【作者】 梁健坤；

【导师】 陈洪凯； 唐红梅；

【作者基本信息】 重庆交通大学 ， 自然地理学， 2011， 硕士

【摘要】 泥石流沟的发育与山地地貌演化过程有很大的关系。泥石流沟的判识,是要科学区分泥石流沟和一般的沟谷(洪水沟)。本文基于地貌信息熵理论,以及对新构造应力场与泥石流活动的关系的探讨,对泥石流沟的地貌学识别进行了研究,取得的主要成果如下:1.对鄂豫陕交界区主要公路沿线的沟谷信息进行了提取。根据地貌信息熵理论,对所有沟谷的面积-高程信息进行了分析和统计,得到了相应的地貌信息熵值以及危险程度划分标准,并进行了沟谷危险程度的划分。考虑新构造应力场对泥石流灾害的宏观影响特性,采用水系反演法得到了区域应力场的基本特征,并与沟谷的分布特点进行比较,得到了潜在泥石流沟的分布。综合考虑地貌信息熵与新构造应力场的共同作用效应,实现了双因子条件下的泥石流沟的地貌学识别。2.对提取到的沟谷进行了地貌信息的量化,分别求算了每一条流域的面积-高程积分以及地貌信息熵值。研究区内各条沟谷的地貌信息熵值范围为:0.053-0.441;基本处于地貌发育的幼年期-壮年期阶段。对地貌信息熵值求取中值,结果为:0.25,处于壮年发育期的早期阶段。结合研究区的实际情况,提出了“鄂豫陕交界区公路沿线危险沟谷划分标准”。对鄂豫陕交界区内主要公路沿线不同危险程度沟谷进行了划分:将E值小于0.25的沟谷视为危险沟谷,共计62条,主要分布在G316沿线(26条)与G209沿线(23条),而G207与G311沿线则分别有2条和11条。3.利用水系法反演了研究区的新构造应力场:第一组优势方向(Max1):NW[45°,40°);第二组优势方向(Max2):NE[35°, 40°);区域主压应力方向σT=NW[5°,0°)。对各条沟谷的轴线走向及相应的流域面积进行了统计,并绘制了流域分布玫瑰图以做分析:沟谷集中分布在NE方向,区间为NE[0°,40°);流域分布的第一组优势方向α1为NE[0°,10°),第二组优势方向α2为NE[30°,40°)。α2与Max2剪切带方向基本一致,是地表的软弱带,沿该方向带展布的沟谷在易于发生水土流失,可以将其判识为潜在泥石流沟——共计10条,集中分布在湖北省十堰市郧县和陕南地区的G316沿线(6条),豫西的G209与G311沿线各有2条。4.综合考虑地貌信息熵理论的分析结果与新构造应力场的作用效应,将判断出的共同沟谷识别为泥石流沟——共计9条。更多还原

【Abstract】 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.更多还原