1 DATE ORIGIN LAT N LONG E DEPTH MAG NO GAP DMIN RMS ERH ERZ Q M 990308 232 31.66 38-48.42 40- 5.99 0.15 0.00 46 41 54.3 0.75 1.7 0.8 D 1
DATE TIME LAT LON H
2010/03/08 02:32:32 38.807 40.099 0.15
2010/03/08 02:32:35 38.866 39.974 10.0 5.90 Turkey
USGS Felt map for this earthquake
USGS/SLU Moment Tensor Solution
ENS 2010/03/08 02:32:35:0 38.87 39.97 10.0 5.9 Turkey
Stations used:
GE.MALT KO.AFSR KO.AGRB KO.BAYT KO.BNN KO.CANT KO.CEYT
KO.CLDR KO.CORM KO.CUKT KO.DARE KO.DIKM KO.ILIC KO.KARA
KO.KARS KO.KMRS KO.KONT KO.KTUT KO.LADK KO.LOD KO.MERS
KO.RSDY KO.SIRT KO.SVSK KO.URFA
Filtering commands used:
hp c 0.01 n 3
lp c 0.04 n 3
Best Fitting Double Couple
Mo = 8.32e+24 dyne-cm
Mw = 5.88
Z = 9 km
Plane Strike Dip Rake
NP1 313 71 159
NP2 50 70 20
Principal Axes:
Axis Value Plunge Azimuth
T 8.32e+24 28 271
N 0.00e+00 62 93
P -8.32e+24 1 2
Moment Tensor: (dyne-cm)
Component Value
Mxx -8.31e+24
Mxy -3.75e+23
Mxz -4.89e+22
Myy 6.48e+24
Myz -3.45e+24
Mzz 1.83e+24
------ P -----
---------- ---------
----------------------------
#-----------------------------
########-------------------------#
#############--------------------###
################-----------------#####
####################-------------#######
######################---------#########
#### ##################------###########
#### T ####################--#############
#### #####################-#############
##########################----############
######################---------#########
####################------------########
################----------------######
############--------------------####
#######-------------------------##
------------------------------
----------------------------
----------------------
--------------
Global CMT Convention Moment Tensor:
R T P
1.83e+24 -4.89e+22 3.45e+24
-4.89e+22 -8.31e+24 3.75e+23
3.45e+24 3.75e+23 6.48e+24
Details of the solution is found at
http://www.eas.slu.edu/Earthquake_Center/MECH.NA/20100308023235/index.html
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STK = 50
DIP = 70
RAKE = 20
MW = 5.88
HS = 9.0
The waveform inversion is preferred.
The following compares this source inversion to others
USGS/SLU Moment Tensor Solution
ENS 2010/03/08 02:32:35:0 38.87 39.97 10.0 5.9 Turkey
Stations used:
GE.MALT KO.AFSR KO.AGRB KO.BAYT KO.BNN KO.CANT KO.CEYT
KO.CLDR KO.CORM KO.CUKT KO.DARE KO.DIKM KO.ILIC KO.KARA
KO.KARS KO.KMRS KO.KONT KO.KTUT KO.LADK KO.LOD KO.MERS
KO.RSDY KO.SIRT KO.SVSK KO.URFA
Filtering commands used:
hp c 0.01 n 3
lp c 0.04 n 3
Best Fitting Double Couple
Mo = 8.32e+24 dyne-cm
Mw = 5.88
Z = 9 km
Plane Strike Dip Rake
NP1 313 71 159
NP2 50 70 20
Principal Axes:
Axis Value Plunge Azimuth
T 8.32e+24 28 271
N 0.00e+00 62 93
P -8.32e+24 1 2
Moment Tensor: (dyne-cm)
Component Value
Mxx -8.31e+24
Mxy -3.75e+23
Mxz -4.89e+22
Myy 6.48e+24
Myz -3.45e+24
Mzz 1.83e+24
------ P -----
---------- ---------
----------------------------
#-----------------------------
########-------------------------#
#############--------------------###
################-----------------#####
####################-------------#######
######################---------#########
#### ##################------###########
#### T ####################--#############
#### #####################-#############
##########################----############
######################---------#########
####################------------########
################----------------######
############--------------------####
#######-------------------------##
------------------------------
----------------------------
----------------------
--------------
Global CMT Convention Moment Tensor:
R T P
1.83e+24 -4.89e+22 3.45e+24
-4.89e+22 -8.31e+24 3.75e+23
3.45e+24 3.75e+23 6.48e+24
Details of the solution is found at
http://www.eas.slu.edu/Earthquake_Center/MECH.NA/20100308023235/index.html
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The focal mechanism was determined using broadband seismic waveforms. The location of the event and the and stations used for the waveform inversion are shown in the next figure.
