摘要
The well-preserved Neoproterozoic Nanhua stratum in the Keguqinshan area of Yili,Western Tianshan can be divided into Kulutieliekti Formation,Tulasu Formation and Biexibasitao Formation from bottom to top,which may represent the deposition during two ice age events and an interglacial period.The lowest Kulutieliekti Formation is mainly composed of till conglomerates and pebble-bearing tuffs.Biexibasitao Formation mainly consists of till conglomerates and pebble-bearing tuffaceous lithic sandstones.The Tulasu Formation,as the interglacial deposit is mainly composed of siltstone and fine sandstone and tuffs.Based on the study of lithofacies paleogeography,the Nanhua system in the study area is considered to represent a neretic environment along with glaciations and volcanic activities.Therefore,it can be divided into three facies,i.e.glacial sedimentary facies,marine facies and volcanic eruption facies.Moreover,the glacial sedimentary facies can be further divided into basal tillite subfacies,proglacial littoral subfacies and ice rafting neritic subfacies,while the marine facies can be divided into neritic detrital subfacies and neritic carbonate subfacies.In addition,compare the Nanhua system in the Kuluketage region with the Nanhua system in the study area of this article.