彝良地震地质灾害特征及其空间分布分析  

CHARACTERISTICS OF GEOLOGICAL HAZARDS IN YILIANG EARTHQUAKE AND STATISTICAL ANALYSES OF THEIR SPATIAL DISTRIBUTION

作　　者：冯新科 李志强[1] 李晓丽[1] 汪明朕 

机构地区：[1]中国地震局地质研究所,北京100029

出　　处：《地震地质》2015年第2期555-564,共10页Seismology and Geology

基　　金：中国地震局地震行业科研专项(2013080185)资助

摘　　要：2012年9月7日11时19分和12时16分在云南省彝良县与贵州省威宁县交界处相继发生5.7级和5.6级地震（简称＂9·07＂彝良地震）,此次地震诱发了大量的次生地质灾害,文中基于现场调查和遥感影像目视解译的方法得到了彝良地震地质灾害的空间分布图,并对其分布特征做了分析。统计结果表明,此次地震诱发的地质灾害约213处,总面积约为0.67km2,地质灾害类型多样,但以崩塌、滚石为主。利用GIS空间分析功能,对此次地震诱发地质灾害的所在烈度区、地层、坡度和距水系、道路的距离等5个影响因子进行统计分析,深入揭示了影响因子对地震诱发地质灾害的控制作用。结果表明,此次地震诱发的次生地质灾害：1）多发生于沿洛泽河一带的石炭系内;2）多发生在Ⅷ度区内,且与烈度呈正相关关系;3）主要分布在坡度20°~50°范围;4）密集发生在距水系、道路的距离为500m内的区域,且与距水系、道路的距离呈负相关关系。On September 7, 2012 at 11：19 and 12： 16（Beijing time） , two catastrophic earthquakes with Ms5.7 and Ms5.6 struck the junction area of Yiliang County, Yunnan Province and Weining County, Guizhou Province, China. The research result indicates that the September 7, 2012 Yiliang earthquake triggered a mass of secondary geological disasters. The spatial distribution of the Yiliang earthquake triggered geological disasters is presented in this paper, by field check and using visual interpretation of remote sensing imageries. The statistical analyses results of their spatial distribution indicate that there are about 213 geological hazards throughout an area of about 0.67km^2, consisting of collapse, landslide, rolling stones and mud-rock flow etc. We analyzed five characteristic parameters of these geological disasters triggered by Yiliang earthquake using GIS spatial analyses, such as seismic intensity, the formation stratum, slope angle, distances to river system and distances to road, and investigated in depth the control effect of these influence factors on the earthquake- induced geological hazards. This study reveals that： 1） most of the earthquake-induced geological hazards occurred in the Carboniferous strata along the Luoze River; 2）seismic region with intensity V$ within the study area is the high incidence area of geological disasters, and the geological hazards have positive correlation with seismic intensity; 3）the hazards are mostly distributed in the slope range between 20° - 50° ; 4） geological disasters are densely distributed in the distance of 500m to river system and road, and they have negative correlation with the distance.

关 键 词：彝良地震 地质灾害 GIS空间分析 

分 类 号：P315.9[天文地球—地震学]