[IGSMAIL-6359] Predicted displacements for Japan earthquake

[Jeff Freymueller]

I have computed displacements predicted by the USGS finite fault model  
(by Gavin Hayes, USGS NEIC, see http://earthquake.usgs.gov/earthquakes/eqinthenews/2011/usc0001xgp/finite_fault.php) 
. I used a half-space approximation and the Coulomb software also from  
USGS. Based on the results from the Maule earthquake, this computation  
is probably fairly good in the far field, but large misfits could be  
possible for sites that have large displacements, because these are  
more sensitive to details of the slip distribution that might not be  
captured well in a model based on teleseismic data.

Displacements are given below in meters, east and north. In addition  
to the large displacements in Japan, predicted displacements are ~3 cm  
across Korea, 1-2 cm at IGS sites in eastern China (BJFS, CHAN, SHAO).  
I did not compute WUHN, but a measurable displacement is likely.

138.362000 36.133000 0.402313 -0.004257  0.0 0.0 0.0  USU3
140.087000 36.106000 0.595621 0.079876  0.0 0.0 0.0  TSKB
135.937000 33.577000 0.061559 0.014876  0.0 0.0 0.0  SHIM
141.133000 39.135000 3.200458 -1.626276  0.0 0.0 0.0  MIZU
115.892000 39.608000 0.012619 -0.002207  0.0 0.0 0.0  BJFS
121.200000 31.099000 0.011113 0.000914  0.0 0.0 0.0  SHAO
120.987000 24.797000 0.004463 0.000703  0.0 0.0 0.0  TNML
127.374000 36.399000 0.036044 -0.001711  0.0 0.0 0.0  DAEJ
127.054000 37.275000 0.036899 -0.003341  0.0 0.0 0.0  SUWN
125.444000 43.790000 0.026590 -0.010583  0.0 0.0 0.0  CHAN
127.024000 37.077000 0.036286 -0.002942  0.0 0.0 0.0  OSN1
142.717000 47.030000 0.006995 -0.008368  0.0 0.0 0.0  YSSK
135.046000 48.521000 0.018645 -0.017880  0.0 0.0 0.0  KHAJ
142.185000 27.096000 -0.005881 0.002845  0.0 0.0 0.0  CCJM
135.077000 48.489000 0.018761 -0.018004  0.0 0.0 0.0  KHAB
141.845000 43.529000 0.031466 -0.052657  0.0 0.0 0.0  STK2
142.065000 49.076000 0.005735 -0.006642  0.0 0.0 0.0  UGLG
142.717000 47.030000 0.006995 -0.008368  0.0 0.0 0.0  YUZN
147.873000 45.231000 -0.006909 0.002565  0.0 0.0 0.0  ITUR
145.861000 44.035000 -0.005280 0.005086  0.0 0.0 0.0  KUNA
146.833000 43.871000 -0.010586 0.004797  0.0 0.0 0.0  SHIK
149.402000 45.580000 -0.008464 0.001444  0.0 0.0 0.0  VDLN
142.195000 27.068000 -0.005862 0.002850  0.0 0.0 0.0  CCJ2

I have put a plot of the displacements on the web. Note that there are  
different scales for the red and blue vectors (blue for the  
displacements > 10 cm).

http://www.gps.alaska.edu/jeff/tohoku.png

Jeff

Dr. Jeffrey T. Freymueller         Office: 907-474-7286
Geophysical Institute              Fax:    907-474-7290
University of Alaska, Fairbanks    Home:   907-479-3550
PO Box 757320                      Cell:   907-378-7556
Fairbanks, AK 99775-7320           email: jeff.freymueller at gi.alaska.edu
URL: http://www.gps.alaska.edu/jeff/jeff.html

Download Alaska GPS data: ftp://gps.alaska.edu/pub/gpsdata/