USGS WPhase Moment Solution

12/11/12 20:42:14.00

Epicenter:  57.851 -142.906
MW 6.3

USGS/WPHASE CENTROID MOMENT TENSOR
12/11/12 20:42:14.00
Centroid:   57.751 -142.906
Depth  13         No. of sta: 47
Moment Tensor;   Scale 10**18 Nm
  Mrr=-0.24       Mtt=-0.24
  Mpp= 0.48       Mrt=-0.31
  Mrp= 0.67       Mtp= 3.15
 Principal axes:
  T  Val=  3.32  Plg= 4  Azm=311
  N     = -0.11      76      201
  P     = -3.21      12       42

Best Double Couple:Mo=3.3*10**18
 NP1:Strike= 86 Dip=77 Slip=  -5
 NP2:       177     84      -167

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.