sPL震相在江苏高邮M 4.9级地震震源深度测定中的应用  

The application of the sPL phase in Gaoyou M 4.9 Earthquake in determination of focal depth

作　　者：詹小艳[1] 朱升初[1] 王恒知[1] 薛莹莹[1] 王俊[1] 

机构地区：[1]江苏省地震局,南京210014

出　　处：《地球物理学进展》2014年第4期1609-1614,共6页Progress in Geophysics

基　　金：江苏省地震局青年基金(13401)资助

摘　　要：2012年7月20日20时11分在江苏高邮与宝应交界发生了M4.9级地震,是江苏地区陆地上近22年来的最大地震.本文是运用频率-波速（F-K）方法,来模拟得到深度震相sPL在不同深度模型下的理论地震图,然后在径向（R）、切向（T）和垂直向（Z）上与实际观测波形进行拟合比较,来最终确定出震源深度.根据sPL震相的优势震中距范围30~50 km,从江苏省数字地震台网中,筛选出波形记录质量信噪比高的宝应台（BY）、盐城台（YC）来进行计算,计算结果显示：宝应台和盐城台在震源深度模型分别为11 km和10 km时,理论地震图和实际观测波形的拟合结果最为接近.这一结果与利用结合波形互相关的双差定位法获得的震源深度,约10.2 km基本一致,初步表明在覆盖层厚的江苏中部地区,利用sPL震相来测定震源深度是可靠的.Gaoyou and Baoying M 4.9 earthquake occurred at20：11 on July 20,2012,It is the biggest earthquake of nearly 22 years on land in Jiangsu area.This article use the F-K method to simulate sPL depth phases obtained synthetic seismogram at different depths model,then fitted compare with the actually observed waveform in the radial direction（R）、tangential（T）and vertical direction（Z）,the focal depth is finally determined.According to the range of advantage epicentral distance of sPL phases is 30~50 km,to filter out Baoying（BY）、Yancheng station（YC）of waveform recorded high SNR to calculate From Jiangsu digital seismic network,the calculated result shows：the fitting results of synthetic seismogram and observed waveform at Baoying and Yancheng station was the closest when focal depth model were 11 km and10 km.This result was Consistent with focal depth about 10.2 km,to be obtained from the double difference method that be used of combined with cross-correlation waveform,Preliminary indication of using sPL phase to determine the focal depth is reliable in the central region of Jiangsu of covering thickness.

关 键 词：震源深度 sPL震相 F-K方法 理论地震图 

分 类 号：P315[天文地球—地震学]