USGS WPhase Moment Solution

KEP. MENTAWAI REGION, INDONESIA

12/09/14  4:51:48

Epicenter:  -3.342  100.605
MW 6.2

USGS/WPHASE CENTROID MOMENT TENSOR
12/09/14 04:51:48.00
Centroid:   -3.542  100.504
Depth  23         No. of sta: 18
Moment Tensor;   Scale 10**18 Nm
  Mrr= 0.69       Mtt=-0.07
  Mpp=-0.62       Mrt= 1.72
  Mrp=-1.13       Mtp= 0.39
 Principal axes:
  T  Val=  2.23  Plg=52  Azm= 23
  N     = -0.07      10      127
  P     = -2.16      35      224

Best Double Couple:Mo=2.2*10**18
 NP1:Strike=355 Dip=14 Slip= 139
 NP2:       126     81        80

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.