地震和降雨耦合灾害分布与长期活动性分析

震后灾区强降雨诱发的地质灾害造成了灾难性损失,成为灾区新的威胁。通过对西昌7.5级地震灾区鹅掌河流域进行灾害分布特征和主控因素进行分析,研究表明:1流域内灾害具有地震灾害效应。灾害表现为沿断裂带呈条带分布且集中于东盘,地层倾向性,滑坡堰塞形成S型河道,微地貌效应和灾害链式效应。2区域内7.5级地震后以中小地震为主,降雨量变化平稳。灾害具有长期活动性,表现为崩滑的频繁发生,鹅掌河成为高频泥石流。地震和强降雨耦合作用成为诱发区域灾害的根本原因,因此建议加强灾区雨季的监测预警能有效防治灾难性灾害发生。

Analysis of distribution of disasters and long term activity under earthquake and heavy rainfall

Geohazard that caused by heavy rainfall which caused catastrophic losses and become a new threat to quake-hit areas. This article through analyzed distribution characteristics of disasters and main controlling factors in Goose Foot River Basin ,at Xichang 7.5 earthquake area. Studies have shown that: (1) the disaster in basin has effect of earthquake disaster. which performance is Geohazard along the fault zone and concentrated in the East of fault, formation tendency of stratum, S shaped River caused by landslide lake, micro topographic effect and chain effects on disaster.(2) on the region have small earthquake after the 7.5 earthquake, rainfall changes smoothly. The disaster has long activity, landslides is frequent occurrence and Goose Foot River has become a high-frequency debris flow. The coupling action of earthquake and heavy rainfall is the basic cause of regional disaster, Therefore, it is suggested that the monitoring and early warning of rainy season in disaster areas ,which can effectively prevent and control the occurrence of catastrophic disasters.