基于RS和GIS的地质灾害易发性定量评价:以湖北省五峰县为例

根据地质灾害的群发性和区域性的特点,运用地质统计学理论,通过分析,选取研究区内致灾因子,采用信息量模型进行地质灾害易发性定量评价。文中采用地质统计学信息量法,以GIS技术和RS技术为基础,从致灾机理上对各致灾因子进行选取和分析,使用GIS空间分析技术,完成了地质灾害易发性分区定量分析。分析结果表明,研究区内:(1)软硬相间碳酸盐岩类、(2)与河谷距离50～350m的斜坡带、(3)软硬相间碎屑岩类、(4)公路两侧1km范围、(5)斜坡在断裂带影响范围以内(1km)、(6)与河谷距离<50m或350～550m等6大影响因子对地质灾害的发生起主导作用。其中,除"公路两侧1km范围"为人类工程活动外,其他因素均为地质动力作用。研究完成的五峰县地质灾害易发分区定量评价,为五峰县的经济发展和城镇规划提供了科学依据,同时为以后在鄂西南地区进行地质灾害遥感解译提供了参考。

Quantitative evaluation of geological disaster liability based on RS & GIS analysis:A case study of Wufeng County,Hubei Province

Geological disasters are more likely to happen in some specific areas and always followed by many other disasters caused by the happened geological disaster.It is applicable to quantitatively analyze the liability of geological disasters by using geological statistics and analyzing the factors that are responsible for the geological disasters under the information-scale model.In this study,we quantitatively analyzed the disaster-causing factors and their contribution to the disasters based on GIS and RS technology in Wufeng,Hubei Province.The results indicated that six main factors are mostly responsible for geological disasters in the investigated area:(1)the intercalation of soft-hard carbonates,(2)the slope belt 50350 meters away from the valley,(3)the intercalation of soft-hard clastic rocks,(4)the areas 1 kilometer flanking the road,(5)the slope belt within 1 kilometer away from the faults and(6) the areas within 50 meters or 350550 meters from the valley.Among these factors,"the areas 1 kilometer flanking the road" is an engineering activity and other factors belong to geological dynamic effects.In summary,our study quantitatively analyzed the liability of geological disasters in Wufeng,providing reference for the economic development and urban planning as well as for interpretations of geological disasters in southwestern areas of Hubei Province.