非完整滑坡编目三参数反Gamma概率分布模型  

Three-parameter inverse-gamma probability distribution model of incomplete landslide inventory

作　　者：胡元鑫[1] 刘新荣[1] 蒋洋[2] 葛华 

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]长安大学公路学院,陕西西安710064 [3]成都地质调查中心,四川成都610081

出　　处：《中南大学学报（自然科学版）》2011年第10期3176-3181,共6页Journal of Central South University:Science and Technology

基　　金：中国地质调查局项目(1212010914011)

摘　　要：中国"5.12"地震震级高,震源浅,于震区内触发了大量滑坡。为了研究地震滑坡的概率分布特征,对四川映秀极震区(约109.3 km2)地震滑坡进行系统编目,该编目属非完整滑坡编目。利用该编目建立三参数反Gamma概率分布模型,其拟合参数分别为b=1.11,a=2.17×10-3 km2及s=-3.925×10-4 km2。基于该模型对编目区内滑坡面积均值、总面积及最大滑坡面积进行计算,并引入滑坡标度及建立指数修正函数分别对"5.12"四川汶川地震触发滑坡总数及滑坡总面积进行预测,同时建议模型建立原则。研究结果表明:模型的幂律衰减参数值与已有研究结果相近;模型对编目区内滑坡面积均值、总面积及最大滑坡面积的计算结果与实测值之间的相对误差均为10%左右;模型对"5.12"汶川地震触发滑坡总数及滑坡总面积的预测结果均与已有研究结果比较接近。Because the ＂5.12＂ earthquake is of high magnitude and shallow hypocenter,it triggered a large number of landslides in seismic area.In order to research probability distribution of these earthquake-induced landslides,systematic earthquake-induced landslides inventory in Yingxiu meizoseismal area in Sichuan Province（about 109.3 km2）,which is an imcomplete landslide inventory compared with those throughout seismic area,was finished.On the basis of the incomplete landslides inventory,a three-parameters inverse-gamma probability distribution model was presented,in which the three parameters are b=1.11,a=2.17×10-3 km2,s=-3.925×10-4 km2 respectively.By means of the model,the mean,total and maximum landslide areas in inventoried area were calculated,and the total number and area of landslide triggered by the ＂5.12＂ earthquake were predicted by introducing landslide magnitude scale and exponential correcting function.Meanwhile,some suggestions for building three-parameters inverse-gamma probability distribution model were proposed.The results show that power-law decay parameters of the model are comparable to the previous research results.Computed relaive errors,with respect to the mean,total and maximum landslide areas in inventoried zone,are all about 10%.The total number and area of ＂5.12＂ earthquake induced landslide resulting from prediction of the model are both comparable to the previous research results.

关 键 词：滑坡编目 GAMMA函数 概率分布 “5.12”地震 四川映秀极震区 

分 类 号：P642[天文地球—工程地质学]