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 M 0001 2010.216 2011.294 7.5 97.5 66 3 x x x x x x -4 x x x x x x x x
ANGG-DK LHN LHE M 0002 2011.296 2012.119 237.5 327.5 27 1 x x x x x x x 1 x x x x x x x
ANGG-DK LHN LHE M 0003 2012.149 2018.363 7.5 97.5 304 13 x x x x x x x x x 6 x x x x x
DBG-DK LH1-00 LH2-00 M 0001 2013.030 2018.363 0.0 90.0 294 51 x x x x x x x 1 x x x x x x x
DBG-DK LHN LHE M 0001 2010.224 2013.005 0.0 90.0 100 15 x x x x x x x 1 x x x x x x x
DY2G-DK LH1-00 LH2-00 M 0001 2013.030 2018.363 295.0 25.0 295 50 x x x x x x x x 3 x x x x x x
DY2G-DK LH1-01 LH2-01 M 0001 2011.232 2012.149 295.0 25.0 43 4 x x x x x x x 1 x x x x x x x
DY2G-DK LH1-01 LH2-01 M 0002 2012.208 2013.005 295.0 25.0 22 3 x x x x x x x x 4 x x x x x x
DY2G-DK LH1-10 LH2-10 M 0001 2013.030 2018.363 0.0 90.0 295 52 x x x x x x x x 2 x x x x x x
DY2G-DK LHN-02 LHE-02 M 0001 2011.232 2012.149 0.0 90.0 43 3 x x x x x x x x x 7 x x x x x
DY2G-DK LHN-02 LHE-02 M 0002 2012.208 2013.005 0.0 90.0 22 2 x x x x x x x x 2 x x x x x x
ICESG-DK LH1-00 LH2-00 M 0001 2013.005 2018.363 0.0 90.0 296 46 x x x x x x -2 x x x x x x x x
ICESG-DK LHN LHE M 0001 2011.171 2013.005 0.0 90.0 73 17 x x x x x x -2 x x x x x x x x
ILULI-DK LHN LHE M 0001 2009.240 2018.363 0.0 90.0 421 52 x x x x x x x x 2 x x x x x x
ISOG-DK LHN LHE M 0001 2012.270 2018.363 0.0 90.0 268 11 x x x x x x x x 2 x x x x x x
KULLO-DK LHN LHE M 0001 2009.240 2018.363 0.0 90.0 379 55 x x x x x x -2 x x x x x x x x
NEEM-DK LH1-00 LH2-00 M 0002 2013.005 2013.005 121.4 211.4 1 1 x x x x x -5 x x x x x x x x x
NEEM-DK LH1-00 LH2-00 M 0003 2013.030 2018.124 121.4 211.4 253 80 x x x x x x x -1 x x x x x x x
NEEM-DK LH1-00 LH2-00 M 0004 2018.209 2018.363 121.4 211.4 35 1 x x x x x -7 x x x x x x x x x
NEEM-DK LH1-01 LH2-01 M 0001 2011.210 2012.149 121.4 211.4 45 2 x x x x x x x 1 x x x x x x x
NEEM-DK LH1-01 LH2-01 M 0002 2012.208 2013.005 121.4 211.4 22 5 x x x x x x -4 x x x x x x x x
NEEM-DK LH1-10 LH2-10 M 0002 2013.005 2013.005 0.0 90.0 1 0 x x x x x x x x x x x x x x x
NEEM-DK LH1-10 LH2-10 M 0003 2013.030 2018.124 0.0 90.0 253 0 x x x x x x x x x x x x x x x
NEEM-DK LH1-10 LH2-10 M 0004 2018.209 2018.363 0.0 90.0 35 0 x x x x x x x x x x x x x x x
NEEM-DK LHN-02 LHE-02 M 0001 2011.210 2012.149 0.0 90.0 45 0 x x x x x x x x x x x x x x x
NEEM-DK LHN-02 LHE-02 M 0002 2012.208 2013.005 0.0 90.0 22 0 x x x x x x x x x x x x x x x
NOR-DK LHN LHE M 0001 2010.195 2018.363 0.0 90.0 421 16 x x x x x x x -1 x x x x x x x
NRS-DK LHN LHE M 0001 2010.204 2015.224 0.0 90.0 256 62 x x x x x x x x 3 x x x x x x
NRS-DK LHN LHE M 0002 2015.256 2018.363 0.0 90.0 157 25 x x x x x x x -1 x x x x x x x
NUUG-DK LH1-00 LH2-00 M 0001 2017.262 2018.363 0.0 90.0 63 5 x x x x x x x -1 x x x x x x x
NUUG-DK LHN LHE M 0001 2010.204 2015.174 0.0 90.0 246 27 x x x x x x -2 x x x x x x x x
NUUG-DK LHN LHE M 0002 2015.191 2017.173 79.0 169.0 92 0 x x x x x x x x x x x x x x x
NUUK-DK LH1-00 LH2-00 M 0001 2013.030 2018.363 0.0 90.0 291 24 x x x x x x x 1 x x x x x x x
NUUK-DK LHN LHE M 0001 2010.210 2013.247 0.0 90.0 153 8 x x x x x x x x 4 x x x x x x
SCO-DK LHN LHE M 0001 2010.222 2012.149 0.0 90.0 93 8 x x x x x x x x 2 x x x x x x
SCO-DK LHN LHE M 0002 2012.208 2018.363 0.0 90.0 303 48 x x x x x x x 0 x x x x x x x
SOEG-DK LH1-00 LH2-00 M 0001 2013.005 2018.363 29.5 119.5 296 42 x x x x x x x 0 x x x x x x x
SOEG-DK LH1 LH2 M 0001 2011.212 2012.356 29.5 119.5 64 5 x x x x x x x 0 x x x x x x x
TULEG-DK LHN LHE M 0001 2010.125 2011.113 0.0 90.0 57 1 x x x x x x x x x 5 x x x x x
TULEG-DK LHN LHE M 0002 2011.130 2018.363 0.0 90.0 370 34 x x x x x x x x 4 x x x x x x