地震研究

利用云南数字地震台网资料,计算了2008年1月1日至2018年8月13日,2018年云南通海MS5.0地震震中100 km范围内3.0≤ML<5.0地震的震源参数,得到参数间的定标律关系。为了扣除震级对视应力的影响,采用规准化视应力,获得了规准化视应力时间进程及空间分布图像。结果显示:地震视应力与震级、地震矩的皮尔逊相关系数分别为0.63,0.37,视应力与地震矩的相关性不显著; 视应力标度率特征符合区域构造特征。通海MS5.0地震前15.6个月,视应力和规准化视应力均出现高值异常,距离震中46 km,出现高值异常区域,说明该区域高视应力值对5级以上地震具有一定指示意义。

Based on data of the Yunnan Digital Seismic Network,we calculated the focal parameters of 3.0≤ML<5.0 earthquakes within a 100 km radius of the epicenter from Jan.1,2008 to Aug.13,2018,and obtained several scaling law among the parameters.In order to deduct the effect of magnitude on apparent stress,we obtain the image of temporal process and spatial distribution by using the normalized apparent stress.The results show that the Pearson correlation coefficients between apparent stress and magnitude and seismic moment are 0.63 and 0.37,respectively,which may indicate that the correlation between apparent stress and seismic moment is not significant,and the characteristics of apparent stress scale rate conform to regional tectonic characteristics.During the 15.6 months before the Tonghai MS5.0 earthquake on Aug.13,2018,both of the apparent stress and normalized apparent stress appeared high value anomalies.The high value anomaly area appeared 46 km away from the epicenter,which indicated that the high apparent stress value in this area showed certain indication significance for the occurrence of M≥5.0 earthquakes.

引言
1 研究区构造背景
2 资料选取与计算方法
3 结果分析
4 结论与讨论

图1 2008年1月1日—2018年8月13日滇南地区3.0≤ML≤5.0震中分布及构造图<br/>Fig.1 Distribution of 3.0≤ML≤5.0 earthquakes from Jan.1,2008 to Aug.13,2018 and active tectonics in the southern Yunnan

图1 2008年1月1日—2018年8月13日滇南地区3.0≤ML≤5.0震中分布及构造图
Fig.1 Distribution of 3.0≤ML≤5.0 earthquakes from Jan.1,2008 to Aug.13,2018 and active tectonics in the southern Yunnan

图2 视应力(a)、辐射能量(b)和地震矩(c)与震级之间的定标关系<br/>Fig.2 The scaling law between apparent stress(a),earthquake energy(b),seismic moment(c) and magnitude

图2 视应力(a)、辐射能量(b)和地震矩(c)与震级之间的定标关系
Fig.2 The scaling law between apparent stress(a),earthquake energy(b),seismic moment(c) and magnitude

图3 视应力(a)和拐角频率(b)与地震矩之间的关系<br/>Fig.3 Relationship between apparent stress(a)and corner frequence(b)and seismic moment

图3 视应力(a)和拐角频率(b)与地震矩之间的关系
Fig.3 Relationship between apparent stress(a)and corner frequence(b)and seismic moment

图4 2008年1月1日—2018年8月13日研究区3.0≤ML<5.0地震视应力(a)、规准化视应力(b)滑动平均时间进程图以及M-T图(c)<br/>Fig.4 The Temporal process based on apparent stress(a),normalized apparent stress(b)values moving average from 3.0≤ML<5.0 earthquakes in the research area and the M-T diagram(c)

图4 2008年1月1日—2018年8月13日研究区3.0≤ML<5.0地震视应力(a)、规准化视应力(b)滑动平均时间进程图以及M-T图(c)
Fig.4 The Temporal process based on apparent stress(a),normalized apparent stress(b)values moving average from 3.0≤ML<5.0 earthquakes in the research area and the M-T diagram(c)

表1 2008年1月1日—2018年8月13日研究区4.0≤ML<5.0地震震中100 km范围内地震视应力统计表<br/>Tab.1 Apparent stress statistics of 4.0≤ML<5.0 earthquakes in the research area from Jan.1,2008 to Aug.13,2018

表1 2008年1月1日—2018年8月13日研究区4.0≤ML<5.0地震震中100 km范围内地震视应力统计表
Tab.1 Apparent stress statistics of 4.0≤ML<5.0 earthquakes in the research area from Jan.1,2008 to Aug.13,2018

图5 2018通海地震前规准化视应力空间分布<br/>Fig.5 The spatial distribution of the normalized apparent stress before the Tonghai MS5.0 earthquake in 2018

图5 2018通海地震前规准化视应力空间分布
Fig.5 The spatial distribution of the normalized apparent stress before the Tonghai MS5.0 earthquake in 2018