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The program wvfgrd96 was used with good traces observed at short distance to determine the focal mechanism, depth and seismic moment. This technique requires a high quality signal and well determined velocity model for the Green functions. To the extent that these are the quality data, this type of mechanism should be preferred over the radiation pattern technique which requires the separate step of defining the pressure and tension quadrants and the correct strike.
The observed and predicted traces are filtered using the following gsac commands:
hp c 0.01 n 3 lp c 0.04 n 3The results of this grid search from 0.5 to 19 km depth are as follow:
DEPTH STK DIP RAKE MW FIT
WVFGRD96 0.5 45 90 15 5.62 0.3873
WVFGRD96 1.0 45 90 10 5.64 0.4136
WVFGRD96 2.0 45 90 15 5.71 0.4801
WVFGRD96 3.0 45 90 15 5.75 0.5143
WVFGRD96 4.0 45 90 15 5.77 0.5352
WVFGRD96 5.0 45 85 15 5.80 0.5493
WVFGRD96 6.0 50 70 15 5.83 0.5620
WVFGRD96 7.0 50 70 15 5.84 0.5732
WVFGRD96 8.0 50 70 20 5.87 0.5799
WVFGRD96 9.0 50 70 20 5.88 0.5832
WVFGRD96 10.0 50 70 20 5.89 0.5827
WVFGRD96 11.0 50 70 15 5.90 0.5802
WVFGRD96 12.0 50 70 15 5.90 0.5763
WVFGRD96 13.0 50 65 15 5.91 0.5721
WVFGRD96 14.0 50 65 15 5.92 0.5691
WVFGRD96 15.0 50 65 15 5.92 0.5651
WVFGRD96 16.0 50 65 15 5.93 0.5602
WVFGRD96 17.0 50 70 15 5.93 0.5551
WVFGRD96 18.0 50 70 15 5.93 0.5492
WVFGRD96 19.0 50 70 15 5.94 0.5428
WVFGRD96 20.0 50 70 15 5.94 0.5360
WVFGRD96 21.0 50 70 15 5.95 0.5283
WVFGRD96 22.0 50 70 15 5.95 0.5206
WVFGRD96 23.0 50 70 10 5.96 0.5131
WVFGRD96 24.0 50 70 10 5.96 0.5055
WVFGRD96 25.0 50 70 10 5.97 0.4979
WVFGRD96 26.0 50 70 5 5.97 0.4907
WVFGRD96 27.0 50 70 5 5.98 0.4839
WVFGRD96 28.0 50 70 5 5.98 0.4769
WVFGRD96 29.0 50 70 5 5.99 0.4703
The best solution is
WVFGRD96 9.0 50 70 20 5.88 0.5832
The mechanism correspond to the best fit is
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The best fit as a function of depth is given in the following figure:
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The comparison of the observed and predicted waveforms is given in the next figure. The red traces are the observed and the blue are the predicted. Each observed-predicted componnet is plotted to the same scale and peak amplitudes are indicated by the numbers to the left of each trace. The number in black at the rightr of each predicted traces it the time shift required for maximum correlation between the observed and predicted traces. This time shift is required because the synthetics are not computed at exactly the same distance as the observed and because the velocity model used in the predictions may not be perfect. A positive time shift indicates that the prediction is too fast and should be delayed to match the observed trace (shift to the right in this figure). A negative value indicates that the prediction is too slow. The bandpass filter used in the processing and for the display was
hp c 0.01 n 3 lp c 0.04 n 3
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| Focal mechanism sensitivity at the preferred depth. The red color indicates a very good fit to thewavefroms. Each solution is plotted as a vector at a given value of strike and dip with the angle of the vector representing the rake angle, measured, with respect to the upward vertical (N) in the figure. |
The WUS used for the waveform synthetic seismograms and for the surface wave eigenfunctions and dispersion is as follows:
MODEL.01
Model after 8 iterations
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
1.9000 3.4065 2.0089 2.2150 0.302E-02 0.679E-02 0.00 0.00 1.00 1.00
6.1000 5.5445 3.2953 2.6089 0.349E-02 0.784E-02 0.00 0.00 1.00 1.00
13.0000 6.2708 3.7396 2.7812 0.212E-02 0.476E-02 0.00 0.00 1.00 1.00
19.0000 6.4075 3.7680 2.8223 0.111E-02 0.249E-02 0.00 0.00 1.00 1.00
0.0000 7.9000 4.6200 3.2760 0.164E-10 0.370E-10 0.00 0.00 1.00 1.00
Here we tabulate the reasons for not using certain digital data sets
The following stations did not have a valid response files:
DATE=Mon Mar 8 17:24:29 CST 2010