Modeling of long-period body waves of the Ms = 7.3 Borah Peak, Idaho, earthquake suggests that the earthquake was a simple rupture that nucleated at a depth of about 16 km and propagated unilaterally northwestward toward the surface. The seismic moment tensor obtained from the inversion of teleseismic body wave amplitude data agrees well with the fault plane solution obtained from short-period ...

The seismic moment and source orientation of the 8 November 1980 Eureka, California, earthquake (Ms = 7.2) are determined using long-period surface and body wave data obtained from the SRO, ASRO, and IDA networks. The favorable azimuthal distr ibution of the recording stations allows a well-constrained mechanism to be determined by a simultaneous moment tensor inversion of the Love and Rayleigh...

Seismic moment tensor and finite-source analyses are performed for the 21 February 2008 Wells, Nevada earthquake. Using complete, intermediate period (10-50s), regional waveforms, and assuming the U. S. Geological Survey (USGS)-reported hypocenter, the best-fit moment tensor solution is a normal mechanism that strikes approximately northeast-southwest, consistent with the trend of Basin and Ran...

The accuracy of teleseismic estimates of moment, fault area, dislocation and stress drop was tested for the case of a thrust fault: the San Fernando, California, earthquake of Feburary 9, 1971. On the basis of P-wave spectra of 25 stations and S-wave spectra of 9 stations, the respective values were found to be 0.7.1026 dyne-cm, 570 km 2, 45 cm, and 14 bars. They agree well with the same parame...

in this study, analysis is presented in two steps. in the first step, the theoretical s-wave displacement spectra, conditioned by frequency-independent q, was fitted with the observed displacement spectra. therefore corner frequency, moment magnitude and frequency-independent q for each record were estimated simultaneously and the estimate of error is given in the root-mean-square sense over al...

Four large earthquakes occurred in 1980 in a seismic gap near the Loyalty Islands in the New Hebrides. At 3:25 UT on October 24 an event with M, = 6.7 initiated the sequence. Three events, M, = 6.7, 7.2, and 6.5, followed on the next day. We investigated this sequence by using the seismicity, first-motion, and wavefonn data and long-period surface waves. The first-motion data constrain one of e...

The local earthquake events recorded north of Panjal thrust (=Main Central thrust) and Main Boundary Thrust (MBT) by the four broadband seismological observatories located at Jammu, Poonch, Doru and Bani in Jammu and Kashmir from January to May, 2012 have coda magnitudes ranging from 1.7 to 3.8 were used to compute source parameters namely; seismic moment, source radius, and stress drop. These ...

We investigated the source characteristics of large earthquakes which occurred in the Michoacan, Mexico, seismic gap during the period from 1981 to 1986 in relation to historical seismicity in the region. The rupture pattern of the Michoacan gap during this period can be characterized by a sequential failure of five distinct asperities. Before 1981, the Michoacan gap had not experienced a large...

Short-period (SP) and long-period (LP) seismograms written by the main shock and two principal aftershocks of the 1976 Friuli, Italy, earthquake sequence are modeled in the t ime domain using synthetic seismograms. The main shock occurred on 6 May 1976 (20h OOm, Ms = 6.5) and both aftershocks on 15 September 1976 (03h 15m, Ms -6.0 and 09h 21m, Ms = 5 .9 ) , Source models were determined init ia...