[关键词]
[摘要]
为解决EDAS-24GN6数据采集器对策克台井下宽频带地震计GL-S120B进行正弦标定的过程中产生的响应波形限幅问题,分析了数据采集器-地震计这一系统的标定过程及原理,结合GL-S120B的幅频响应特征,推导出正弦标定频点参数中的频率f、衰减因子λ与标定响应波形限幅之间的关系。分析表明,在GL-S120B平坦响应频带内,为避免出现标定波形响应限幅,频率f与衰减因子λ的乘积应至少大于限幅下限50.93;而在其衰减响应频带内,由于地震计电压灵敏度的衰减,频率f与衰减因子λ的乘积最小取值也相应减小。据此,对衰减因子λ进行校正,并再次对GL-S120B进行正弦标定。标定及计算结果显示:标定波形未限幅,GL-S120B三分向幅频响应特征较为一致;灵敏度对出厂值的变化率保持在5%范围内。本研究结论可为采用EDAS-24GN6和GL-S120B地震观测系统的台站进行正弦波标定提供频点参数,并为其他台站解决正弦标定波形限幅问题提供分析依据。
[Key word]
[Abstract]
In this paper, the relationship between frequency f, decay factor λ and clipping of response waveform has been derived by analyzing the calibration process, principle of the Data Collector-Seismometer system and amplitude-frequency response characteristics, to solve the clipping problem of response waveform when conducting a sine calibration on Data Collector EDAS-24GN6 and Borehole Broadband Seismometer GL-S120B system. The results show that in order to avoid the clipping problem of response waveform, the product of frequency f and decay factor λ should be at least greater than the lower limit of 50.93 in the flat response frequency band of GL-S120B. However, in the decay response frequency band, the minimum value of the product is also reduced accordingly for the decay of voltage sensitivity. After the correction of decay factor, sine calibration of GL-S120B is conducted for the second time accordingly. The calculation results of calibration show that no clipping of the response waveform occurred and the amplitude-frequency response characteristics of its three-component are relatively consistent, with the change rate of voltage sensitivity to factory value within 5%. The conclusions of this study can provide frequency points parameters for sine calibration of stations using EDAS-24GN6 and GL-S120B seismic systems, and provide analytical basis for solving the clipping problem of sine calibration response waveform.
[中图分类号]
P315
[基金项目]
冯雪东,男,1992年生,助理工程师,主要从事地震监测工作。E-mail:937896898@qq.com