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
ALQ-HG LHN LHE M 0005 1976.035 1976.199 180.0 90.0 22 4 x x x x x x x 0 x x x x x x x
ALQ-HG LHN LHE M 0006 1976.209 1978.198 0.0 90.0 73 4 x x x x x -6 x x x x x x x x x
CHG-HG LHN LHE M 0003 1976.001 1976.023 0.0 90.0 5 0 x x x x x x x x x x x x x x x
CHG-HG LHN LHE M 0004 1976.035 1976.230 0.0 90.0 26 2 x x x x x -7 x x x x x x x x x
CTA-HG LHN LHE M 0002 1976.001 1976.035 0.0 90.0 6 0 x x x x x x x x x x x x x x x
CTA-HG LHN LHE M 0003 1976.084 1976.230 0.0 90.0 26 2 x x x x x x -3 x x x x x x x x
EIL-HG LHN LHE M 0002 1976.014 1976.138 0.0 90.0 14 0 x x x x x x x x x x x x x x x
EIL-HG LHN LHE M 0003 1976.150 1978.266 0.0 90.0 74 3 x x x x x x x x x x 8 x x x x
KIP-HG LHN LHE M 0003 1976.001 1976.014 0.0 90.0 3 1 x x x x x x x 0 x x x x x x x
KIP-HG LHN LHE M 0004 1976.035 1976.138 0.0 90.0 11 0 x x x x x x x x x x x x x x x
KIP-HG LHN LHE M 0005 1976.150 1978.346 0.0 90.0 95 1 x x x x x x x x 2 x x x x x x
KON-HG LHN LHE M 0003 1976.001 1976.001 0.0 90.0 1 0 x x x x x x x x x x x x x x x
KON-HG LHN LHE M 0004 1976.014 1976.125 0.0 90.0 12 1 x x x -13 x x x x x x x x x x x
KON-HG LHN LHE M 0005 1976.155 1976.178 0.0 90.0 5 1 x x x x x x -4 x x x x x x x x
KON-HG LHN LHE M 0006 1976.274 1977.068 0.0 90.0 16 3 x x x x x -5 x x x x x x x x x
KON-HG LHN LHE M 0007 1977.077 1977.080 0.0 90.0 2 0 x x x x x x x x x x x x x x x
KON-HG LHN LHE M 0008 1977.133 1977.247 0.0 90.0 15 0 x x x x x x x x x x x x x x x
KON-HG LHN LHE M 0009 1977.327 1978.198 0.0 90.0 28 3 x x x x x x x 1 x x x x x x x
MAT-HG LHN LHE M 0002 1976.014 1976.035 0.0 90.0 5 0 x x x x x x x x x x x x x x x
MAT-HG LHN LHE M 0003 1976.046 1976.084 0.0 90.0 3 0 x x x x x x x x x x x x x x x
MAT-HG LHN LHE M 0004 1976.089 1976.199 0.0 90.0 19 1 x x x x x x -4 x x x x x x x x
MAT-HG LHN LHE M 0005 1976.209 1976.230 0.0 90.0 6 0 x x x x x x x x x x x x x x x
MAT-HG LHN LHE M 0006 1976.274 1976.312 0.0 90.0 4 0 x x x x x x x x x x x x x x x
MAT-HG LHN LHE M 0007 1976.323 1977.092 0.0 90.0 9 0 x x x x x x x x x x x x x x x
OGD-HG LHN LHE M 0002 1976.001 1976.046 0.0 90.0 7 1 x x x x x x x x x 5 x x x x x
OGD-HG LHN LHE M 0003 1976.064 1976.100 0.0 90.0 5 1 x x x x x x x x 3 x x x x x x
OGD-HG LHN LHE M 0004 1976.125 1976.159 0.0 90.0 8 3 x x x x x x x x 4 x x x x x x
OGD-HG LHN LHE M 0005 1976.215 1979.016 0.0 90.0 82 8 x x x x x x x x x 7 x x x x x
TLO-HG LHN LHE M 0002 1976.001 1976.001 0.0 90.0 1 0 x x x x x x x x x x x x x x x
TLO-HG LHN LHE M 0003 1976.035 1976.172 0.0 90.0 16 1 x x x x x x x x x x 10 x x x x
TLO-HG LHN LHE M 0004 1976.177 1976.274 0.0 90.0 9 0 x x x x x x x x x x x x x x x
TLO-HG LHN LHE M 0005 1976.312 1978.204 0.0 90.0 26 0 x x x x x x x x x x x x x x x
ZLP-HG LHN LHE M 0007 1976.014 1976.014 0.0 90.0 2 0 x x x x x x x x x x x x x x x
ZLP-HG LHN LHE M 0008 1976.021 1976.230 0.0 270.0 24 3 x x x x x -5 x x x x x x x x x