Moment Tensor 20080303141114

Location

2008/03/03 14:11:14 13.40 125.70 24

Moment Tensor Comparison

For reference here are other moment tensor solutions for this event.

USGSMT USGSCMT GCMT

USGS Body-Wave Moment Tensor Solution 08/03/03 14:11:12.15 PHILIPPINE ISLANDS REGION Epicenter: 13.285 125.578 MW 6.8 USGS MOMENT TENSOR SOLUTION Depth 37 No. of sta: 52 Moment Tensor; Scale 10**19 Nm Mrr=-1.28 Mtt= 0.92 Mpp= 0.36 Mrt=-0.26 Mrp= 0.26 Mtp=-1.37 Principal axes: T Val= 2.08 Plg= 6 Azm=219 N -0.76 3 309 P -1.32 82 71 Best Double Couple:Mo=1.8*10**19 NP1:Strike=133 Dip=51 Slip= -85 NP2: 305 39 -96 ####### ################# ##################### ##---------############## ##----------------########### ###-------------------######### ####--------------------####### #####---------------------####### ######---------- ---------##### #######--------- P ----------#### ########-------- -----------### ##########--------------------### ###########------------------## #############-----------------# ###############-------------# # ##############------- T ################### ################# #######

USGS Centroid Moment Tensor Solution 08/03/03 14:11:12.15 PHILIPPINE ISLANDS REGION Epicenter: 13.285 125.578 MW 6.9 USGS CENTROID MOMENT TENSOR 08/03/03 14:11:33.09 Centroid: 13.568 126.013 Depth 25 No. of sta:107 Moment Tensor; Scale 10**19 Nm Mrr=-2.28 Mtt= 1.64 Mpp= 0.64 Mrt=-0.25 Mrp=-0.49 Mtp=-1.60 Principal axes: T Val= 2.82 Plg= 1 Azm= 36 N -0.38 15 126 P -2.44 74 302 Best Double Couple:Mo=2.6*10**19 NP1:Strike=111 Dip=46 Slip=-111 NP2: 322 48 -68 ####### ################# ----############### T -----------########## # ----------------############# -------------------############ ---------------------########## #----------- ---------######### ##---------- P ----------######## ###--------- -----------####### #####---------------------####### #######--------------------###### ########------------------##### ############---------------##-- ###################--#####--- #######################-- ##################### ################# #######

Magnitude 6.9 PHILIPPINE ISLANDS REGION Monday, March 03, 2008 at 14:11:14 UTC Global CMT Project Moment Tensor Solution March 3, 2008, PHILIPPINE ISLANDS REGION, MW=6.8 Liz Starin CENTROID-MOMENT-TENSOR SOLUTION GCMT EVENT: C200803031411A DATA: II IU CU IC G GE L.P.BODY WAVES: 93S, 226C, T= 50 MANTLE WAVES: 93S, 196C, T=125 SURFACE WAVES: 92S, 207C, T= 50 TIMESTAMP: Q-20080303151849 CENTROID LOCATION: ORIGIN TIME: 14:11:21.6 0.1 LAT:13.54N 0.00;LON:125.63E 0.00 DEP: 18.0 0.2;TRIANG HDUR: 6.5 MOMENT TENSOR: SCALE 10**26 D-CM RR=-1.850 0.012; TT= 1.460 0.009 PP= 0.387 0.010; RT= 0.126 0.029 RP= 0.524 0.032; TP=-1.610 0.008 PRINCIPAL AXES: 1.(T) VAL= 2.630;PLG= 3;AZM=216 2.(N) -0.580; 21; 307 3.(P) -2.053; 69; 119 BEST DBLE.COUPLE:M0= 2.34*10**26 NP1: STRIKE=285;DIP=46;SLIP=-120 NP2: STRIKE=145;DIP=51;SLIP= -62 ########### ################### --##################### ---######################## ----#------------############ --###------------------######## #####--------------------###### #######---------------------##### #######-----------------------### ########----------- ---------## #########---------- P ----------# #########--------- ---------- ###########-------------------- ###########------------------ #############-------------- ###########--------- T ################## ###########

Data set

The following broadband stations passed the QC and were used for the source inversion. AKUT ARMA COEN CRAG EGAK EIDS FORT MCQ MID NLWA OHAK PMR SDPT SIT SKAG SMY WRAK XMIS

Forward Synthetic

All observed and Greens function waveforms are corrected to instrument response to ground velocity in meters/sec for the passband of 0.004 - 5 Hz. The traces were then lowpass filtered at 0.25 Hz and interpolated to a sample rate of 1 second.

