USGS Body-Wave Moment Tensor Solution
SANTA CRUZ ISLANDS REGION
13/02/08 09:09:01.59 Epicenter: -10.914 164.741 MW 5.5 USGS MOMENT TENSOR SOLUTION Depth 6 No. of sta: 51 Moment Tensor; Scale 10**17 Nm Mrr=-1.65 Mtt= 0.80 Mpp= 0.85 Mrt=-0.19 Mrp= 0.98 Mtp= 0.90 Principal axes: T Val= 1.84 Plg=10 Azm=310 N 0.24 21 216 P -2.07 66 64 Best Double Couple:Mo=2.0*10**17 NP1:Strike= 64 Dip=39 Slip= -56 NP2: 202 59 -115
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.