Attenuation due to second-order scattering in material containing cracks.   总被引：1，自引：0，他引：1  

J. A. Hudson 《Geophysical Journal International》1990,102(2):485-490

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Frequency dependence of Q in the mantle underlying the shield areas of Eurasia, Part III: The Q model   总被引：2，自引：0，他引：2  

Zoltan A. Der  Alison C. Lees  Vernon F. Cormier 《Geophysical Journal International》1986,87(3):1103-1112

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Frequency dependence of Q in the mantle underlying the shield areas of Eurasia, Part I: analyses of short and intermediate period data   总被引：1，自引：0，他引：1  

Zoltan A. Der  Alison C. Lees  Vernon F. Cormier  Lisa M. Anderson 《Geophysical Journal International》1986,87(3):1057-1084

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Interpretation of surface wave spectra in laterally inhomogeneous media     

Peter Malischewsky 《Geophysical Journal International》1989,99(2):305-306

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Spherically symmetric attenuation within the Earth from normal mode data   总被引：3，自引：0，他引：3  

Rudolf Widmer  Guy Masters  Freeman Gilbert 《Geophysical Journal International》1991,104(3):541-553

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Seismic Yield Estimation Using Teleseismic P-And Pkp-Waves Recorded At the Grf-(Gräfenberg) Array     

Jörg Schlittenhardt 《Geophysical Journal International》1988,95(1):163-179

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Equations for the Estimation of Strong Ground Motions from Shallow Crustal Earthquakes Using Data from Europe and the Middle East: Horizontal Peak Ground Acceleration and Spectral Acceleration   总被引：25，自引：13，他引：12  

N.?N.?AmbraseysEmail author  J.?Douglas  S.?K.?Sarma  P.?M.?Smit 《Bulletin of Earthquake Engineering》2005,3(1):1-53

This article presents equations for the estimation of horizontal strong ground motions caused by shallow crustal earthquakes with magnitudes M_w 5 and distance to the surface projection of the fault less than 100km. These equations were derived by weighted regression analysis, used to remove observed magnitude-dependent variance, on a set of 595 strong-motion records recorded in Europe and the Middle East. Coefficients are included to model the effect of local site effects and faulting mechanism on the observed ground motions. The equations include coefficients to model the observed magnitude-dependent decay rate. The main findings of this study are that: short-period ground motions from small and moderate magnitude earthquakes decay faster than the commonly assumed 1/r, the average effect of differing faulting mechanisms is not large and corresponds to factors between 0.8 (normal and odd) and 1.3 (thrust) with respect to strike-slip motions and that the average long-period amplification caused by soft soil deposits is about 2.6 over those on rock sites. Disappointingly the standard deviations associated with the derived equations are not significantly lower than those found in previous studies.  相似文献   

Calibration of Local Magnitude M<Subscript>L</Subscript> in the Azores Archipelago Based on Recent Digital Recordings     

Eva?GóngoraEmail author  Fernando?Carrilho  Carlos S.?Oliveira 《Pure and Applied Geophysics》2004,161(3):647-659

—The development of the digital seismic network in the Azores Archipelago during recent years made it possible to obtain the amplitudes (waveform) of recorded motion in a large set of stations. With this new data, maximum amplitudes of the Wood Anderson seismograph are computed, for each station/component, which, together with epicentral distances, allows for the estimation of local magnitude M _L . We used data recorded in 8 digital permanent three-component stations, with inter-stations distances up to 300 km, in the period June 1998 – June 2000, corresponding to a set of 1315 events with magnitude (M _L or M _D ) 2<M<5.8 and epicenters located in the Azores region, to estimate the coefficients of the equation to compute M _L , as well as to determine the corrections to be applied to each station. The new set of parameters, formed by attenuation coefficients and station corrections, were introduced in the calculations of the M _L , leading to smaller dispersions in the analyzed dataset. We also conclude that the attenuation in the first 150 km is similar to the California values, although higher for longer distances.  相似文献   

An investigation of analysis of variance as a tool for exploring regional differences in strong ground motions   总被引：2，自引：1，他引：1  

John?DouglasEmail author 《Journal of Seismology》2004,8(4):485-496

The statistical technique known as analysis of variance is applied to a large set of European strong-motion data to investigate whether strong ground motions show a regional dependence. This question is important when selecting strong-motion records for the derivation of ground motion prediction equations and also when choosing strong-motion records from one geographical region for design purposes in another. Five regions with much strong-motion data (the Caucasus region, central Italy, Friuli, Greece and south Iceland) are investigated here. For the magnitude and distance range where there are overlapping data from the five areas (2.50 M_s 5.50, 0 d 35 km) and consequently analysis of variance can be performed, there is little evidence for a regional dependence of ground motions. There is a lack of data from moderate and large magnitude earthquakes (M_s > 5.5) so analysis of variance cannot be performed there. Since there is uncertainty regarding scaling ground motions from small to large magnitudes whether ground motions from large earthquakes are significantly different in different parts of Europe is not known. Analysis of variance has the ability to complement other techniques for the assessment of regional dependence of ground motions.  相似文献   

Seismicity and seismic hazard mapping of northern Algeria: Map of Maximum Calculated Intensities (MCI)   总被引：3，自引：1，他引：2  

M.S. Boughacha  M. Ouyed  A. Ayadi  H. Benhallou 《Journal of Seismology》2004,8(1):1-10

An earthquake catalogue covering the period1716–2000, comprising 2430 events, has beencompiled for the region lying between3°W-9°E and 31°N-38°N. It results fromraw data of IGN, ISC, USGS and Algeriansources, enabling an input consisting oforigin time H, geographical coordinates(longitude and latitude) and at least one of thefollowing parameters: surface wavemagnitude Ms, body wave magnitude Mb,epicentral intensities Io. Empiricalrelations permit transformations of Mb andMs into Io. The output consists in H,, , Ms, Mb, Io, and focal depth h whichis fixed to 10 km. The number ofevents falls to 1458 characterised by Ms 3.3 and Mb 3.6, or Io III. The fixed depth is suggested by thebest documented Algerian macroseismic mapsthat also lead to an empirical intensityattenuation law. A first application ofthis catalogue allows the drawing up of anupdated Seismicity and a MaximalCalculated Intensities (MCI) Maps ofAlgeria. The MCI map is obtained by usingthe empirical attenuation law: theintensities inferred by the whole eventsconstituting the catalogue are computed atnodes of a 5×5-km grid covering the area ofstudy. The corresponding maximum value isassigned to each node. The MCI map producedthat way gives precise spatial informationin comparison with Maximum ObservedIntensities (MOI) maps obtained in previousmacroseismic studies. This document may beuseful in mapping the seismic hazard inNorthern Algeria, without attachingprobabilities to ground-motionparameters.  相似文献