USGS Body-Wave Moment Tensor Solution
SANTA CRUZ ISLANDS
13/02/08 23:16:30.56 Epicenter: -11.028 166.722 MW 5.4 USGS MOMENT TENSOR SOLUTION Depth 9 No. of sta: 27 Moment Tensor; Scale 10**17 Nm Mrr=-1.62 Mtt= 0.50 Mpp= 1.12 Mrt= 0.14 Mrp= 0.73 Mtp=-0.90 Principal axes: T Val= 1.84 Plg= 9 Azm=237 N 0.01 17 329 P -1.86 71 120 Best Double Couple:Mo=1.9*10**17 NP1:Strike=161 Dip=56 Slip= -70 NP2: 308 39 -117
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.