USGS Body-Wave Moment Tensor Solution
SANTA CRUZ ISLANDS
13/02/08 15:26:38.95 Epicenter: -10.917 165.977 MW 7.0 USGS MOMENT TENSOR SOLUTION Depth 24 No. of sta: 72 Moment Tensor; Scale 10**19 Nm Mrr=-0.08 Mtt= 0.23 Mpp=-0.16 Mrt= 0.16 Mrp= 0.66 Mtp=-3.29 Principal axes: T Val= 3.37 Plg= 6 Azm=224 N -0.00 78 342 P -3.36 10 133 Best Double Couple:Mo=3.4*10**19 NP1:Strike=178 Dip=87 Slip= -11 NP2: 269 79 -177
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.