic belt, even the entire East Kunlun orogen in this period. 3. With the analysis of the tectonic deformation characteristics of sedimentary strata from late Paleozoic to early Mesozoic, as well as combining different generations and multiples of tectonic styles (tight overfolds, inclined folds, large-scale folds), tectonic evolutionary sequence of the research area has been divided and initially established.4. Synthesizing regional geological information, tectonic evolution of the research area had undergone three stages from late Paleozoic to early Mesozoic. First stage is the spreading and opening up of Buqingshan-A'nyemaqen Paleo-Tethys, and the development of extensional rift extensional faulted depression of East Kunlun in the Devonian-Early Permian. Second stage is the subduction of A'nyemaqen Ocean beneath the East Kunlun block in late Early Permian-Middle Triassic. Intense tectonic compression and Later structure strengthening had caused fold deformation of strata in the Early-Middle Triassic. Third stage is the intercontinental collision orogenesis in the late Middle Triassic-Early Jurassic, which had caused regional unconformity between Lower Triassic and its underlying strata, and had caused the broad folds of the strata in the Late Triassic and Early Jurassic by a nearly N-S directed compression.