The ANSS event ID is usp0008vh3 and the event page is at https://earthquake.usgs.gov/earthquakes/eventpage/usp0008vh3/executive.
1998/09/25 19:52:52 41.495 -80.388 5 4.47 Pennsylvania
USGS/SLU Moment Tensor Solution ENS 1998/09/25 19:52:52:0 41.495 -80.388 5.0 4.5 Pennsylvania Stations used: Filtering commands used: Best Fitting Double Couple Mo = 6.38e+22 dyne-cm Mw = 4.47 Z = 2 km Plane Strike Dip Rake NP1 13 71 159 NP2 110 70 20 Principal Axes: Axis Value Plunge Azimuth T 6.38e+22 28 331 N 0.00e+00 62 153 P -6.38e+22 1 62 Moment Tensor: (dyne-cm) Component Value Mxx 2.38e+22 Mxy -4.77e+22 Mxz 2.27e+22 Myy -3.79e+22 Myz -1.36e+22 Mzz 1.40e+22 ############-- ################------ ##### ############-------- ###### T ############--------- ######## ############---------- ########################---------- P #########################---------- -#########################-------------- ---#######################-------------- ------####################---------------- --------##################---------------- -----------###############---------------- --------------###########----------------- ------------------######---------------- -----------------------#---------------- ----------------------################ --------------------################ ------------------################ ---------------############### -------------############### ---------############# ---########### Global CMT Convention Moment Tensor: R T P 1.40e+22 2.27e+22 1.36e+22 2.27e+22 2.38e+22 4.77e+22 1.36e+22 4.77e+22 -3.79e+22 Details of the solution is found at http://www.eas.slu.edu/eqc/eqc_mt/MECH.NA/19980925195252/index.html |
STK = 110 DIP = 70 RAKE = 20 MW = 4.47 HS = 2
The NDK file is 19980925195252.ndk
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Older earthquake were studied using analog seismograms, which were digitized and analyzed. The original data are not longer available. However focal mechanism solutions based on the waveforms are given in published literature. At the same time, a given earthquake may have been analyzed independently, and the reference is given here.
For this earthquake the source reference is the following:
Maceira, M., C. J. Ammon and R. B. Herrmann (2000). Faulting parameters of the September 25, 1998 Pymatuning, Pennsylvania earthquake, Seism. Res. Letters 71, 742-752.
The CUS model used for the waveform synthetic seismograms and for the surface wave eigenfunctions and dispersion is as follows (The format is in the model96 format of Computer Programs in Seismology).
MODEL.01 CUS Model with Q from simple gamma values ISOTROPIC KGS FLAT EARTH 1-D CONSTANT VELOCITY LINE08 LINE09 LINE10 LINE11 H(KM) VP(KM/S) VS(KM/S) RHO(GM/CC) QP QS ETAP ETAS FREFP FREFS 1.0000 5.0000 2.8900 2.5000 0.172E-02 0.387E-02 0.00 0.00 1.00 1.00 9.0000 6.1000 3.5200 2.7300 0.160E-02 0.363E-02 0.00 0.00 1.00 1.00 10.0000 6.4000 3.7000 2.8200 0.149E-02 0.336E-02 0.00 0.00 1.00 1.00 20.0000 6.7000 3.8700 2.9020 0.000E-04 0.000E-04 0.00 0.00 1.00 1.00 0.0000 8.1500 4.7000 3.3640 0.194E-02 0.431E-02 0.00 0.00 1.00 1.00