USGS WPhase Moment Solution
SANTA CRUZ ISLANDS
12/ 9/ 5 13: 9:9.00 Epicenter: -12.504 166.411 MW 6.0 USGS/WPHASE CENTROID MOMENT TENSOR 12/ 9/ 5 13: 9: 9.00 Centroid: -12.404 166.104 Depth 21 No. of sta: 39 Moment Tensor; Scale 10**18 Nm Mrr=-1.02 Mtt= 0.21 Mpp= 0.81 Mrt=-0.68 Mrp=-0.45 Mtp=-0.54 Principal axes: T Val= 1.13 Plg= 1 Azm= 60 N = 0.36 30 151 P = -1.50 59 327 Best Double Couple:Mo=1.4*10**18 NP1:Strike=123 Dip=51 Slip=-130 NP2: 357 54 -51
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.
