2010/03/24 14:11:33 38.786 40.211 18.7 4.90 Turkey
USGS Felt map for this earthquake
USGS/SLU Moment Tensor Solution
ENS 2010/03/24 14:11:33:8 38.79 40.21 18.7 4.9 Turkey
Stations used:
KO.AGRB KO.BAYT KO.BCA KO.CEYT KO.CLDR KO.CORM KO.CUKT
KO.DARE KO.DIKM KO.ERZN KO.ESPY KO.ILIC KO.KARA KO.KARS
KO.KOZT KO.KTUT KO.KVT KO.RSDY KO.SIRT KO.SVSK KO.URFA
KO.VANB KO.VRTB
Filtering commands used:
hp c 0.02 n 3
lp c 0.05 n 3
Best Fitting Double Couple
Mo = 2.63e+23 dyne-cm
Mw = 4.88
Z = 13 km
Plane Strike Dip Rake
NP1 138 71 137
NP2 245 50 25
Principal Axes:
Axis Value Plunge Azimuth
T 2.63e+23 43 94
N 0.00e+00 44 299
P -2.63e+23 13 196
Moment Tensor: (dyne-cm)
Component Value
Mxx -2.30e+23
Mxy -7.55e+22
Mxz 4.73e+22
Myy 1.20e+23
Myz 1.47e+23
Mzz 1.09e+23
--------------
----------------------
----------------------------
#-----------------------------
####------------------------------
######----------##################--
#######------#########################
#########--#############################
#########--#############################
########-----#############################
######--------################# ########
#####----------################ T ########
####-------------############## ########
##----------------######################
##------------------####################
---------------------#################
----------------------##############
-----------------------###########
-------------------------#####
------- ------------------
---- P ---------------
-----------
Global CMT Convention Moment Tensor:
R T P
1.09e+23 4.73e+22 -1.47e+23
4.73e+22 -2.30e+23 7.55e+22
-1.47e+23 7.55e+22 1.20e+23
Details of the solution is found at
http://www.eas.slu.edu/Earthquake_Center/MECH.NA/20100324141133/index.html
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STK = 245
DIP = 50
RAKE = 25
MW = 4.88
HS = 13.0
The waveform inversion is preferred.
The following compares this source inversion to others
USGS/SLU Moment Tensor Solution
ENS 2010/03/24 14:11:33:8 38.79 40.21 18.7 4.9 Turkey
Stations used:
KO.AGRB KO.BAYT KO.BCA KO.CEYT KO.CLDR KO.CORM KO.CUKT
KO.DARE KO.DIKM KO.ERZN KO.ESPY KO.ILIC KO.KARA KO.KARS
KO.KOZT KO.KTUT KO.KVT KO.RSDY KO.SIRT KO.SVSK KO.URFA
KO.VANB KO.VRTB
Filtering commands used:
hp c 0.02 n 3
lp c 0.05 n 3
Best Fitting Double Couple
Mo = 2.63e+23 dyne-cm
Mw = 4.88
Z = 13 km
Plane Strike Dip Rake
NP1 138 71 137
NP2 245 50 25
Principal Axes:
Axis Value Plunge Azimuth
T 2.63e+23 43 94
N 0.00e+00 44 299
P -2.63e+23 13 196
Moment Tensor: (dyne-cm)
Component Value
Mxx -2.30e+23
Mxy -7.55e+22
Mxz 4.73e+22
Myy 1.20e+23
Myz 1.47e+23
Mzz 1.09e+23
--------------
----------------------
----------------------------
#-----------------------------
####------------------------------
######----------##################--
#######------#########################
#########--#############################
#########--#############################
########-----#############################
######--------################# ########
#####----------################ T ########
####-------------############## ########
##----------------######################
##------------------####################
---------------------#################
----------------------##############
-----------------------###########
-------------------------#####
------- ------------------
---- P ---------------
-----------
Global CMT Convention Moment Tensor:
R T P
1.09e+23 4.73e+22 -1.47e+23
4.73e+22 -2.30e+23 7.55e+22
-1.47e+23 7.55e+22 1.20e+23
Details of the solution is found at
http://www.eas.slu.edu/Earthquake_Center/MECH.NA/20100324141133/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 0.02 n 3 lp c 0.05 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 50 65 -35 4.55 0.3385
WVFGRD96 1.0 55 85 -5 4.53 0.3549
WVFGRD96 2.0 230 65 -35 4.66 0.4242
WVFGRD96 3.0 230 55 -25 4.70 0.4471
WVFGRD96 4.0 230 45 -20 4.75 0.4714
WVFGRD96 5.0 235 40 -10 4.79 0.5029
WVFGRD96 6.0 235 40 -10 4.80 0.5278
WVFGRD96 7.0 245 45 15 4.80 0.5498
WVFGRD96 8.0 245 40 15 4.85 0.5638
WVFGRD96 9.0 245 40 15 4.86 0.5828
WVFGRD96 10.0 250 45 25 4.87 0.5979
WVFGRD96 11.0 250 45 30 4.88 0.6082
WVFGRD96 12.0 245 50 25 4.88 0.6131
WVFGRD96 13.0 245 50 25 4.88 0.6150
WVFGRD96 14.0 245 50 25 4.89 0.6133
WVFGRD96 15.0 245 50 20 4.89 0.6097
WVFGRD96 16.0 245 50 20 4.89 0.6042
WVFGRD96 17.0 245 55 20 4.89 0.5980
WVFGRD96 18.0 245 55 20 4.90 0.5906
WVFGRD96 19.0 245 55 20 4.90 0.5825
WVFGRD96 20.0 245 55 20 4.91 0.5733
WVFGRD96 21.0 245 55 20 4.92 0.5636
WVFGRD96 22.0 245 55 20 4.92 0.5532
WVFGRD96 23.0 245 55 20 4.92 0.5422
WVFGRD96 24.0 245 55 20 4.93 0.5309
WVFGRD96 25.0 245 55 15 4.93 0.5193
WVFGRD96 26.0 245 55 15 4.93 0.5077
WVFGRD96 27.0 155 80 35 4.93 0.5011
WVFGRD96 28.0 155 75 30 4.94 0.4959
WVFGRD96 29.0 330 85 -30 4.95 0.4881
The best solution is
WVFGRD96 13.0 245 50 25 4.88 0.6150
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 0.02 n 3 lp c 0.05 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=Wed Mar 24 20:40:31 CDT 2010