USGS WPhase Moment Solution
SANTA CRUZ ISLANDS
13/ 2/11 9:40:23.00 Epicenter: -11.057 166.735 MW 5.7 USGS/WPHASE CENTROID MOMENT TENSOR 13/ 2/11 9:40:23.00 Centroid: -10.757 166.735 Depth 11 No. of sta: 26 Moment Tensor; Scale 10**17 Nm Mrr=-4.05 Mtt= 1.53 Mpp= 2.51 Mrt= 1.10 Mrp=-1.06 Mtp=-2.46 Principal axes: T Val= 4.79 Plg= 9 Azm= 50 N = -0.48 2 319 P = -4.32 79 215 Best Double Couple:Mo=4.6*10**17 NP1:Strike=143 Dip=35 Slip= -85 NP2: 318 55 -93
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.