陈学忠,李艳娥.2007.2006年7月4日河北文安MS5.1地震前震中周围地区小震视应力随时间的变化[J].中国地震,23(4):327-336.
陈学忠,王小平,王林瑛,等.2003.地震视应力用于震后趋势快速判定的可能性[J].国际地震动态,(7):1-4.
李艳娥,陈学忠,付虹.2012.2007年云南宁洱MS6.4地震前滇西南地区震源参数时空变化特征[J].地震,32(1):28-39.
刘红桂,缪发军,吴晶.2004.场地响应、震源参数与介质衰减的同时反演[J].地震,24(4):27-36.
刘红桂,王培玲,杨彩霞,等.2007.地震视应力在地震预测中的应用[J].地震学报,29(4):437-445.
刘祖荫,皇甫岗,金志林.1999.一九七〇年通海地震[M].北京:地震出版社,1-257.
乔慧珍,程万正,陈学忠.2006.安宁河—则木河断裂带地震视应力研究[J].地震研究,29(2):125-130.
王琼,陈学忠,王琳瑛.2005.岫岩地震序列视应力变化及其预测意义[J].地震,25(2):91-97.
闻学泽,杜方,龙峰,等.2011.小江和曲江-石屏断裂系统的构造动力学与强震序列的关联性[J].中国科学:地球科学,41(5):713-724.
吴忠良,黄静,林碧苍.2002.中国西部地震视应力的空间分布[J].地震学报,24(3):293-301.
吴忠良.2001.由宽频带辐射能量目录和地震矩目录给出的视应力及其地震学意义[J].中国地震,17(1):8-15.
杨志高,张晓东.2010.紫坪铺水库地区蓄水前后视应力标度率变化研究[J].地球物理学报,53(12):2861-2868.
易桂喜,闻学泽,辛华,等.2011.2008年汶川MS8.0地震前龙门山—岷山构造带的地震活动性参数与地震视应力分布[J].地球物理学报,54(6):1490-1500.
张培震,邓起东,张国民,等.2003.中国大陆的强震活动与活动地块[J].中国科学:地球科学,33(增刊1):12-20.
赵翠萍,陈章立,华卫,等.2011.中国大陆主要地震活动区中小地震震源参数研究[J].地球物理学报,54(6):1478-1489.
Abercrombie R E.1995.Earthquake source scaling relationships from-1 to 5 ML Using seismograms recorded at 2.5 km depth[J].J Geophys Res,100(B12):24-24.
Aki K.1967.Scaling law of seismic spectrum[J].J Geophys Res,72(4):1217-1231.
Atklnson G M.1992.The shape of ground motion attenuation curves in southeastern Canada[J].Bulletin of the Seismological Society of America,82(5):2014-2031.
Brune J N.1970.Tectonic stress and the spectra of seismic waves from earthquakes[J]. J Geophys Res,75(26):4997-5009.
Choy G L,Boatwright J L.1995.Global patterns of radiated seismic energy and apparent stress[J].J Geophys Res,100(B9):18205-18228.
Izutani Y,Kanamori H.2001.Scale-dependence of seismic energy-to-moment ratio for stike-slip earthquakes in Japan[J].Geophys Res Lett,28(20):4007-4010.
Mayeda K,Gök R,Walter W R,et al.2005.Evidence for non-constant energy/moment sacling from coda-derived source spectra[J].Geophys Res Lett,32(10):153-174.
Mayeda K,Walter W R.1996.Moment,energy,stress drop,and source spectra of western United State earthquakes from regional coda envelopes[J].J Geophys Res,101(B5):11195-11208.
Mouslopoulou V,Nicol A,Little T A,et al.2007.Displacement transfer between intersecting regional strike-slip and extensional fault systems[J].Journal of Structural Geology,29(1):100-116.
Takahashi T.2005.Scale dependence of apparent stress for earthquakes along the subducting pacific plate in the northeastern Honshu,Japan[J].Bull Seism Soc Am,95(4):1334-1345.
Tapponnier P,Peltzer G,Le Dain A Y,et al.1982.Propagating extrusion tectonics in Asia:New insights from simple experiments with plasticine[J].Geology,10(10):611.
Wang E.1998.Late cenozoic Xianshuihe/Xiaojiang and Red River fault systems of southwestern Sichuan and central Yunnan,China[J].Special Paper of the Geological Society of America,327:1-108.
Wu Z L.2001.Scaling of apparent stress from broadband radiated energy catalogue and seismic moment catalogue and its focal mechanism dependence[J].Earth Planets Space,53(10):943-948.
Wyss M,Brune J N.1968.Seismic moment,stress,and source dimensions for earthquakes in the California-Nevada region[J].Journal of Geophysical Research,73(14):4681-4694.

备注

引言

1 研究区构造背景

2 资料选取与计算方法

3 结果分析

4 结论与讨论

期刊信息