摘要
Abstract
To explore the spatiotemporal distribution patterns of regional geological disasters,we took 767 hidden danger points and 457 disaster points induced by rainfall as samples and used the frequency ratio model to analyze the control patterns of 9 environmental geological factors and rainfall on disasters in the Lveyang-Ningqiang area of southern Shaanxi Province.We obtained the following conclusions:The factors related to roads,rivers,and elevation have a significant controlling effect on disasters.These factors affect the physical and mechanical properties of surface rock and soil masses.Among them,the relationship between elevation and the spatial probability of disasters satisfies an exponential function.The relationships between slope,NDVI and the spatial probability of disasters satisfy a gamma function and a Gaussian function,respectively,while the relationships between roads,rivers,building density and the spatial probability of disasters satisfy a linear function.Rainfall-induced geological disasters in the study area show a characteristic of clustering.Nine relatively strong rainfall events have induced 76.15%of the disasters.With the increase of rainfall intensity,the proportion of rainfall duration in the disaster-causing process gradually decreases.For more intense disaster-causing rainfall,the role of effective rainfall amount becomes more significant.关键词
地质灾害/环境地质因子/时空概率/降雨阈值Key words
Geological disaster/Geological environmental factors/Spatiotemporal probability/Rainfall threshold分类
天文与地球科学
