Location
KANDİLLİ Observ atory Location
Tarih Saat Enlem(N) Boylam(E) Derinlik(km) MD ML MS Yer Çözüm Niteliği
---------- -------- -------- ------- ---------- ------------ -------------- --------------
2011.05.19 23:15:22 39.1490 29.1025 7.0 -.- 5.9 -.- SİMAV (KÜTAHYA) İlksel
USGS Location
2011/05/19 20:15:23 39.115 29.124 4.6 6.00 Turkey
Arrival Times (from USGS)
Arrival time list
Felt Map
USGS Felt map for this earthquake
USGS Felt reports page for
Focal Mechanism
USGS/SLU Moment Tensor Solution
ENS 2011/05/19 20:15:23:0 39.12 29.12 4.6 6.0 Turkey
Stations used:
GE.ISP KO.ADVT KO.ARMT KO.BALB KO.BCK KO.BGKT KO.CAVI
KO.CTKS KO.EDC KO.ERIK KO.EZN KO.GELI KO.GEMT KO.GLHS
KO.GULT KO.HRTX KO.ISK KO.KCTX KO.KLYT KO.KRBG KO.KULA
KO.LADK KO.LAP KO.MDNY KO.MDUB KO.MRMT KO.RKY KO.SILT
KO.SPNC KO.SUTC KO.SVRH KO.TKR KO.YER
Filtering commands used:
hp c 0.02 n 3
lp c 0.10 n 3
Best Fitting Double Couple
Mo = 5.13e+24 dyne-cm
Mw = 5.74
Z = 13 km
Plane Strike Dip Rake
NP1 300 50 -60
NP2 78 48 -121
Principal Axes:
Axis Value Plunge Azimuth
T 5.13e+24 1 9
N 0.00e+00 23 100
P -5.13e+24 67 277
Moment Tensor: (dyne-cm)
Component Value
Mxx 4.98e+24
Mxy 9.12e+23
Mxz -1.56e+23
Myy -6.08e+23
Myz 1.81e+24
Mzz -4.37e+24
######### T ##
############# ######
############################
##############################
###-----------####################
--------------------################
-------------------------#############
----------------------------############
-------------------------------#########
-------------- ----------------########-
-------------- P ------------------#####--
-------------- -------------------###---
------------------------------------------
----------------------------------###---
##-----------------------------######---
####-----------------------##########-
########------------################
##################################
##############################
############################
######################
##############
Global CMT Convention Moment Tensor:
R T P
-4.37e+24 -1.56e+23 -1.81e+24
-1.56e+23 4.98e+24 -9.12e+23
-1.81e+24 -9.12e+23 -6.08e+23
Details of the solution is found at
http://www.eas.slu.edu/Earthquake_Center/MECH.NA/20110519201523/index.html
|
Preferred Solution
The preferred solution from an analysis of the surface-wave spectral amplitude radiation pattern, waveform inversion and first motion observations is
STK = 300
DIP = 50
RAKE = -60
MW = 5.74
HS = 13.0
The waveform inversion is preferred.
Moment Tensor Comparison
The following compares this source inversion to others
| SLU |
USGSMT |
USGS/SLU Moment Tensor Solution
ENS 2011/05/19 20:15:23:0 39.12 29.12 4.6 6.0 Turkey
Stations used:
GE.ISP KO.ADVT KO.ARMT KO.BALB KO.BCK KO.BGKT KO.CAVI
KO.CTKS KO.EDC KO.ERIK KO.EZN KO.GELI KO.GEMT KO.GLHS
KO.GULT KO.HRTX KO.ISK KO.KCTX KO.KLYT KO.KRBG KO.KULA
KO.LADK KO.LAP KO.MDNY KO.MDUB KO.MRMT KO.RKY KO.SILT
KO.SPNC KO.SUTC KO.SVRH KO.TKR KO.YER
Filtering commands used:
hp c 0.02 n 3
lp c 0.10 n 3
Best Fitting Double Couple
Mo = 5.13e+24 dyne-cm
Mw = 5.74
Z = 13 km
Plane Strike Dip Rake
NP1 300 50 -60
NP2 78 48 -121
Principal Axes:
Axis Value Plunge Azimuth
T 5.13e+24 1 9
N 0.00e+00 23 100
P -5.13e+24 67 277
Moment Tensor: (dyne-cm)
Component Value
Mxx 4.98e+24
Mxy 9.12e+23
Mxz -1.56e+23
Myy -6.08e+23
Myz 1.81e+24
Mzz -4.37e+24
######### T ##
############# ######
############################
##############################
###-----------####################
--------------------################
-------------------------#############
----------------------------############
-------------------------------#########
-------------- ----------------########-
-------------- P ------------------#####--
-------------- -------------------###---
------------------------------------------
----------------------------------###---
##-----------------------------######---
####-----------------------##########-
########------------################
##################################
##############################
############################
######################
##############
Global CMT Convention Moment Tensor:
R T P
-4.37e+24 -1.56e+23 -1.81e+24
-1.56e+23 4.98e+24 -9.12e+23
-1.81e+24 -9.12e+23 -6.08e+23
Details of the solution is found at
http://www.eas.slu.edu/Earthquake_Center/MECH.NA/20110519201523/index.html
