汤坑井水位观测系统体应变响应分析

ANALYSIS OF CRUSTAL BODY STRAIN RESPONSE OF TANGKENG WELL WATER LEVEL OBSERVATIONAL SYSTEM

井水位观测系统作为一种天然的体应变计,我们可以把固体潮理论值作为观测井的输入值,以维尼迪可夫调和分析结果的半日波M2波群的振幅比作为井水位观测系统的灵敏度,其倒数即为观测格值,然后就可将井水位观测转换成体应变值。本文以汤坑井为例,计算分析了由印尼远震、汶川地震、台湾地震共三种地震类型对汤坑井水位所激励的水震波,结果显示,所记录到的水震波是叠加在体应变固体潮背景上的一种阶跃,对三种地震类型都分别做出了不同程度的响应,体应变固体潮响应幅度最高可达10-7,体应变响应幅度与地震能量成正比,响应延迟时间与震中距成正比。

Because the well water level observational system can be regarded as one kind strain gauge, we can choose observing well, and then through theoretical value of solid tide as exciting value （input the Venidikov harmonic analysis of observed well water of natural body value） of the level datum we can liken the amplitude ratio of M2 wave group in half day waves to the sensitivity of well water level observational system whose reciprocal value is just the observational scale unit, so as to convert the water level value into body strain value. Then we applied it to the case in Tangkeng well, we calculate and analyze the water shock wave responded by three kinds of quakes such as Indonesian distant shock, Wenchuan earthquake and Taiwan earthquake. It shows that the water shock wave record a oscillating attenuation change overlying the background of volumetric strain solid tide, which differently responses to three kinds of quakes. The volumetric strain response can reach to 10^-7. The response amplitude keeps in direct proportion to quake energy and the delay time keeps in direct proportion to epicentral distance.