张渤带洞体应变参数解算及结果分析

Calculation and research of the strain parameters by cave strain observation of the Zhangjiakou-Bohai seismic belt

摘要:

采用张渤带2002年以来的洞体应变观测资料,首先利用Venedikov调和分析方法计算带内各个台站洞体应变测项的潮汐因子和相位滞后,并以潮汐因子的稳定性对观测资料进行了质量评价。其后,以怀来台伸缩仪为例讨论了3分量和2分量观测解算平面应变参数的模型及其适用性,结果表明二者的相关系数在0.9以上。在此基础上,选取张渤带上资料较稳定的16个洞体应变台站资料进行了应变参数时间序列计算,并对华北M5.0地震前应变参数同步变化现象进行了总结。最后对比了洞体应变与GPS应变的差异,并分析了可能的原因。

Abstract:

The paper calculates the tide factor and phase lag by using Venedikov harmonic analysis of Cave Strain Observation of the Zhangjiakou-Bohai seismic belt, and the stability of the tide factor as the evaluation index. The paper then discusses the calculation models and usability of three orientation and two orientation strain parameters based on Huailai station, and the conclusion shows that the correlation coefficient of two calculation models results is above 0.9. We calculate the strain parameters time sequence of 16 stations on the Zhangjiakou-Bohai seismic belt with the calculation model of strain parameters, and we summarize the significant trend reverse of the strain parameters on the several earthquakes （ML ≥ 5.0） of North China. Finally we contrast the cave strain and GPS strain, and discuss the possible reasons of the difference.