Analysis Of The Permian Sedimentary Facies In The Southern Turpan Basin, Xinjiang, And Its Southern Margin

Turpan basin is one of the three sedimentary basins in Xinjiang of our country, and also a basin with many kinds of energy and mineral resources symbiosis as oil, gas, coal and uranium. The industrial oil-gas store which was found in the pre-jurassic in the south of the basin in 1995 and very thick source rock series of the Permian found in the northern margin of the basin in recent years make the strengthening study of pre-jurassic and searching for pre-jurassic oil and gas reservoir become one of the main goal of Tu-Ha oilfield at present.The thesis is under the guidance of plate tectonic theory and theory activity of the continental dynamical study and on the basis of sedimentary petrology, paleontology, isotope geology, stratigraphy, sedimentology and other disciplines. Based on regional stratigraphic division and correlation, combined with orogenic belt and basin by the field outcrop, logging and seismic, the author comprehensively analysed the Permian sedimentary facies characteristics, types and its spatial-temporal evolvement the south and of Turpan basin in order to provide some reference basis for further exploration in this area.Therefore, based on the previous research, the author analysed and studied the drilling profiles and measured section in the south and Jueluotage orogenic belt in the south margin of Turpan basin according to lithologic characteristics, paleontologic characteristics and isotopic dating etc, and then determined the geological time. After that the author carried on the stratigraphic correlation of this area and analysed the Permian characteristics and its temporal-spatial variation of lateral and longitudinal. Then the author analysed the sedimentary facies of every single profile combined with the various kinds of facies marks, logging and seismic, and analysed vertical comparison and lateral distribution of the Permian sedimentary facies of this area, at last made sure the types of sedimentary facies in this area: littoral facies, neritic facies, fan delta facies, lacustrine facies and fluvial facies, etc. Among these, lowwer Permian mainly is littoral-neritic sea, fan delta and marine volcanic eruption lithofacies, which distributed in Tainan depression, Takequan salient, Dikaner area and its south, Huoshizhen depression, Xidagou in Yamansu and Xiaohuangshan in Hami, and Aqikebulake basin is filled with lacustrine sedimentary; middle Permian is lacustrine facies and fan delta facies in Tuokexun and Tainan depression, Huoshizhen depression is lacustrine facies and continental volcanic sedimentary; upper Permian is all continental sedimentary, Huashizhen depression comes out fluvial sedimentary, and Tainan depression is still fan delta facies and lacustrine facies, but the depocenter migrates to the north. Overall, the Permian in the south and the south margin of Turpan basin appears as several separate sedimentary fill in grabens and half grabens, this characteristic may also exist in the north depression of the basin.