岷江上游寿江流域地质灾害危险性分析

发布时间：2018-05-13 01:34

本文选题：地质灾害发育特征 + ArcGIS　；参考：《成都理工大学》2017年硕士论文

【摘要】：寿江流域地处四川省北西部阿坝州汶川县南部,位于邛崃山系、龙门山系之间,系岷江右岸一级支流。区内地质条件复杂、新构造运动强烈、降雨丰富,地质灾害频发,特别是滑坡、崩塌及泥石流地质灾害发育规模大、频率高,严重阻碍、威胁到区内的经济建设以及人民群众的生命财产安全。因此,进行寿江流域地质灾害调查及危险性评价,以期对寿江流域防灾减灾提供有效支撑。本文在结合资料收集和野外实际调查的基础上,以寿江流域92处地质灾害为研究对象,深入分析地质灾害的分布规律、发育特征、形成影响因素,结合层次分析法、信息量法,基于ArcGIS平台,完成寿江流域地质灾害危险性分析及区划,取得的主要成果如下:(1)寿江流域位于龙门山构造带南端,地势整体西高东低,区内出露马尔康分区部分地层、龙门山及四川盆地分区地层,区内降雨丰富。在这种地质环境背景下,发育了43处滑坡,41处崩塌,8处泥石流。(2)通过对寿江流域地质灾害调查、分析,得到以下结论:(1)从时间来看,寿江流域地质灾害发生频率最高主要在每年的5~9月份,尤其是6、7、8月份;(2)从空间分布来看,滑坡灾害主要分布在漩口~水磨~三江地区,且河流左岸比右岸多;崩塌灾害主要分布在三江上游的黑石江、中河及西河两岸,规模以大型、特大型为主;泥石流灾害主要分布漩口~水磨~三江地区,类型主要为山区强降雨诱发形成的暴雨型泥石流,规模主要为大中型。(3)通过ArcGIS平台,建立寿江流域地质灾害个人数据库。运用ArcGIS的空间分析功能,对寿江流域地质灾害形成影响因子进行统计分析,得出最有利于地质灾害发生的因子组合。统计分析表明:(1)滑坡灾害在坡度为20~40°、软硬相间的碎屑岩地区、降雨量为1050~1075mm范围内敏感性最强;(2)崩塌在坡度为40~60°、坚硬岩浆岩地区、降雨量为1000~1025mm范围敏感性最强;(3)泥石流在20~40°、软硬相间的碎屑岩类、降雨量为1025mm之上敏感性最强。(4)运用基于层次分析的信息量法确定评价因子的信息量权值。通过构建四级指标的层次结构确定评价因子权重,运用信息量法计算各指标对应的信息量权值,并在ArcGIS中对各评价单元进行信息量赋值。(5)基于Arc GIS平台的空间加权总和叠加功能完成寿江流域地质灾害危险性评价与区划,并将危险区分为四个等级及所占面积百分比:低危险区(43.02%)、中危险区(21.67%)、高危险区(18.47%)、极高危险区(16.84%)。(6)利用ROC曲线法,将研究区危险性区划与已知的地质灾害点比较,验证地质灾害危险性评价的预测结果。结果表明,基于信息量法的ArcGIS地质灾害评价结果有较高的准确性,可将其应用到寿江流域的地质灾害危险性评价中。
[Abstract]:The Shoujiang River Basin is located in the south of Wenchuan County of Aba Prefecture in the north west of Sichuan Province. It is located in Qionglai Mountains and between the Longmen Mountains and is a first grade tributary on the right bank of Minjiang River. The geological conditions in the area are complex, the neotectonic movement is strong, the rainfall is abundant, the geological disasters occur frequently, especially the landslide, collapse and mud-rock flow geological hazards have a large scale, high frequency and serious obstacles. It threatens the economic construction of the region and the safety of the people's lives and property. Therefore, the geological hazard investigation and risk assessment in Shoujiang River Basin are carried out in order to provide effective support for disaster prevention and mitigation in Shoujiang River Basin. On the basis of data collection and field investigation, this paper takes 92 geological disasters in Shoujiang River Basin as the research object, deeply analyzes the distribution law, developmental characteristics, forming factors of geological disasters, and combines the Analytic hierarchy process (AHP) and the method of information quantity. Based on the ArcGIS platform, the geological hazard analysis and zoning of the Shoujiang River Basin are completed. The main results are as follows: the Shoujiang River Basin is located at the southern end of the Longmen Mountain structural belt, with the overall topography being low in the west, high in the east and low in the east, and part of the strata in the Lomalkang subzone is located in the area. Longmen Mountain and Sichuan Basin zoning stratigraphy, rich rainfall in the region. Under the background of this geological environment, 43 landslides, 41 landslips, 41 landslides, 8 debris flows and 2) through the investigation of geological hazards in the Shoujiang River Basin, the following conclusions can be drawn: 1) from the time perspective, The frequency of geological hazards in Shoujiang River basin is the highest in May and September of each year, especially in July and August. According to the spatial distribution, the landslide disaster is mainly distributed in the area of Whirlangkou ~ Shuimo ~ Sanjiang River, and the left bank of the river is more than that of the right bank. The collapse disasters are mainly distributed in the upper reaches of the three rivers, the Heishi River, the Middle River and the West River, with a large scale and a large scale; debris flow disasters are mainly distributed in the area of maelstrom to Sanjiang. The main types are heavy rainfall induced torrential rain debris flow in mountainous areas, the scale of which is mainly large and medium. (3) through ArcGIS platform, the personal database of geological hazards in Shoujiang River Basin is established. By using the spatial analysis function of ArcGIS, the factors affecting the formation of geological hazards in the Shoujiang River basin are statistically analyzed, and the most favorable combination of factors for the occurrence of geological disasters is obtained. The statistical analysis shows that the landslide disaster in the area of soft and hard clastic rock with a slope of 20 ~ 40 掳and rainfall of ~ 60 掳is the most sensitive in the range of rainfall within the range of 1050~1075mm) and the landslide is in the area of hard magmatic rock with a slope of 40 ~ 60 掳. Rainfall is the most sensitive in the range of 1000~1025mm.) debris flow is at 20 掳40 掳, soft and hard clastic rocks, and rainfall above 1025mm is the most sensitive. 4) Information quantity method based on AHP is used to determine the information weight of evaluation factors. The weights of evaluation factors are determined by constructing the hierarchical structure of the four levels of indicators, and the corresponding weights of each index are calculated by the method of information quantity. Based on the spatial weighted summation superposition function of Arc GIS platform, the risk assessment and regionalization of geological hazards in Shoujiang River Basin is completed. The dangerous area is divided into four grades and the percentage of area: low risk area (43.02o), middle risk area (21.67m), high risk area (18.47m), extremely high risk area (16.84g). (6) using ROC curve method, the risk zoning of the study area is compared with known geological hazard points. Verify the prediction results of geological hazard risk assessment. The results show that the evaluation results of ArcGIS geological hazards based on the information quantity method have high accuracy and can be applied to the risk assessment of geological hazards in the Shoujiang River basin.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P694

【参考文献】