USGS WPhase Moment Solution

VALPARAISO, CHILE

12/10/11 17:22:10.00

Epicenter: -32.867  -70.401
MW 5.5

USGS/WPHASE CENTROID MOMENT TENSOR
12/10/11 17:22:10.00
Centroid:  -32.967  -70.520
Depth 120         No. of sta: 22
Moment Tensor;   Scale 10**17 Nm
  Mrr= 0.05       Mtt=-1.51
  Mpp= 1.46       Mrt=-0.21
  Mrp= 0.26       Mtp= 1.93
 Principal axes:
  T  Val=  2.42  Plg= 3  Azm=295
  N     =  0.07      82      179
  P     = -2.49       6       26

Best Double Couple:Mo=2.5*10**17
 NP1:Strike= 71 Dip=83 Slip=  -2
 NP2:       161     88      -172

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.