USGS Centroid Moment Solution
SANTA CRUZ ISLANDS
12/01/09 04:07:16.59 Epicenter: -10.577 165.178 MW 6.4 USGS CENTROID MOMENT TENSOR 12/01/09 04:07:35.20 Centroid: -9.937 165.034 Depth 41 No. of sta: 28 Moment Tensor; Scale 10**18 Nm Mrr= 1.77 Mtt=-3.59 Mpp= 1.82 Mrt= 0.63 Mrp=-3.16 Mtp=-1.51 Principal axes: T Val= 5.21 Plg=43 Azm= 76 N -1.22 47 251 P -3.99 3 344 Best Double Couple:Mo=4.6*10**18 NP1:Strike=111 Dip=59 Slip= 148 NP2: 219 63 35
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.
