Analysis of Sedimentary Environment of the Permian Lucaogou Formation in Southeastern Margin of the Junggar Basin

Using theories of classic sequence stratigraphy and modern sedimentology,the authors analyzed the data of drill holes,loggings,core with the purpose of investigating sedimentary environment characteristics and evolution of the Permian Lucaogou formation in the southeastern margin of the Junggar Basin.Based on sequence stratigraphic analysis of the single well,Lucaogou Formation is almost a complete third-order sequence,which is divided into lowstand systems tract,transgressive system tract,highstand systems tract and regressive systems tract,corresponding respectively to four lithologic sections of the stratum;According to the well-connecting profile,the authors established sequence stratigraphic framework,then combining with geological conditions of the basin,made a plane analysis of the sedimentary facies of each system tract.Lake facies is main type of systems tract in the area,which is divided into three subfacies-lakeside,shallow lake and semi-deep-deep lake,and then subdivided into four microfacies-sandy beach bar,muddy beach bar,carbonate beach bar and reef.