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
ACTO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 476 3 x x x x x x x 1 x x x x x x x
ALFO-PO HHN HHE S 0001 2012.019 2013.317 0.0 90.0 409 1 x x -16 x x x x x x x x x x x x
ALGO-PO HHN HHE S 0004 2012.188 2015.365 0.0 90.0 921 22 x x x x x x -4 x x x x x x x x
BANO-PO HHN HHE S 0001 2012.009 2013.317 0.0 90.0 455 1 x x x x x -5 x x x x x x x x x
BASO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 476 33 x x x x x x x x x x x x x x 85
BELQ-PO HHN HHE S 0001 2012.137 2012.259 0.0 90.0 89 4 x x x x x -7 x x x x x x x x x
BMRO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 460 50 x x x x x -5 x x x x x x x x x
BRCO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 475 3 x x x x x x x x x x x x x 21 x
BUKO-PO HHN HHE S 0001 2012.016 2013.317 0.0 90.0 413 1 x x x x x x -3 x x x x x x x x
BWLO-PO HHN HHE S 0001 2012.001 2013.200 0.0 90.0 365 4 x x x x x x x x x x x x x x 56
CLWO-PO HHN HHE S 0001 2012.120 2013.317 0.0 90.0 240 1 x x x x x x x x 2 x x x x x x
DELO-PO HHN HHE S 0001 2012.014 2013.317 0.0 90.0 459 6 x x x x x x x x 2 x x x x x x
DRCO-PO HHN HHE S 0001 2012.137 2013.242 0.0 90.0 339 9 x x x x x x x -1 x x x x x x x
DRWO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 449 13 x x x x x -5 x x x x x x x x x
ELFO-PO HHN HHE S 0001 2012.001 2013.109 0.0 90.0 271 3 x x x x x x x x x x x 11 x x x
KLBO-PO HHN HHE S 0001 2012.009 2013.317 0.0 90.0 438 2 x x x x x x x x 3 x x x x x x
LATQ-PO HHN HHE S 0001 2012.137 2015.354 0.0 90.0 949 41 x x x x x x x -1 x x x x x x x
MEDO-PO HHN HHE S 0001 2012.015 2013.317 0.0 90.0 466 2 x x x x x x x 0 x x x x x x x
ORHO-PO HHN HHE S 0002 2012.137 2013.311 0.0 90.0 425 4 x x -19 x x x x x x x x x x x x
ORIO-PO HHN HHE S 0001 2012.137 2014.268 0.0 90.0 494 0 x x x x x x x x x x x x x x x
PECO-PO HHN HHE S 0001 2012.014 2013.311 0.0 90.0 237 0 x x x x x x x x x x x x x x x
PEMO-PO HHN HHE S 0001 2012.014 2013.317 0.0 90.0 455 3 x x x x x x -3 x x x x x x x x
PKRO-PO HHN HHE S 0001 2012.001 2013.275 0.0 90.0 444 12 x x x x x x -4 x x x x x x x x
PLIO-PO HHN HHE S 0001 2012.014 2013.317 0.0 90.0 234 0 x x x x x x x x x x x x x x x
PLVO-PO HHN HHE S 0001 2012.014 2013.317 0.0 90.0 461 1 -33 x x x x x x x x x x x x x x
STCO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 479 13 x x x x x x x 0 x x x x x x x
TOBO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 474 3 x x x x x x x 1 x x x x x x x
TORO-PO HHN HHE S 0001 2012.001 2013.317 0.0 90.0 467 0 x x x x x x x x x x x x x x x
TYNO-PO HHN HHE S 0001 2012.001 2013.298 0.0 90.0 442 4 x x x x x x x x 2 x x x x x x
WLVO-PO HHN HHE S 0001 2012.014 2013.277 0.0 90.0 425 18 x x x x x -7 x x x x x x x x x