Comparative Study Of Debris Flow Development Law In The Eastern Edge Of Qinghai-tibet Plateau Region

Xiaojiang River basin and Bailongjiang River basin lying in the eastern edge of Qinghai-Tibet Plateau is the areas where the debris flow is the most widely distributed and the largest and the most frequent occurred in China. With the uniqueness of its location, there are comparabilities to debris flow development law of the two river basin.The comparative study of debris flow activity law of the two river basin in the formation conditions and distribution of debris flow and Quaternary debris flow activity law in the ancient can help us better understand the relationship between the environment and the formation, distribution, evolution and future development trend of debris flow in the eastern edge of the Qinghai-Tibet plateau region,and provide direction for environmental management based on development for different regions of debris flow.Bailongjiang and Xiaojiang river basin not only develop the modern debris flow, but also the distribution of ancient debris flow deposits are also widespread. Bailongjiang and Xiaojiang River basin is located in ends of the border belt of China's north and south of landforms, but also located in the marginal zone of the monsoon, in order to provide favorable conditions for development of debris flow. In this paper, by analysis and comparison of two debris basins formed by internal and external motivation factors, the geological structure, the the intermittent uplift of new tectonic movement and human activities are stable environmental factors in many environmental factors. The years of poor temperature, lithology, slope conditions on the formation are more active to Bailongjiang valley debris flow, while the precipitation factors on the formation of debris flows in Xiaojiang River Basin are more active in Bailongjiang River Basin.The analysis of debris flow distribution characteristics of the eastern edge of Qinghai-Tibet Plateau region mainly compares the locations of two valley debris flow areas, the distribution density of debris flow, characteristics of the spatial distribution of debris flow ,characteristics of the distribution characteristics of debris flow occurred at a time, and reaches the relevance of these aspects in the two basins.Ancient mud-rock flow on the Quaternary research, the author mainly relies on sedimentary characteristics of the two basin of ancient mud-rock, landscape positions of terrace distribution and their relationships,with a number of dating data and literature analysis of the Quaternary basin of the two ancient mud-rock flow carried out in phases, the two Quaternary basin can be divided into eight ancient mud-rock flow. And by the new tectonic movement, terraces landscape and climate change during development of the debris flow and development of the relationship between the environment, combined with the evidence of the atmospheric circulation forms of Glaciation and Interglacial during the Quaternary,characteristics of sporo-pollen assemblage and total analysis of chemical element,the following conclusion will be given:in the Qinghai-Tibet Plateau Quaternary debris flow activity cycle, the Bailongjiang River debris flow activity cycle was mainly affected by climatic cycles of control, that is, debris Development was corresponding to the Interglacial or interstadial;Xiaojiang river valley debris flow activity cycle mainly was affected by the new tectonic movement of the control,that is,each new tectonic uplift of activity occurred intermittently after the debris flow activity began.