地震研究

以2016年5月18日云南云龙MS5.0地震为例,选取距震中较近的3个台站和较远的5个台站记录的2016年1—9月的气枪震源信号,使用互相关检测技术得到地震前后这8个台站各自稳定震相走时变化特征。结果表明:云龙地震前,各台均存在不同程度的走时异常变化。离震中较近的3台站中,震中西侧和东侧台站走时变化有一定差别,但都在地震前的3、4月变化较大; 而离地震较远的5个台站则变化趋势特征一致,幅度略有差别; 离地震较近台站走时变化幅度明显大于离地震较远台站; 地震前小于0.7 m的水位变化并未对各台走时变化产生实质性影响。同时对比了云龙台FSQ水管倾斜的形变观测数据,监测到同一时段地下应力发生变化。

Taken the Yunnan Yunlong MS5.0 earthquake as an example,we chose the airgun signal data recorded by three seismic stations near the epicenter of the Yunlong earthquake and five seismic stations which is a bit further from the epicenterbetween January and September 2016.We studied travel time variety characteristics of the eight seismic stations by using cross-correlation time delay measurement technology.The results show that the travel time of every station had abnormal variation before the earthquake.For the three near stations,the travel time from the eastern and western of the earthquake was different,but they all had larger changes in March and April.For the five further stations,the trend characteristics were consistent,but the range was different.The change of the travel time from the near seismic stations is more lager than the far seismic stations.Before the earthquake,less than 0.7 m of water level change can't make a substantial change on travel time.Compared with the crustal deformation observation data of the FSQ water pipe tilt in Yunlong seismic station,we observed stress changes occurred in the same period of time.

引言
1 云南宾川气枪发射台及观测情况
2 数据处理方法
3 云龙M_S5.0地震前后走时变化特征及影响因素分析
4 云龙台形变资料分析
5 讨论与结论

图1 2013—2014年(a)、2015—2016(b)宾川主动源激发日频次图<br/>Fig.1 Transmitting daily frequency of airgun of Binchuan acitve seismic station from 2013 to 2014(a),and 2015 to 2016(b)

图1 2013—2014年(a)、2015—2016(b)宾川主动源激发日频次图
Fig.1 Transmitting daily frequency of airgun of Binchuan acitve seismic station from 2013 to 2014(a),and 2015 to 2016(b)

图2 数据处理流程图<br/>Fig.2 Flow chart of data processingp

图2 数据处理流程图
Fig.2 Flow chart of data processingp

图3 云龙地震及本文所使用台站分布情况<br/>Fig.3 Sketch diagram of station distribution used in this paper and the Yunlongearthquake

图3 云龙地震及本文所使用台站分布情况
Fig.3 Sketch diagram of station distribution used in this paper and the Yunlongearthquake

图4 2016年1—9月云龙台(YuL)、EY16台和洱源台(ErY)走时变化曲线及同一时段内水位图<br/>Fig.4 Travel time variation curves of YuL,EY16 and ErY stations and the water level from Jan.to Sep,2016

图4 2016年1—9月云龙台(YuL)、EY16台和洱源台(ErY)走时变化曲线及同一时段内水位图
Fig.4 Travel time variation curves of YuL,EY16 and ErY stations and the water level from Jan.to Sep,2016

图5 2016年1—9月53254台、53258台、53272台、53266台和53268台走时变化及同一时段内水位曲线<br/>Fig.5 Travel time variation curves of 53254,53258,53272,53266 and 532568 stations and the water level from Jan.to Sep,2016

图5 2016年1—9月53254台、53258台、53272台、53266台和53268台走时变化及同一时段内水位曲线
Fig.5 Travel time variation curves of 53254,53258,53272,53266 and 532568 stations and the water level from Jan.to Sep,2016

图6 洱源台主动源激发波形单天事件叠加(a)和模板(b)及相关性(c)分析图<br/>Fig.6 Stacked excitation waveform of every day in Eryuan station(a),template(b)and correlation analysis diagram(c)

图6 洱源台主动源激发波形单天事件叠加(a)和模板(b)及相关性(c)分析图
Fig.6 Stacked excitation waveform of every day in Eryuan station(a),template(b)and correlation analysis diagram(c)

图7 云龙台南北分量(a)、东西分量(b)水管倾斜日均值观测图<br/>Fig.7 The curves of daily average value of the water pipe tilt in NS(a)and EW(b)recorded by the Yunlong seismic station

图7 云龙台南北分量(a)、东西分量(b)水管倾斜日均值观测图
Fig.7 The curves of daily average value of the water pipe tilt in NS(a)and EW(b)recorded by the Yunlong seismic station

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引言

1 云南宾川气枪发射台及观测情况

2 数据处理方法

3 云龙M_S5.0地震前后走时变化特征及影响因素分析

4 云龙台形变资料分析

5 讨论与结论

期刊信息

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