时空维度降雨对碳酸盐岩地区崩塌的影响

Influence of rainfall on rockfall in the area covered with carbonatite by time and space dimensions

我国地质灾害的分布具有点多面广等特点,崩塌是我国主要的地质灾害类型之一,降雨是引发崩塌发生的主要自然因素之一。为了解降雨对靖西市碳酸盐岩地区崩塌的影响,从而指导靖西市碳酸盐岩地区的防灾减灾工作,保护人民的生命财产安全,开展了此次研究。通过从时间、空间两个维度,研究广西壮族自治区百色市靖西市的碳酸盐岩地区的降雨对崩塌的影响,利用线性回归分析,我们发现,在时间维度上,在降雨量较大的6、7月份,崩塌发生次数也较多;在空间维度,降雨量较大的区域,崩塌的密度也较大,但在一些降雨量较小的区域,地质灾害点密度也可以达到峰值。这意味着,在降雨量预警划分时,可将靖西市碳酸盐岩地区划分为3个区域,即I区(北部魁圩乡—果乐乡—新甲乡—渠洋镇)、II区(吞盘乡)和III区(I区II区之外的其他乡镇)。其中I区的降雨预警值可在1400 mm左右、II区在1500 mm、III区在1700 mm。

Large quantity and widely distribution are the distinguishing features of geological hazard in China.One of the major types for geological hazard in China is rockfall.Rainfall is the main natural factor that affect the stability of rockfall.In order to study influence of rainfall on rockfall in the area covered with carbonatite,we carried out this study.This study can guide disaster prevention and reduction,and protect people’s life and property.The area covered with carbonatite,where is in Jingxi,Baise,Guangxi Zhuang Autonomous Region,is the focus of this research.By using the linear regression of rainfall and the number of rockfall,we find that in the months with larger rainfall,the more numbers of rockfall happened from time dimensions.And from time dimensions,there are more number of rockfall in rainy area.However,in some areas with small rainfall,the density of rockfall can also reach the peak.That means the carbonate area of Jingxi could be divided into three areas according to rainfall.Rainfall threshold of Zone I,where is in Kuixu,Guole,Xinjia and Quyang area,is 1400 mm.Rainfall threshold of Zone II,where is in Tunpan area,is 1500 mm.Rainfall threshold of Zone III,where is in Ande,Longlin,Ludong,Xinjing,Wuping,Tongde,Nanpo,Huadong,Dizhou,Anning,Longbang,Yuexu and Hurun area,is 1700 mm.