The moment tensor solution used has the parameters:

HS=37
STK=133
DIP=51
RAKE=-85
MW=6.8 

The Green's function closest to the desired depth was
DEP=0370 , where (DEP/10) is the computed depth.

The cut windows attempt to include the P, pP, sP, pS, S and sS arrivals. However, one must be very careful about the fact that PP may be included in some distance ranges.

The waveforms are then bandpass filtered by the application of the following high- and low-pass stages (an optional microseism filter):

hp c 0.0083 2
lp c 0.0250 2
int
br c 0.12 0.25 n 4 p 2

The traces were next integrated to ground displacement in meters. Finally the observed data are interpolated to have the same sampling at the Green's functions.
NOTE: this was done for speed. The proper sequence is to read traces, filter and then cut - gsac will be modified to introduce a command CUTWR to define the cut upon a write.

The following filter ranges are used according to the moment magnitude Mw:

   FILTER_BAND   1/FH(s)  1/FL(s)
       1           60     12      Mw < 6.4
       2          100     20      6.4 < Mw <= 6.9
       3          120     40      Mw > 6.9

The map displays the distribution of stations used for this source inversion.

Location of the earthquake (yellow star) and great circle path from the epicenter to each station (red) [created using GMT (Wessel, P., and W. H. F. Smith, New version of Generic Mapping Tools released, EOS Trans. AGU, 76 329, 1995.)]

Detailed Waveform Comparison

P-wave Z component

Observed (red) and predicted seismograms (blue) ordered by increasing epicentral distance. Each pair of traces is annotated with the wave type and a station identifier (station, network, and channel id's), epicentral distance in degrees, source-to-station azimuth in degrees. Each seismogram pair is plotted with the same scale and the peak amplitudes in meters are shown above to the left of each trace. The optimal time shift between the observed first arrival and the predicted first arrival (in seconds) is shown above the prediction on the right. Red circles flag seismograms with amplitude misfits of a factor of 2 or more.

SH-wave T component

SV-wave R component

Waveforms used

The following waveforms are used for the plot above. Note that the naming convention used by the generating program does not distinguish between LH, BH and HH channels. One can change the DOPZSTA, DOSHTSTA and DOSVRSTA scripts to preserve the component names.

AKUTATBHR AKUTATBHT AKUTATBHZ ARMAAUBHR ARMAAUBHT ARMAAUBHZ COENAUBHR COENAUBHT COENAUBHZ CRAGATBHR CRAGATBHT CRAGATBHZ EGAKUSBHR EGAKUSBHT EGAKUSBHZ EIDSAUBHR EIDSAUBHT EIDSAUBHZ FORTAUBHR FORTAUBHT FORTAUBHZ MCQAUBHR MCQAUBHT MCQAUBHZ MIDATBHR MIDATBHT MIDATBHZ NLWAUSBHR NLWAUSBHT NLWAUSBHZ OHAKATBHR OHAKATBHT OHAKATBHZ PMRATBHR PMRATBHT PMRATBHZ SDPTATBHR SDPTATBHT SDPTATBHZ SITATBHR SITATBHT SITATBHZ SKAGATBHR SKAGATBHT SKAGATBHZ SMYATBHR SMYATBHT SMYATBHZ WRAKUSBHR WRAKUSBHT WRAKUSBHZ WRAKUSHRBHR WRAKUSHRBHT WRAKUSHRBHZ XMISAUBHR XMISAUBHT XMISAUBHZ

Processing times

Starting Processing         : Wed Mar 12 17:03:53 UTC 2008
Starting query to get files : Wed Mar 12 17:03:53 UTC 2008
Starting deconvolution      : Wed Mar 12 17:05:48 UTC 2008
Starting trace rotation     : Wed Mar 12 17:07:22 UTC 2008
Starting distance selection : Wed Mar 12 17:07:39 UTC 2008
Starting trace QC           : Wed Mar 12 17:07:42 UTC 2008
Starting synthetic          : Wed Mar 12 17:07:42 UTC 2008
Starting documentation      : Wed Mar 12 17:08:00 UTC 2008
Processing Completion       : Wed Mar 12 17:08:00 UTC 2008

Last Changed Thu Mar 13 13:30:45 UTC 2008