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
ANWB-CU LH1-00 LH2-00 M 0001 2010.049 2015.149 0.0 90.0 271 25 x x x x x x -2 x x x x x x x x
ANWB-CU LHN LHE M 0001 2007.253 2010.012 0.0 90.0 124 8 x x x x x -6 x x x x x x x x x
BBGH-CU LH1-00 LH2-00 M 0001 2010.049 2013.166 0.0 90.0 179 18 x x x x x x x 1 x x x x x x x
BBGH-CU LH1-00 LH2-00 M 0002 2013.175 2015.149 0.0 90.0 103 15 x x x x x x x 1 x x x x x x x
BBGH-CU LHN LHE M 0001 2006.271 2007.304 330.0 60.0 54 10 x x x x x x x -1 x x x x x x x
BBGH-CU LHN LHE M 0002 2007.314 2010.012 0.0 90.0 108 10 x x x x x x x 1 x x x x x x x
BCIP-CU LH1-00 LH2-00 M 0001 2010.049 2015.047 0.0 90.0 251 6 x x x x x -6 x x x x x x x x x
BCIP-CU LH1-00 LH2-00 M 0002 2015.058 2015.149 0.0 90.0 18 0 x x x x x x x x x x x x x x x
BCIP-CU LHN LHE M 0001 2006.360 2010.012 0.0 90.0 154 9 x x x x x x x -1 x x x x x x x
GRGR-CU LH1-00 LH2-00 M 0001 2010.049 2015.149 0.0 90.0 278 12 x x x x x x x -1 x x x x x x x
GRGR-CU LHN LHE M 0001 2006.360 2010.012 0.0 90.0 154 8 x x x x x x x x 3 x x x x x x
GRTK-CU LH1-00 LH2-00 M 0001 2010.049 2015.149 0.0 90.0 269 8 x x x x x x x 0 x x x x x x x
GRTK-CU LHN LHE M 0001 2008.005 2010.012 0.0 90.0 82 2 x x x x x x -3 x x x x x x x x
GTBY-CU LH1-00 LH2-00 M 0001 2010.049 2015.047 0.0 90.0 254 21 x x x x x x x x x 6 x x x x x
GTBY-CU LH1-00 LH2-00 M 0002 2015.058 2015.149 0.0 90.0 18 2 x x x x x x x x x x x x x x x
GTBY-CU LHN LHE M 0001 2007.245 2010.012 0.0 90.0 124 6 x x x x x x x x x 5 x x x x x
MTDJ-CU LH1-00 LH2-00 M 0001 2010.049 2015.149 0.0 90.0 272 24 x x x x x x x 1 x x x x x x x
MTDJ-CU LHN LHE M 0001 2007.350 2010.012 0.0 90.0 93 10 x x x x x x x -1 x x x x x x x
SDDR-CU LH1-00 LH2-00 M 0001 2010.049 2015.149 0.0 90.0 269 30 x x x x x x x 0 x x x x x x x
SDDR-CU LHN LHE M 0001 2007.013 2010.012 0.0 90.0 121 16 x x x x x x x 1 x x x x x x x
TGUH-CU LH1-00 LH2-00 M 0001 2010.163 2015.149 24.0 114.0 253 19 x x x x x x x x x x x x x 25 x
TGUH-CU LHN LHE M 0001 2006.271 2008.063 4.0 94.0 83 5 x x x x x x x x x 5 x x x x x
TGUH-CU LHN LHE M 0002 2008.080 2010.151 0.0 90.0 92 6 x x x x x x -2 x x x x x x x x