地震地磁观测与研究2023，Vol.44Issue(5)：74-80,7.DOI:10.3969/j.issn.1003-3246.2023.05.010
甚宽频带地震计自噪声测试方法对比
Comparison of self-noise measurement methods for very broadband seismometers
摘要
Abstract
A collocation test for the JS-120 very broadband seismometers was conducted with the methods of two and three seismometers at the Hebei Hongshan National Observatory on Thick Sediments and Seismic Hazards.We selected 600 hours of continuous observation record samples and extracted typical self-noise values with advantage probability based on the sub-band probability statistics method to analyze differences in test results.The results show that the three seismometers method can correct the transfer function difference between seismometers through the ratio of cross-power spectra,and the result is lower and more stable than the two seismometers method.When the performance of seismometers differs,seismometers with higher self-noise will affect the coherence of the records,leading to higher self-noise results for other seismometers.Due to inconsistencies in the installation process,the shape of the seismometers'self-noise power spectrum curves change in the range of 0.1 to 1 Hz close to the secondary microseism frequency band,and the performance of the two seismometers method is more obvious.In the low-frequency band below 0.04 Hz,the seismometer self-noise level is relatively high,which is close to the observation ambient noise.The influence of seismometer self-noise in the low-frequency band should be considered when the selection of observatories for scientific experiments with low noise and the evaluation of ambient noise level was conducted.关键词
甚宽频带地震计/自噪声/同址比测/分频带概率统计/优势概率典型值Key words
very broadband seismometers/self-noise/collocation test/sub-band probability statistics/typical values with advantage probability引用本文复制引用
尹康达,李冬圣,张晓刚,李小军..甚宽频带地震计自噪声测试方法对比[J].地震地磁观测与研究,2023,44(5):74-80,7.基金项目
河北省地震科技星火计划(项目编号:DZ2023120800013,DZ20190415004) （项目编号:DZ2023120800013,DZ20190415004）
