溧阳地震台地面与井下地震观测对比分析  

Comparative analysis of surface ground and underground seismic observation at Liyang seismic station

作　　者：宫杰[1] 居海华[1,2] 胡米东 张扬 张敏[1] 郝冉 陈健 GONG Jie;JU Haihua;HU Midong;ZHANG Yang;ZHANG Min;HAO Ran;CHEN Jian(Jiangsu Earthquake Agency,Nanjing 210014,Jiangsu,China;Xuzhou Seismic Station,Xuzhou 221008,Jiangsu,China;Liyang Seismic Station,Liyang 213300,Jiangsu,China)

机构地区：[1]江苏省地震局,江苏南京210014 [2]江苏省徐州地震台,江苏徐州221008 [3]江苏省溧阳地震台,江苏溧阳213300

出　　处：《地震工程学报》2022年第4期913-919,共7页China Earthquake Engineering Journal

基　　金：江苏省地震局青年科学基金项目(201902);地震科技星火计划(XH21011);徐州市重点研发计划(社会发展)项目(KC20185)。

摘　　要：为系统总结地面与井下地震观测特性,对溧阳地震台地面GL-S60与井下GL-S60B宽频带地震数据对比分析,结果显示:(1)井下地震计方位角约为176.5°,即东南、西北大致反向,并结合地震P波到时极性分析得以验证。(2)垂直向相关系数优于水平向,受人类活动干扰白天低于夜晚。(3)受台站附近南北向公路影响,地面台基噪声水平向大于垂直向,南北向最大,而井下地震计台基噪声整体较小,且水平向小于垂直向,说明深井观测能有效降低台基噪声,尤其水平向。(4)井下记录的地震信噪比次于地面,地面土层对地震波具有一定放大作用。因此,深井观测虽有效降低噪声水平,但不一定意味着高信噪比数据产出,需结合实际观测资料综合分析。To systematically summarize the characteristics of surface ground and underground seismic observation,the ground GL-S60 and underground GL-S60B broadband seismometers in the same site of Liyang seismic station were comparatively analyzed in this paper.The results show:(1)The azimuth angle of underground seismometer is about 176.5°:the southeast and northwest directions are roughly reversed.(2)The vertical correlation coefficient is better than horizontal correlation coefficient.Due to disturbance of human activities,correlation coefficient in daytime is lower than that at night.(3)Due to the disturbance of NS-direction highway near the station,the ground base noise in the horizontal direction is higher than that in the vertical direction,and that in the NS direction is the largest.The base noise of underground seismometer is small as a whole,and the noise in the horizontal direction is less than that in the vertical direction,indicating that deep-well observation can effectively reduce the base noise,especially in the horizontal direction.(4)The signal-to-noise ratio recorded by the underground seismometer is inferior to that recorded by the ground seismometer,for the observation on the ground has a certain amplification effect on the seismic wave.Underground observation can effectively reduce the noise level,but it does not mean the output of high signal-to-noise ratio data,which needs to be comprehensively analyzed in combination with the actual observation data.

关 键 词：对比分析 方位角 相关系数 台基噪声 信噪比 

分 类 号：P319[天文地球—固体地球物理学]