Carboniferous-Permian Tectonic Evolution Analysis Of Turpan-Hami Basin

Turpan-Hami Basin is located in east Xinjiang, in the middle of Kazakhstan plate, Siberian plate and Tarim plate.lt is an important oil and gas basin in west China. Carboniferous and Permian shows good exploration prospects. Due to the low level of exploration, complexity of tectonic evolution,tectonic evolution of Turpan-Hami Basin from Carboniferous to Permian is not known completely, so it is necessary to do research.The study is based on seismic and geologic data, through collecting comprehensive geophysical data, geological outcrop data, drilling data and other relevant sedimentary information analyzing tectonic setting and sedimentary environment, dividing tectonic evolution stage, prototyping basin grid, analyzing tectonic stress field, typical cross-section and related tectonic belt of the basin, at last, tectonic evolution characteristics and laws of the basin in each period is summarized.Conclusions are as follows:(1)the overall tectonic evolution stages of Turpan-Hami basin is divided into:①C1-P1, stretching rift developmental stage, ② P2-T, developmental stage of foreland basin, ③J-K-E, formation evolutionary stage of wide basin, ④N-Q, regeneration foreland basin stage. The Carboniferous-Permian period can be divided into 5 phases: ① Early Carboniferous:rift and arc collision developmental phase, ② Late Carboniferous:extension phase, ③Farly Permian: collision extension phase after collision, ④Middle Permian:extrusion phase (reverse phase), ⑤Late Permian:the inland extrusion phase. (2)Turpan-Hami Basin is in the north-south extensional stress field from Carboniferous to Early Permian, and since Early Permian it is in a north-south compressional stress field. (3)Carboniferous to Early Permian is marine sediments, and it change into continental sediments since Middle Permian. (4)Tectonic belt around Turpan-Hami Basin controls differences between north and south, east and west:Turpan Depression(west) formatted earlier than Hami Depression(east) and Liaodun Uplift, and it moves stronger than Hami Depression; The north of Turpan-Hami Basin moves intense and late,while the south is more gentle and earlier,and the north and south has different provenance.(5)tectonic movements in different period controls evolution of Turpan-Hami Basin:Middle Hercynian determines extensional tectonics, Late Hercynian performances uplift tectonic; influenced by Late Hercynian uplift and Late Triassic, Permian sedimentary sequence is not complete, mainly stays in the central and northern part of the basin, Carboniferous and Permian is thick in north and thin in south.