USGS WPhase Moment Solution

NORTHERN SUMATRA, INDONESIA

11/ 9/ 5 17:55:13.00

Epicenter:   2.972   97.997
MW 6.7

USGS/WPHASE CENTROID MOMENT TENSOR
11/ 9/ 5 17:55:13.00
Centroid:    2.872   97.997
Depth 100         No. of sta: 35
Moment Tensor;   Scale 10**18 Nm
  Mrr=-2.73       Mtt= 1.58
  Mpp= 1.15       Mrt= 7.65
  Mrp=-8.28       Mtp=-3.26
 Principal axes:
  T  Val= 12.79  Plg=35  Azm= 45
  N     = -1.87       2      137
  P     =-10.93      53      230

Best Double Couple:Mo=1.2*10**19
 NP1:Strike=123 Dip= 9 Slip=-104
 NP2:       317     81       -87

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.