USGS WPhase Moment Solution

VANUATU

13/ 2/28  3: 9:44.00

Epicenter: -17.770  167.340
MW 5.9

USGS/WPHASE CENTROID MOMENT TENSOR
13/ 2/28  3: 9:44.00
Centroid:  -17.570  167.130
Depth  25         No. of sta: 33
Moment Tensor;   Scale 10**17 Nm
  Mrr= 4.93       Mtt=-1.90
  Mpp=-3.03       Mrt=-1.57
  Mrp=-5.45       Mtp= 4.04
 Principal axes:
  T  Val=  8.74  Plg=55  Azm=122
  N     = -1.24      29      338
  P     = -7.50      17      238

Best Double Couple:Mo=8.2*10**17
 NP1:Strike=292 Dip=38 Slip=  37
 NP2:       171     68       122

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.