Research On Morphological Identification Of Debris Flow Along The Main-Road In The Border Area Of Hubei-Henan-Shanxi Provinces

Debris flow develops with the mountainous geomorphic evolution process. To identify debris flows velley, means to distinguish debris flow from general gully valleys scientifically. Based on the theory of geomorphic information entropy and the analysis of the relationship between New-tectonic Stress Field and debris flow activities, have made some research on the morphological identification of debris flow. The main results obtained are as follows:1. According to the valley-data collected along the main roads in the border area of Hubei-Henan-Shanxi provinces, the area-altitude information can be revealed. For each valley, the entropy value can be calculated and the dangerous standard can be advanced based on the above information. The New-tectonic Stress Field has some affection on the development of the debris flow. The characteristic of the stress field has been studied with the back-stepping of the local river system. Compared the characteristic with the distribution features of the valleys, the potential debris flow have been found. With the synthetically analysis of the results from geomorphic information entropy and New-tectonic Stress Field, the identification of debris flow can be realized.2. After quantizing the valley data, the area-altitude information and entropy value have been taken. The values range from 0.053 to 0.441——basically at the infancy- manhood development stage, and the mid-value is 0.25——at the early stage of manhood. For the valleys, the"Division standard of dangerous level"can be raised up with the further consideration of the actual situation. The standard can be used to divide the different valleys with different standard. If the E-value is smaller than 0.25, the related valley would be viewed as dangerous. After summarization, there are 62 dangerous valleys which are mainly distributing along G316(26) and G209(23), and respectively 2 and 11 along G207 and G311.3. The New-tectonic stress field has been back-stepped with the study of the local river system——the local principal compressive stress is NW[5°,0°)(σT), and the two shear zone directions are NW(45°,40°](Max1) and NE[35°,40°)(Max2) respectively. For each valley, the information of the strike and area can be figured out and use to draw the rose map. The rose map would reveal the characteristic of the valley distribution which is intensively in the direction of NE[0°, 40°), and one of the dominant directions is NE[0°,10°)(α1) and the other is NE[30°,40°)(α2).α2 is next to the Max2 and the valleys which distribute in this direction are weakly-developing and easily suffered from soil and water loss. Therefore, they would be viewed as potential debris flow and are counted to 10 totally which are mainly distributing along G316(6) in Yun county, Shiyan city, Hubei province and the South of Shanxi. And for G209 and G311,there are 2 respectively.4. With the comprehensive consideration of the results from the geomorphic information entropy and the New-tectonic stress field, there are 9 common valleys which can be viewed as debris flow.