USGS Body-Wave Moment Tensor Solution

TONGA

13/05/11 20:46:57.93

Epicenter: -17.946 -175.096
MW 6.4

USGS MOMENT TENSOR SOLUTION
Depth 238         No. of sta: 98
Moment Tensor;   Scale 10**18 Nm
  Mrr=-3.66       Mtt= 2.19
  Mpp= 1.48       Mrt=-0.36
  Mrp=-2.77       Mtp= 1.53
 Principal axes:
  T  Val=  4.01  Plg=17  Azm=133
  N        0.88      17       37
  P       -4.89      66      264

Best Double Couple:Mo=4.5*10**18
 NP1:Strike=247 Dip=32 Slip= -56
 NP2:        29     64      -109

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