Lithospheric imaging via teleseismic scattering tomography     

A. W. Frederiksen  J. Revenaugh 《Geophysical Journal International》2004,159(3):978-990

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Relations between reflection and transmission responses of three-dimensional inhomogeneous media   总被引：1，自引：0，他引：1  

Kees Wapenaar  Jan Thorbecke  Deyan Draganov 《Geophysical Journal International》2004,156(2):179-194

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海原西断层松山附近地区微震尾波Q值——中法合作数字微震监测台(网)应用之一          下载免费PDF全文

荣代潞 《地震工程学报》1997,19(3):26-31

利用中法合作建立的微震数字地震台的资料研究了海原西断层松山附近地区的微震尾波的衰减特征．计算了１７０次地震的７个频带的尾波Ｑｃ值，得出该地区尾波衰减可用Ｑｃ＝５２ｆ１．０９表示，表明这个地区是构造活动水平较高的地区．  相似文献   

Intrinsic and scattering attenuation from observed seismic codas in the Almeria Basin (southeastern Iberian Peninsula)   总被引：2，自引：0，他引：2  

L. G. Pujades  A. Ugalde  J. A. Canas  M. Navarro  F. J. Badal  V. Corchete 《Geophysical Journal International》1997,129(2):281-291

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Generation of the teleseismic P-wave coda from Aleutian earthquakes     

Charles H. Estabrook  Michael Weber  Rainer Kind 《Geophysical Journal International》1997,130(2):349-364

We investigate large-amplitude phases arriving in the P -wave coda of broad-band seismograms from teleseisms recorded by the Gräfenberg array, the German Regional Seismic Network and the Global Seismic Network. The data set consists of all events m _b≤ 5.6 from the Aleutian arc between 1977 and 1992. Earthquakes with large-amplitude coda waves correlate with the presence of oceanic crust in the source region. The amplitudes sometimes approach those of the P wave, much larger than predicted by theory. Modelling indicates that phases in the P -wave coda cannot be P -wave multiples beneath the source and receiver, or underside reflections, which precede PP , from upper-mantle discontinuities. Among the events, seismograms are very similar, where the arrival times of the unusual phases agree approximately with the predicted times of S -to- P conversions from the upper-mantle discontinuities under the source. Because the large-amplitude phases in the P -wave coda have little, if any, dependence on event depth and have predominantly an SV -wave radiation pattern towards the receiver, we suggest that they originate as SV and/or Rayleigh waves and are enhanced by lateral heterogeneity and multipathing from the subducting Aleutian slab.  相似文献   

Attenuation characteristics of coda waves and estimation of Q c values in eastern China     

Cai-Zhong Huang  Huan-Cheng Ge  Tie-Ying Jiang 《地震学报(英文版)》1995,8(2):241-248

For short-period near-earthquake records in eastern China, from the empirical attenuation formula of coda ground motion amplitudeA with timeτ: lgA=G−2. 235 lgτ, using the single scattering theory modified with epicentral distance, we obtain the curve family of corrected coda amplitudeA _c(r,t), andω/2Q _c values for each time interval of coda. From this,Q _c(f,h) values, which correspond to each observational average frequency and sampling depth, are calculated. The results substantially agree with those observationalQ _c values in Yunnan, Beijing and central Asia.  相似文献   

Attenuation　characteristics　of　coda　waves　and　estimation　of　Qc　values　in　eastern　China     

黄才中  葛焕称  江铁鹰 《地震学报(英文版)》1995,(2)

ＡｔｔｅｎｕａｔｉｏｎｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｃｏｄａｗａｖｅｓａｎｄｅｓｔｉｍａｔｉｏｎｏｆＱｃｖａｌｕｅｓｉｎｅａｓｔｅｒｎＣｈｉｎａ黄才中，葛焕称，江铁鹰Ｃａｔ－ＺｈｏｎｇＨＵＡＮＧ；Ｈｕａｎ－ＣｈｅｎｇＧＥａｎｄＴｉｅ－ＹｉｎｇＪＩ...  相似文献   

数字地震数据尾波Q值计算实用软件     

华正兴  高龙生 《地震地磁观测与研究》1995,16(1):35-41

利用高精度的数字地震尾波记录来测定一定区域范围内或地震活动区内的介质品质因素Ｑ，是一项非常有意义的工作。本文介绍了一套方法上较完备和相对规范化的尾波Ｑ值计算软件，运用中国数字化地震台网（ＣＤＳＮ）记录给出计算实例。  相似文献   

Research on coda Q distribution in Beijing and its surrounding regions     

Yun-Sheng Ma  Tian-Zhong Zhang  Huan-Sheng Zhang 《地震学报(英文版)》1995,8(4):551-561

Based on the single scattering model of seismic coda waves, we have calculated theQ-factor in Beijing and its surrounding regions by means of calculating the power density spectrum in frequency domain with a fixed time window. The digital seismic data of 69 earthquakes from Beijing Telemetered Seismographic Network are used. These earthquakes were recorded from January 1, 1989 to December 31, 1990 at 20 stations. This paper shows the variations of the codaQ-factors in the studied region with different sites, frequency and lapse time, and the temporal change of the codaQ-factors in these two years. The results indicate that codaQ-factor depends strongly on the lapse time and frequency. It is assumed that whenQ _C=Q ₀f^η, for the three time windows of 15–30s, 30–60s and 60–90s, the average values ofQ ₀ are 48, 115 and 217; and the average values ofη are 0. 89, 0.91 and 0.74, respectively. Contribution No. 95A0009, Institute of Geophysics, SSB, China. This work is a contract subject 85-04-01-02 of the State Seismological Bureau, China.  相似文献   

Single Scattering Theory Versus Numerical Modelling In 2-D Random Media   总被引：1，自引：0，他引：1  

M. Roth  M. Korn 《Geophysical Journal International》1993,112(1):124-140

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