摘要
“5·12”汶川地震由于震级高、持续时间长、震区地质环境复杂，因而触发了大量的崩塌、滑坡。地震一年来，作者根据灾后对崩滑地质灾害的应急排查，并结合震后有限的ALOS、ASTER以及航空摄影等多源数据对地震重灾区的崩滑体数量进行了统计分析，获得确定性的崩滑灾害点有16704处，但是，由于排查范围及遥感数据的局限性，上述数据并不能代表这次地震触发崩塌滑坡总的数量。为了查明这个问题，本文在上述资料的基础上，采用不同烈度地区典型抽取样本统计的方法，获得了不同烈度区崩塌滑坡的发育密度，进而根据不同烈度区面积统计得出了本次地震触发崩塌滑坡数量的估计值，并与国际上若干大地震触发崩塌滑坡数量及分布面积进行了对比分析。最后，作者给出了灾区地震触发崩塌滑坡的密度分布图，并讨论了其分布特征。本文的研究结果表明：汶川地震触发的崩塌滑坡数量约为3．5万处，分布面积约为10×10^4km^2，发育密度最高在映秀一北川断裂上盘都江堰和彭州段以及沿岷江河谷的映秀一草坡段，约为5～6处／km^2。
Due to the high magnitude, long duration and complicated environment of the disastrous area, ＂5.12＂ Wenchuan Earthquake triggered a large number of collapses and landslides. By combining the post-earthquake emergency investigation of collapses and landslides with the limited multi-source data including ALOS, ASTER and aerial photos, etc. , during the past year after the earthquake, the author conducted the statistic analysis for the number of collapses and landslides in the serious earthquake area and confirmed 16704 collapses and landslides; but as the investigation range and remote-sensing data are limited, the ahovementioned data can＇t represent the total number of collapses and landslides triggered by this earthquake. In order to solve this problem, based on the obtained data, this paper adopted the method of drawing typical samples within the areas of different seismic intensity to calculate the development density of collapses and landslides within these areas, which is used together with the different acreage of these areas to obtain the estimated number of collapses and landslides triggered by this earthquake. The author also carried out a contrastive analysis to the total number and distribution area of collapses and landslides triggered by this earthquake with that of several large earthquakes in the world. At the end of this paper, the author compiled the density distribution map of earthquake-triggered collapses and landslides and explored its distribution features. The study result of this paper indicated that： the number of Wenchuan Earthquake-triggered collapses and landslides is around 35 000; the distribution area is about 100 000 km^2 ; and the highest density is 5-6 per km^2 within the Dujingyan-Pengzhou Section along Yingxiu-Beichuan fault and Yinxiu-Caobo Section along Minjiang River valley.
出处
《地质灾害与环境保护》
2009年第3期1-7,共7页
Journal of Geological Hazards and Environment Preservation
关键词
汶川地震
崩塌滑坡
数量
发育密度
遥感解译
Wenchuan Earthquake
landslides number
development density
remote sensing image interpretation
