USGS WPhase Moment Solution

SANTA CRUZ ISLANDS REGION

13/ 2/12 23:32:36.00

Epicenter: -11.003  164.217
MW 5.5

USGS/WPHASE CENTROID MOMENT TENSOR
13/ 2/12 23:32:36.00
Centroid:  -10.803  164.013
Depth  11         No. of sta: 18
Moment Tensor;   Scale 10**17 Nm
  Mrr=-1.09       Mtt=-0.00
  Mpp= 1.09       Mrt=-1.69
  Mrp=-0.69       Mtp= 1.39
 Principal axes:
  T  Val=  2.70  Plg=23  Azm=131
  N     = -0.35      28      234
  P     = -2.35      51        8

Best Double Couple:Mo=2.5*10**17
 NP1:Strike=179 Dip=34 Slip=-150
 NP2:        64     74       -59

Moment Tensor Solution
The figure above shows a visual representation of the style of faulting (focal mechanism) derived from the estimated moment tensor. Shaded areas show quadrants of the focal sphere in which the P-wave first-motions are away from the source, and unshaded areas show quadrants in which the P-wave first-motions are toward the source. The dots represent the axis of maximum compressional strain (in black, called the "P-axis") and the axis of maximum extensional strain (in white, called the "T-axis") resulting from the earthquake.

Moment Tensor Solution

Details on the W-phase inversion algorithm.