Polarization anomalies at various stations


The table below shows the results from polarization analysis of long-period surface waves using the method described by Ekstrom and Busby (SRL, 2008). The horizontal components have been rotated to maximize the correlation between the observed and predicted seismograms for moderate and large earthquakes. The table shows the median (aqua blue) of the rotation angle (the anomaly), as well as the range (navy blue) for the second and third quartiles of the distribution of angles.

The table below gives the channel names and station orientation for the horizontal components, the wave type (Surface-wave or Mantle-wave), a response epoch identifier, the times of the first and last observations used, the total number of observations, and the number of polarization measurements used in the estimate of the sensor orientation. Estimates based on fewer than 5 measurements are less reliable. The orientation anomaly is measured against the reported orientation (Az-1, Az-2). A positive value for the anomaly reflects a counter-clockwise rotation of the sensor compared to the reported value.

Ranked by polarization anomaly

Ascii file with the data

Arrival-angle anomalies
Station Channels T Epoch min time max time Az-1 Az-2 # obs. # used -90- -26 -25- -21 -20- -16 -15- -11 -10- -8 -7- -5 -4- -2 -1- 1 2- 4 5- 7 8- 10 11- 15 16- 20 21- 25 26- 90
ANGG-DK LHN LHE S 0001 2010.214 2011.294 7.5 97.5 604 11 x x x x x x -3 x x x x x x x x
ANGG-DK LHN LHE S 0002 2011.296 2012.123 237.5 327.5 218 3 x x x x x x x x 2 x x x x x x
ANGG-DK LHN LHE S 0003 2012.124 2018.365 7.5 97.5 2605 58 x x x x x x x x x x 10 x x x x
DBG-DK LH1-00 LH2-00 S 0001 2013.013 2018.365 0.0 90.0 2457 256 x x x x x x x x 2 x x x x x x
DBG-DK LHN LHE S 0001 2010.224 2013.010 0.0 90.0 949 97 x x x x x x x 1 x x x x x x x
DY2G-DK LH1-00 LH2-00 S 0001 2013.010 2018.365 295.0 25.0 2456 237 x x x x x x x x 4 x x x x x x
DY2G-DK LH1-01 LH2-01 S 0001 2011.226 2012.159 295.0 25.0 339 23 x x x x x x x x 4 x x x x x x
DY2G-DK LH1-01 LH2-01 S 0002 2012.161 2013.009 295.0 25.0 231 22 x x x x x x x x x 5 x x x x x
DY2G-DK LH1-10 LH2-10 S 0001 2013.010 2018.365 0.0 90.0 2457 256 x x x x x x x x 3 x x x x x x
DY2G-DK LHN-02 LHE-02 S 0001 2011.226 2012.159 0.0 90.0 340 36 x x x x x x x x 3 x x x x x x
DY2G-DK LHN-02 LHE-02 S 0002 2012.161 2013.009 0.0 90.0 231 14 x x x x x x x x 3 x x x x x x
ICESG-DK LH1-00 LH2-00 S 0001 2013.005 2018.365 0.0 90.0 2460 227 x x x x x x -2 x x x x x x x x
ICESG-DK LHN LHE S 0001 2011.159 2013.010 0.0 90.0 677 73 x x x x x x -3 x x x x x x x x
ILULI-DK LHN LHE S 0001 2009.232 2018.365 0.0 90.0 3674 225 x x x x x x x x 2 x x x x x x
ISOG-DK LHN LHE S 0001 2012.252 2018.365 0.0 90.0 2195 42 x x x x x x x x x 5 x x x x x
KULLO-DK LHN LHE S 0001 2009.232 2018.365 0.0 90.0 3166 264 x x x x x x -2 x x x x x x x x
NEEM-DK LH1-00 LH2-00 S 0002 2013.005 2013.009 121.4 211.4 6 3 x x x x x x x 1 x x x x x x x
NEEM-DK LH1-00 LH2-00 S 0003 2013.010 2018.162 121.4 211.4 2090 393 x x x x x x x 0 x x x x x x x
NEEM-DK LH1-00 LH2-00 S 0004 2018.163 2018.365 121.4 211.4 270 18 x x x x x x x -1 x x x x x x x
NEEM-DK LH1-01 LH2-01 S 0001 2011.199 2012.198 121.4 211.4 404 40 x x x x x x x 0 x x x x x x x
NEEM-DK LH1-01 LH2-01 S 0002 2012.200 2013.009 121.4 211.4 195 37 x x x x x x x 1 x x x x x x x
NEEM-DK LH1-10 LH2-10 S 0002 2013.005 2013.009 0.0 90.0 6 0 x x x x x x x x x x x x x x x
NEEM-DK LH1-10 LH2-10 S 0003 2013.010 2018.162 0.0 90.0 2089 63 x x x x x x -3 x x x x x x x x
NEEM-DK LH1-10 LH2-10 S 0004 2018.163 2018.365 0.0 90.0 270 8 x x x x x x x 1 x x x x x x x
NEEM-DK LHN-02 LHE-02 S 0001 2011.199 2012.198 0.0 90.0 406 6 x x x x x x -2 x x x x x x x x
NEEM-DK LHN-02 LHE-02 S 0002 2012.200 2013.009 0.0 90.0 195 5 x x x x x x x -1 x x x x x x x
NOR-DK LHN LHE S 0001 2010.188 2018.365 0.0 90.0 3592 113 x x x x x x x 0 x x x x x x x
NRS-DK LHN LHE S 0001 2010.203 2015.235 0.0 90.0 2145 180 x x x x x x x x 3 x x x x x x
NRS-DK LHN LHE S 0002 2015.236 2018.365 0.0 90.0 1362 81 x x x x x x -2 x x x x x x x x
NUUG-DK LH1-00 LH2-00 S 0001 2017.252 2018.365 0.0 90.0 552 34 x x x x x x x 1 x x x x x x x
NUUG-DK LHN LHE S 0001 2010.203 2015.180 0.0 90.0 2061 106 x x x x x x x 0 x x x x x x x
NUUG-DK LHN LHE S 0002 2015.181 2017.173 79.0 169.0 794 2 x x x x x -6 x x x x x x x x x
NUUK-DK LH1-00 LH2-00 S 0001 2013.008 2018.365 0.0 90.0 2388 92 x x x x x x x x 2 x x x x x x
NUUK-DK LHN LHE S 0001 2010.209 2013.261 0.0 90.0 1382 47 x x x x x x x 1 x x x x x x x
SCO-DK LHN LHE S 0001 2010.220 2012.171 0.0 90.0 868 66 x x x x x x x -1 x x x x x x x
SCO-DK LHN LHE S 0002 2012.174 2018.365 0.0 90.0 2516 195 x x x x x x -2 x x x x x x x x
SOEG-DK LH1-00 LH2-00 S 0001 2013.005 2018.365 29.5 119.5 2466 156 x x x x x x x -1 x x x x x x x
SOEG-DK LH1 LH2 S 0001 2011.212 2012.364 29.5 119.5 505 30 x x x x x x x 1 x x x x x x x
TULEG-DK LHN LHE S 0001 2010.125 2011.118 0.0 90.0 433 4 x x x x x x x x x x 8 x x x x
TULEG-DK LHN LHE S 0002 2011.120 2018.365 0.0 90.0 3180 180 x x x x x x x x x 5 x x x x x