The Study On The Permian Strata In Huji'ertai Area Of Central Tianshan, Nileke County, Xinjiang

This dissertation is object on the sedimentary stratum of Permian period of Central Tianshan. Studying the features of strata in our researching area synthetically, including the field character, lithofacies, rock association,organic fossil analysis,contact relationship between the stratum and tectonics environment, et al. Through the several years of field survey and general research, gained the achievement as follows:1. We have not only clarified the relationship of contaction between the Permian strata and it's overlying strata, but also have understood the relationship of formations within Permian after field explorationIt and ba dao wan formation of Jurassic, which lays over it, contact With a fault and the rocks intruded the Permian at the bottom.2. A new formation named wulansayi has been found which belongs to the Early Permian.3. The wulansayi formation mainly formed the environment of shallow-water where ripples, rain and mud crack scar and other important deposition signs can be seen.The thickness of strata varys from west to east in region. The thinnest area is Longkou Station in gongliu which only exposed 21m, and the most thickness area lays huji'ertai in Nileke reaching 813.77m towards the east, then to the west(bayinjvlike in xinyuan county),it becomes thin. We think that the formation belongs the stable lacustrine deposits of the pan.4. The wulan formation of early Permian mainly contains the bimodal volcanic rocks which declare that the Yili basin was extruded and volcanic rift in continental crust appearsbecause of the post-collisional extension of the slack.5. Xiaoshansayi formation of Late Permian can be determined to belong to hot climate conditions of the oxidation of the river-the lake sediments temporarily according to the combination of it's clastic rocks , as well as the color, structure, construction, gravel sorting, rounding, primary sedimentary structures and secondary features.