川滇地区钻孔四分量应变仪记录的同震应变阶分析

Analysis of Coseismic Strain Step Observed by 4-Component Borehole Strain Meters in Sichuan-Yunnan Region

通过对比川滇地区6个钻孔四分量应变台站记录的汶川MS8.0级地震和芦山MS7.0级地震的同震应变阶,发现结果不满足四分量应变的自检特性,而且两组面应变的同震应变阶的张压性变化不一致,这可能和地震震级有关,也有可能和仪器的自身特性、台站所处断层环境、台站与震中的距离、元件的方位角等有关。另外,利用钻孔分量应变仪记录的同震应变阶进行相关研究时,还需对数据的可靠性做深入分析,否则可能会产生错误结果。

Through the comparative analysis of coseismic strain steps between Wenchuan Ms8.0 and Lushan Ms7.0 observed by six 4-component borehole strain meters in Sichuan-Yunnan region, we find that the observed results fail to pass self-checking, in which the tension pressure changes of two groups of plane strain coseismic strain steps are inconsistent. Such phenomenon may be related to the magnitude, the performance of the instrument, station fault environment, epicenter distance. In addition, the seismic research related to the coseismic strain steps, still need to do in-depth analysis of reliability data in order to reduce the error.