摘要
以延安市13个县区地质灾害详细调查成果为基础,对区内滑坡进行了统计分析,并采用ArcGIS软件将滑坡叠加在地形图中,研究了区内滑坡的时空分布规律和发育特征。研究表明,空间上,北部砂黄土地区滑坡发育数量明显比南部壤黄土地区多,滑坡在一、二级河流河谷区两侧及多条河流交汇处集中分布,阴坡发生滑坡的比率高于阳坡,滑坡在年降雨量多的地区集中分布,在人口和交通工程密集区域内集中分布;时间上,滑坡在6-9月份的雨季相对集中,在晚更新世末和全新世初期相对集中。其发育特征表现为:区内滑坡有7种类型,但以黄土滑坡(黄土内滑坡、黄土与红黏土接触面滑坡、黄土与基岩接触面滑坡、沿古土壤面滑坡)为主,滑坡体长度主要集中在6~300m,宽度主要集中在15~300m,厚度主要集中在1~20m,滑坡体面积在0.009 6×10~4~40.5×10~4 m^2之间,体积在0.026 88×10~4~1 620×10~4 m^3之间,其中以中小型滑坡为主;提出了因地制宜的针对性建议,为区域内的防灾减灾工作提供了一定的参考。
Based on the detailed investigations of geological disasters of 13 counties in Yan＇an, the spatial and temporal distribution and development characteristics of the landslides were studied by the statistical a- nalysis and overlay analysis on the topographic map through the software of ArcGIS. The results show that the number of landslides in the northern sandy loess area is obviously larger than that in the southern loam soil area spatially. Moreover, the landslides are centrally developed in the both sides of the first or second river valley and the interchange of many rivers. In addition, the rate of occurrence of landslides in shady slope is higher than that in the sunny slope. Landslides are also centrally developed in the areas with more rainfalls and more population and transportation engineering. Most landslides often occurred during the rainy season from June to September, also concentrating in the late Pleistocene and early Holocene strata. There are 7 types of landslides in the study area, dominated bythe loess landslides,including loess landslides, loess-red clay landslides, loess-rock landslides and loess-paleosol landslides. The landslide was mainly 6--300 m long, 15--300 m wide, and 1--20 m thick. The landslide covered an area between 0. 0096 ×10^4m^2 and 40.5×10^4m^2, with the volume between0.026 88×10^4m^3 and 1 620×10^4m^3. The small and medium-sized landslides were in the majority. According to the results, specific suggestions are made for local conditions, with some references for disaster prevention and mitigation in the region.
出处
《地质科技情报》
CAS
CSCD
北大核心
2017年第2期236-243,共8页
Geological Science and Technology Information
基金
国家自然科学基金项目(41502278)
关键词
延安市
滑坡
时空分布
发育特征
防灾减灾
Yan＇an City
landslide
spatial and temporal distribution
development characteristics
disaster prevention and mitigation
