USGS WPhase Moment Solution

VANUATU

12/ 4/14 22: 5:26.00

Epicenter: -18.997  168.771
MW 6.2

USGS/WPHASE CENTROID MOMENT TENSOR
12/ 4/14 22: 5:26.00
Centroid:  -18.797  168.665
Depth  13         No. of sta: 21
Moment Tensor;   Scale 10**18 Nm
  Mrr=-2.28       Mtt= 2.56
  Mpp=-0.28       Mrt=-0.40
  Mrp= 0.17       Mtp= 1.32
 Principal axes:
  T  Val=  3.10  Plg= 3  Azm=158
  N     = -0.74      10      249
  P     = -2.36      78       52

Best Double Couple:Mo=2.8*10**18
 NP1:Strike=237 Dip=43 Slip=-106
 NP2:        79     49       -75

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.