论文部分内容阅读
选择地震极重灾区(都汶公路沿线)作为研究区域,利用遥感影像解译和野外调查数据,采用信息量方法,分析地震崩塌滑坡对影响因子的敏感性,结合GIS技术评价地震崩塌滑坡的危险性。研究表明,都汶公路沿线最利于地震崩塌滑坡的条件为:(1)坡度:大于35°;(2)坡向:E,ES和S坡向;(3)坡面粗糙度:大于1.15;(4)距断层距离:5～20km;(5)土地利用类型:林地、灌木林地和疏林地;(6)地层岩性:元古代闪长岩、元古代斜长花岗岩、元古界玄武岩、安山岩、石炭系灰岩、泥灰岩和志留系灰绿色千枚岩及石灰岩,尤其是元古界玄武岩和安山岩。利用信息量综合因子叠加技术,对研究区域崩塌滑坡体进行危险性评价,并将其分为极高度危险区、高度危险区、中度危险区、轻度危险区以及基本无危险区。危险性评价结果表明:研究区域大部分处于中度危险区、高度危险区、极高度危险区,三者面积占总面积的70.34%,其中极高度危险区占到总面积的19.15%,范围较大,在公路修复和重新规划建设中应加强预防这些区域发生崩塌滑坡;基本无危险区范围较小,仅占总面积的11.81%;在分布特征上,极高度危险区和高度危险区主要分布在映秀至草坡河段上,草坡河至汶川段大部分处于轻度危险区及以下。研究结果可为震后公路恢复、重建及灾区重建提供科学指导与技术支持。
Seismic disaster-stricken lands (along the Du-Wen highway) are selected as research areas. Using remote sensing image interpretation and field survey data, the information method is used to analyze the sensitivity of seismic collapse landslides to impact factors. GIS is used to evaluate the danger of earthquake landslides Sex. The results show that the most favorable conditions for landslides along the Du-Wen Highway are as follows: (1) Slope: more than 35 °; (2) Slope: E, ES and S; (3) Slope roughness: more than 1.15; (4) Distance from fault: 5 ~ 20km; (5) Types of land use: woodland, shrubbery and sparse woodland; (6) Stratigraphic lithology: Proterozoic diorite, Proterozoic plagiogranite, Proterozoic basalts, Andesite, Carboniferous limestone, marl and Silurian gray-green phyllite and limestone, especially Proterozoic basalts and andesite. The risk assessment of landslides in the study area is carried out by using the information factor comprehensive factor superposition technique and divided into extremely high, moderate, moderate and basic non-hazardous areas. The results of risk assessment showed that most of the study areas were in moderately dangerous areas, highly dangerous areas and extremely highly dangerous areas, accounting for 70.34% of the total area, of which the extremely dangerous areas accounted for 19.15% of the total area, Large, in highway repair and re-planning and construction should be strengthened to prevent landslides in these areas; the basic non-hazardous area is small, accounting for only 11.81% of the total area; in the distribution characteristics, the main distribution of highly dangerous and highly hazardous areas From Yingxiu to Caocao River, most of Caocaohe to Wenchuan are in mild danger zone and below. The results can provide scientific guidance and technical support for post-earthquake highway rehabilitation, reconstruction and disaster area reconstruction.