摘要
根据过去几十年国内外的科研成果,基于全国地下流体前兆台网数据库的统计,本文整理了中国大陆井水位观测网中对芦山Ms7.0级地震水位同震响应的台站信息,分析震中距与水位同震最大振幅的相关性,探讨水位同震阶变台站的分布与构造应力场的关系,认识芦山地震对区域应力场可能存在的影响。得到如下结论:①震中距是水位阶降和500 km范围内水位阶升的主要影响因素;②大陆范围内,水位震荡和水位阶升的影响因素,除震级、震中距外,还取决于井区水文地质条件、构造部位和井孔的特性;③在芦山Ms7.0级地震震中距500 km范围附近,水位同震阶升占据主体,区域压应力相对集中。但是在地震发生的10个月内,水位同震阶变集中区域未发生显著地震,此区域因为压应力相对集中而引发较强地震的可能性不大。
According to the researching results over the past decades and the national underground fluid precursory network database,in this paper we collect and study the co-seismic response of water level data observed in mainland of China caused by the Ms7.0 Lushan Earthquake.We analyze the correlation between the maximum water level change amplitudes and the epicentral distances and discuss the relationship between the distribution of co-seismic response wells and tectonic stress field.We recognize that the M7.0 Lushan Earthquake make the regional stress field re-distributed.We conclude that： ①The epicentral distance is the key factor to affect the step increasing and decreasing of water level within the range of 500 kilometer.②In the continental regions the factors influencing the water level variations are mainly seismic magnitudes,epicentral distance,hydrological and geological conditions,geological structure and well response characters.③Within the range of 500 km epicentral distance,the most of the co-seismic step increasing variation was caused by the M7.0 Lushan Earthquake and the regional compressive stress was relatively concentrated.But during the period of 10 months after the M7.0 Lushan Earthquake,there were no any earthquakes with magnitudes of more than Ms4.0 occurred in this area.It is impossible that the relative centralized compressive stress causes strong earthquake.
出处
《四川地震》
2014年第2期20-25,共6页
Earthquake Research in Sichuan
基金
中国地震局震情跟踪定向工作任务(2014020308)
中国地震台网中心青年科技基金(QNJJPZ-YBB-1308)
关键词
芦山地震
水位同震
地下水位
同震效应
M7.0 Lushan Earthquake
co-seismic water level
underground water level
co-seismic response
