USGS WPhase Moment Solution

HOKKAIDO, JAPAN REGION

13/ 2/ 2 14:17:34.00

Epicenter:  42.811  143.078
MW 6.9

USGS/WPHASE CENTROID MOMENT TENSOR
13/ 2/ 2 14:17:34.00
Centroid:   42.811  143.214
Depth 110         No. of sta: 78
Moment Tensor;   Scale 10**19 Nm
  Mrr=-0.40       Mtt= 0.52
  Mpp=-0.11       Mrt= 2.85
  Mrp=-0.15       Mtp= 0.15
 Principal axes:
  T  Val=  2.94  Plg=40  Azm=359
  N     = -0.10       3       92
  P     = -2.84      49      186

Best Double Couple:Mo=2.9*10**19
 NP1:Strike= 54 Dip= 6 Slip=-129
 NP2:       273     85       -86

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.