USGS WPhase Moment Solution

NEAR EAST COAST OF HONSHU, JAPAN

11/03/11  5:46:23

Epicenter:  38.321  142.369
MW 9.0

USGS/WPHASE CENTROID MOMENT TENSOR
11/03/11 05:46:23.00
Centroid:   38.321  142.969
Depth  24         No. of sta:256
Moment Tensor;   Scale 10**22 Nm
  Mrr= 1.82       Mtt=-0.13
  Mpp=-1.69       Mrt= 1.34
  Mrp= 3.17       Mtp=-0.56
 Principal axes:
  T  Val=  3.88  Plg=59  Azm=295
  N     =  0.03       2      201
  P     = -3.92      30      110

Best Double Couple:Mo=3.9*10**22
 NP1:Strike=193 Dip=14 Slip=  81
 NP2:        22     76        92

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 form 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.