浙江临安地震台阵勘选测试与背景噪声水平分析

在大中城市周边建设地震台阵,可解决城市内地震监测台站建设不便和背景噪声高等问题,增强人口密集区的地震监测能力。杭州湾地区沉积层较厚,建设基岩地震台站不够现实,为适应长三角区域的一体化发展,增强该区地震和非天然地震的监测能力,在浙江临安建设地震台阵。使用GL-PS60一体化宽频带地震计进行测点勘选工作,利用Welch平均周期法,对9个子台进行背景噪声功率谱估计。结果发现,背景噪声功率谱相关性较好,且与全球噪声模型一致性较好。在台阵勘选过程中,于2017年4月12日和13日分别记录到临安4.2级地震及菲律宾远震事件,波形清晰,表明初选台址效果较好,符合地震台阵建设要求。

Investigation and deployment of a seismic array in Lin'an,Zhejiang Province

The construction of seismic array around big cities can solve the problems of inconvenient construction of earthquake monitoring stations in cities and high background noise, and enhance the ability of earthquake monitoring in densely populated areas. In order to adapt to the integrated development of the Yangtze River Delta region and enhance the monitoring ability of earthquakes and non-natural earthquakes in this area, a seismic array was built in Lin'an, Zhejiang Province. The GL-PS60 integrated broadband seismometer was used to carry out the site selection survey, and the Welch average-period-method was used to calculate background noise power spectral density for 9 sub-stations. The results show that the correlation of the power spectrum of background noise is good, and it is consistent with the global noise model. Lin'an M_L 4.2 earthquake and Philippine teleseismic events were recorded on April 12 and 13, 2017, respectively, with clear waveform, indicating that the preliminary site selection is good and meets the requirements of seismic array construction.