Late Paleozoic Geological Characteristics And Its Evolution In Dabancheng Area,

Study area is located around Dabancheng that is in Urumqi city of Xinjiang, it belongs to the western of Bogda Orogen, Carboniferous-Permian strata and intrusive rocks are developing in this area, it is the best area for researching Late Paleozoic strata, intrusive rocks and tectonic evolution along the Bogda. Previous data in the aspects of the stratum, intrusive rocks, tectonic was limited to " Bogda 1:20 000 geological surveying and prospecting ", the degree of study at this place was lower, even stratigraphic classification system of previous study and current " Xinjiang Uygur Autonomous Region lithostratigraphic " is inconsistent, therefore, it requires further refinement. On the basis of achievement of previous research and project in Dabancheng area, according to the guidance of the plate tectonics and orogenic belts theory, we studied rocky formations, depositional environment and relations between the groups and geochronology systematically in this area, we established stratigraphic system, and divided the Late Paleozoic strata in the study area into six groups, they are Liushugou Late Carboniferous, Late Carboniferous Kier Gus set, Late Carboniferous group before Gap, Gap group after the Late Carboniferous and early Permian Dan Renzi ditch group,and the two groups Stones Tash Kula;We have conducted a systematic study of petrology,geochemistry and geochronology in this area, have built intrusive rock sequences which are Late Carboniferous and Middle Permian, and have discussed evolution, evolution order, forming background and emplacement mechanism of intrusive rock in each sequence; on the basis of systematic study and comparison of regional stratigraphy, intrusive rocks, refined stratigraphy and intrusive rocks in the research area,, we have explored late Paleozoic geological evolution, and reclassified Ⅳ-level stratigraphic area along Dabancheng into Bogdo area and Yilianhabierga area, and Ⅳ-level structural unit was redistributed into Bogda late Paleozoic rift valley and Bayingou late Paleozoic chasmic trough. This research has great theoretical significance for redefinition of researching basic geological issues and better understanding of structure and evolution around Bogda area, it also has important guiding role for further prospecting and doing some geological work in this research area later.