USGS WPhase Moment Solution

TONGA

13/ 2/15  3: 2:23.00

Epicenter: -19.718 -174.475
MW 5.7

USGS/WPHASE CENTROID MOMENT TENSOR
13/ 2/15  3: 2:23.00
Centroid:  -19.918 -174.263
Depth  80         No. of sta: 15
Moment Tensor;   Scale 10**17 Nm
  Mrr=-2.76       Mtt= 0.24
  Mpp= 2.52       Mrt=-0.13
  Mrp= 4.16       Mtp= 0.73
 Principal axes:
  T  Val=  4.88  Plg=28  Azm=278
  N     =  0.20       7      183
  P     = -5.09      60       79

Best Double Couple:Mo=5.0*10**17
 NP1:Strike= 29 Dip=18 Slip= -63
 NP2:       181     74       -98

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.