USGS WPhase Moment Solution

OFFSHORE EL SALVADOR

12/08/27  4:37:23

Epicenter:  12.279  -88.530
MW 7.3

USGS/WPHASE CENTROID MOMENT TENSOR
12/08/27 04:37:23.00
Centroid:   12.079  -88.530
Depth  11         No. of sta: 77
Moment Tensor;   Scale 10**19 Nm
  Mrr= 5.14       Mtt=-4.54
  Mpp=-0.60       Mrt= 9.36
  Mrp=-5.76       Mtp= 1.55
 Principal axes:
  T  Val= 12.25  Plg=57  Azm= 36
  N     = -0.26       4      299
  P     =-11.99      32      206

Best Double Couple:Mo=1.2*10**20
 NP1:Strike=279 Dip=13 Slip=  69
 NP2:       120     78        95

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.