基于分量钻孔应变资料分析测区构造应变变

根据“双衬套”理论模型和应变理论, 以易县台分量钻孔应变观测资料为例解算测区构造应变变化。 由于易县台分量钻孔应变元件灵敏度不一致, 首先进行相对实地标定, 数据信度由0.7557升高到0.9344; 其次, 应用理论固体潮对易县台分量钻孔应变进行绝对标定, 得到耦合系数; 最后, 通过应变换算得到易县台观测点附近的应变参数, 面应变ε_a每年以2440 ns的速度变化, 最大剪应变ε_s以每年230 ns的速度变化, 应变主方向为138°。 综合结果表明, 易县台测区附近的构造应变呈稳定拉伸的状态。

Analysis on Changes of the Tectonic Strain in Survey Area Based on Multi-Component Borehole Straingauge

According to the “Double Bushing” theoretical model and strain theory, the tectonic strain is calculated based on the observation data from the borehole straingaugeat Yixian Station. First, considering the inconsistent sensitivity of the components of borehole strain gauge, relative field calibration is applied to the data. The results show that the reliability increased from 0.7557 to 0.9344. Second, the theoretical solid tide method is used for absolute calibration of borehole strain to obtain the coupling coefficient. At last, the strain parameters of Yixian station observation point are obtained by strain conversion.The results show that the rates of the dilation strain ε_a and maximum shear strain ε_s are 2440 ns/a and 230 ns/a respectively. The main direction of strain is 138°. According to the above mentioned results, the tectonic strain near the Yixian Station is in a stable state of expansion.