用地震仪准确标定钻孔应变仪

Accurate Calibration of Borehole Strainmeter with Seismometer

通过共同观测远震面波,可以用地震仪标定钻孔应变仪。其基本思路是先用勒夫波标定剪应变灵敏系数B值,再用瑞利波标定面应变灵敏系数A值。但用不同远震的面波标定出的B值和A值差别较大。为此,引入效度来表示所用地震的面波能够准确地标定出B值和A值的程度,用效度最高的标定值作为最终标定值。用该方法标定仁和地震台的钻孔应变仪,得到A=0.36,效度为-0.71;B=0.73,效度为-0.92。

The borehole strainmeter can be calibrated by seismometer through joint observation of teleseismic surface waves.The basic idea is to calibrate the shear strain sensitivity coefficient B with Love waveform first and then calibrate the surface strain sensitivity coefficient A with Rayleigh waveform.However,we find that the B and A calibrations of different teleseismic surface waves are quite different.Therefore,validity is introduced to indicate the degree to which the surface waves can be accurately calibrated to B and A values,and the calibration with the highest validity is used as the final calibration result.This method is applied to calibrate the borehole strainmeter of Renhe seismic station,and the results are as follows:A=0.36,with a validity of-0.71;B=0.73,with a validity of-0.92.