|
USGS/SLU Regional Moment Solution
WESTERN TURKEY
11/05/19 20:15:24.42
Epicenter: 39.104 29.099
MW 5.8
USGS/SLU REGIONAL MOMENT TENSOR
Depth 11 No. of sta: 24
Moment Tensor; Scale 10**17 Nm
Mrr=-5.05 Mtt= 6.23
Mpp=-1.17 Mrt= 2.07
Mrp= 1.90 Mtp=-2.31
Principal axes:
T Val= 7.08 Plg= 7 Azm= 14
N -0.62 27 280
P -6.46 62 118
Best Double Couple:Mo=6.8*10**17
NP1:Strike=131 Dip=44 Slip= -50
NP2: 262 58 -122
|
Waveform Inversion
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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Location of broadband stations used for waveform inversion
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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 0.10 n 3
The results of this grid search from 0.5 to 19 km depth are as follow:
DEPTH STK DIP RAKE MW FIT
WVFGRD96 0.5 280 50 -90 5.32 0.3150
WVFGRD96 1.0 275 45 90 5.35 0.2814
WVFGRD96 2.0 100 45 95 5.48 0.3420
WVFGRD96 3.0 120 25 -55 5.53 0.2784
WVFGRD96 4.0 25 15 20 5.53 0.3368
WVFGRD96 5.0 265 80 75 5.54 0.3985
WVFGRD96 6.0 30 20 30 5.55 0.4428
WVFGRD96 7.0 340 50 40 5.62 0.4743
WVFGRD96 8.0 265 75 75 5.65 0.4972
WVFGRD96 9.0 265 70 75 5.67 0.5109
WVFGRD96 10.0 345 50 45 5.73 0.5194
WVFGRD96 11.0 340 55 40 5.74 0.5215
WVFGRD96 12.0 300 50 -60 5.73 0.5213
WVFGRD96 13.0 300 50 -60 5.74 0.5280
WVFGRD96 14.0 305 55 -55 5.76 0.5272
WVFGRD96 15.0 125 55 -50 5.77 0.5223
WVFGRD96 16.0 125 55 -50 5.78 0.5118
WVFGRD96 17.0 125 55 -50 5.79 0.4969
WVFGRD96 18.0 135 45 -35 5.79 0.4796
WVFGRD96 19.0 140 40 -30 5.79 0.4616
WVFGRD96 20.0 145 40 -20 5.80 0.4443
WVFGRD96 21.0 145 40 -20 5.81 0.4281
WVFGRD96 22.0 145 40 -20 5.82 0.4101
WVFGRD96 23.0 150 40 -10 5.83 0.3932
WVFGRD96 24.0 150 40 -10 5.83 0.3764
WVFGRD96 25.0 150 35 -10 5.83 0.3602
WVFGRD96 26.0 150 35 -10 5.84 0.3445
WVFGRD96 27.0 150 35 -10 5.85 0.3294
WVFGRD96 28.0 150 35 -10 5.85 0.3144
WVFGRD96 29.0 150 35 -10 5.86 0.2995
The best solution is
WVFGRD96 13.0 300 50 -60 5.74 0.5280
The mechanism correspond to the best fit is
|
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Figure 1. Waveform inversion focal mechanism
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The best fit as a function of depth is given in the following figure:
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Figure 2. Depth sensitivity for waveform mechanism
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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 component is plotted to the same scale and peak amplitudes are indicated by the numbers to the left of each trace. A pair of numbers is given in black at the right of each predicted traces. The upper number 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 lower number gives the percentage of variance reduction to characterize the individual goodness of fit (100% indicates a perfect fit).
The bandpass filter used in the processing and for the display was
hp c 0.02 n 3
lp c 0.10 n 3
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Figure 3. Waveform comparison for selected depth
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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.
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A check on the assumed source location is possible by looking at the time shifts between the observed and predicted traces. The time shifts for waveform matching arise for several reasons:
- The origin time and epicentral distance are incorrect
- The velocity model used for the inversion is incorrect
- The velocity model used to define the P-arrival time is not the
same as the velocity model used for the waveform inversion
(assuming that the initial trace alignment is based on the
P arrival time)
Assuming only a mislocation, the time shifts are fit to a functional form:
Time_shift = A + B cos Azimuth + C Sin Azimuth
The time shifts for this inversion lead to the next figure:
The derived shift in origin time and epicentral coordinates are given at the bottom of the figure.
Discussion
Velocity Model
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
Quality Control
Here we tabulate the reasons for not using certain digital data sets
The following stations did not have a valid response files:
DATE=Thu May 19 17:19:00 CDT 2011
Last Changed 2011/05/19