华南地震

认识台站场地响应对提高台网产出数据的准确性具有重要的意义。分析了广东台网72个测震台站的地脉动记录数据,利用谱比法计算得到各台站0.1~20Hz的场地响应。结果表明有32个台站场地响应曲线平缓,无明显频率放大点;有32个台站的场地响应曲线在部分频率范围表现出较高值;还有4个台站场地响应曲线表现轻微场地缩小作用和4个台站场地响应曲线呈起伏剧烈的形态。综合台基岩性分析,发现台站的基岩硬度越大、结构越致密,场地放大作用越小。进一步利用2011年1月至2019年10月广东台网记录到的852次地震事件（ML≥2）,分析了台站场地响应对单台震级的影响,结果发现大部分台站的震级偏差结果与场地响应具有一定关系,考虑场地响应的单台震级校正值能够在一定程度上减小单台震级偏差,提高单台震级的准确性。

Researching the site response of the stations is of great significance to improve the accuracy of the output data of the seismic network. The paper processed the microtremors noise data recorded by 72 stations of Guangdong Seismic Network,and calculated the site response of each station at 0.1-20 Hz based on horizontal-to-vertical(H/V) spectral ratio method. The results show that the site response curves of 32 stations are flat,and there were no obvious frequency amplification points. The site response curves of 32 stations showed higher values in some frequency ranges. In addition,there were 4 stations showing slight site reduction and 4 stations with sharply fluctuating response curves. Based on comprehensive lithology analysis of the platform,it is found that the greater the hardness of the bedrock and the denser the structure,the smaller the site amplification effect. This paper further uses the 852 earthquake events with ML ≥2 recorded by the Guangdong Station Network from January 2011 to October 2019 to analyze the effect of the station site response on the magnitude of a single station. As a result, the magnitude deviation of most stations has a certain relationship with the site response. The single magnitude correction value obtained from the site response can reduce the deviation between the single magnitude and the average magnitude of the network to a certain extent and improve the accuracy of the single station magnitude

引言
1 方法
2 噪声数据与处理
3 场地响应与分析
4 场地响应对M_L震级的校正
5 结语

图1 广东地区测震台站及本文所用地震分布图<br/>Fig.1 Distribution of seismic stations in Guangdong and earthquakes used in this paper

图1 广东地区测震台站及本文所用地震分布图
Fig.1 Distribution of seismic stations in Guangdong and earthquakes used in this paper

图2 观测数据时长和时段的参数对比<br/>Fig.2 Parameter comparison of time length and time period of observation data

图2 观测数据时长和时段的参数对比
Fig.2 Parameter comparison of time length and time period of observation data

图3 无明显放大的台站场地响应<br/>Fig.3 Site response of stations without obvious amplification

图3 无明显放大的台站场地响应
Fig.3 Site response of stations without obvious amplification

图4 有较明显放大的台站场地响应<br/>Fig.4 Site response of stations with more obvious amplification

图4 有较明显放大的台站场地响应
Fig.4 Site response of stations with more obvious amplification

图5 有轻微缩小的台站场地响应（a）和场地响应曲线起伏大的台站（b)

图6 各类型基岩的台站场地响应<br/>Fig.6 Site response of stations on various types of bedrock.

图6 各类型基岩的台站场地响应
Fig.6 Site response of stations on various types of bedrock.

图7 本文结果与黄玉龙等得到的场地响应结果对比<br/>Fig.7 Comparison of results between this paper and Huang. et al.

图7 本文结果与黄玉龙等得到的场地响应结果对比
Fig.7 Comparison of results between this paper and Huang. et al.

图8 量规函数对震级的影响<br/>Fig.8 The influence of the calibration function on the magnitude

图8 量规函数对震级的影响
Fig.8 The influence of the calibration function on the magnitude

图9 HEJ台站和HEP台站的场地响应和单台震级残差统计<br/>Fig.9 Statistics of site response and single magnitude residuals of HEP Station and HEJ Station

图9 HEJ台站和HEP台站的场地响应和单台震级残差统计
Fig.9 Statistics of site response and single magnitude residuals of HEP Station and HEJ Station

表1 广东台网48个台站校正前后的平均震级残差统计<br/>Table 1 Statistics of average magnitude deviation of 48 stations in Guangdong Seismic Network before and after correction

表1 广东台网48个台站校正前后的平均震级残差统计
Table 1 Statistics of average magnitude deviation of 48 stations in Guangdong Seismic Network before and after correction

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备注

引言

1 方法

2 噪声数据与处理

3 场地响应与分析

4 场地响应对M_L震级的校正

5 结语

期刊信息

备注