Analysis On The Age Of Dali Fossil From The Perspective Of Regional Landscape Evolution

To explore the history of ancient human evolution is an issue that has been paid attention to by the paleoanthropologists. Previous studies showed that ancient human evolution is mainly divided into four stages: Homo habilis, Homo erectus, early Homo sapiens, and late Homo sapiens. Dali Man as early individual of early Homo sapiens. It features to reveal Homo erectus and Homo sapiens conversion to the stage is significant. Since the Dali Man found that the scholars interested in the study. Previous studies, on the one hand, the loess-paleosol sequence covered with the fossil layer is used to infer the age; on the other hand, it is a physical dating of the fossils in the same layer of fossils. So far, the academic circles have not formed a unified view on the study of its age. Therefore, this article based on the history of the regional geomorphic-sedimentary evolution analysis of ancient human activities.In order to achieve the purpose of this research is needed to understand the lacustrine deposits and loess deposits in the area. When investigated the line of Luohe River and Jinshui valley, and we selected some deposition profiles to sample, such as Dongyao, Xihuacheng, Jiefang, Fulifang, Xiaxinzhuang and so on. According to the Loess-paleosol sequence dating method, the Paleo magnetic dating and Magnetic susceptibility, analysis of the characteristics of geomorphic-sedimentary bodies, to clarify the stages of Quaternary the history of the regional geomorphic-sedimentary evolution. The research result shows that Jinshui valley in the S14, L9, L6, S2 and L2 development and accumulation occurred a large lake back of five times. Luohe River happened only three times due to near the paleo lake center when L6, S2 and L2 developed or accumulated respectively. Each time the lacustrine deposit is exposed to the surface of the lake, the deposition layer accepted the loess-paleosol, and then it will be a slow process. Regional geomorphic-sedimentary profiles indicated that the past paleo lakes have the stage characteristics of Lake Regression and Lake Invasion.By investigating of the key Jiefang village, the author has suggested that the formation of this section is divided into three parts: the upper part of the loess paleo sol deposits, central lacustrine sediment and lower river sediments. The result shows that the magnetic susceptibility data indicated the profile of the oldest loess in this section is S2. The grain size curve showed that the profile was the positive rhythm of the upper fine and the lower rough. And that the sandy-gravel sediment from which the fossil was discovered was deposited after the paleo lake regression at the late stage of the deposition of L6. Combined with the palynological studies of Sun Jianzhong about Dali Man Site Profile, Megaloceros pachyosteus, Megaloceros giganteus and Gazella przewalskii, Herbaceous plant with the Dali Man layer during the same period. Reflect the environment of ancient human life was humid, semi-humid climate. Paleoclimate records of Dali Man Site Profile of the sporopollen diagram reflect the dry and cold to warm and wet climate change and the loess-paleosol is corresponding. Thus, the deposition of the alluvial sediment is probably synchronous with the formation of S5. About S5 age, according to the different methods of the average age of about 0.53 MaB.P..From biological skull morphology study showed that Dali Man’s evolution to a greater extent than pekinensis, namely time to later than pekinensis. At present, the academic circles of pekinensis lived in the 0.42~0.50 Ma B.P. to the majority view, but Shen in 2009 on the Nature of pekinensis age proposed new ideas: 0.77 + 0.08 MaB.P.. This paper about Dali Man age(0.53 MaB.P.) identify with the age of the new framework.