摘要
2008年5月12日14时28分,我国四川发生里氏8.0级大地震,发震构造为龙门山断裂带。形成了NE向映秀-北川断裂地表破裂带,彭县—灌县断裂破裂带以及NW向的小鱼洞破裂带,表现为逆冲-走滑性质。目前,有关地表破裂、次生地质灾害及堰塞湖等开展了大量的调查工作,而地震对河流形态的影响还缺少较为系统的分析。在野外地震地貌考察的基础上,根据河流走向与断层位置关系,并结合地表破裂特征,总结了汶川地震对现代河流形态影响的几种地貌类型:顺向陡坎跌水,河道错动,断塞湖(塘),河流改道等,并对其演化趋势进行了讨论。分析了汶川地震的河流水文效应:地震增加了河流泥沙含量,改变了河流水质,同时,也使得河流与地下水系统之间的联系更为紧密。
The Ms 8.0 Wenchuan earthquake strongly shocked at 14：28 on May 12,2008.The seismogenic structure belongs to the Longmenshan fault zone.Its surface rupture belts include those formed along the NE striking Yingxiu-Beichuan and Pengxian-Guanxian faults and the NW striking Xiaoyudong fault.The surface ruptures are characterized by thrust faulting with strike-slip movement.The surface ruptures,landslides,fall and dammed lakes were surveyed with great efforts after the Wenchuan earthquake.However,the morphological effects of Wenchuan earthquake on rivers were not analyzed or discussed.Based on our field survey on earthquake geomorphology,this paper summarizes the morphological effects of Wenchuan Earthquake on rivers including waterfalls by consistent direction fault scarps,river slipping,earthquake fault lakes/poodles and riverway changing.Their developing trends are discussed.The hydrological effects of Wenchuan Earthquake on rivers are also analyzed. The Wenchuan earthquake increased the river silt and sediment contents and changed the river water quality.Furthermore,it heightened the connections between rivers and the groundwater systems.
出处
《高校地质学报》
CAS
CSCD
北大核心
2009年第3期365-370,共6页
Geological Journal of China Universities
关键词
汶川地震
河流跌水
河道错动
断塞湖(塘)
河流改道
水文效应
Wenchuan earthquake
river waterfall
river slipping
earthquake fault lake/poodle
riverway changing
hydrological effects
