USGS Body-Wave Moment Tensor Solution
NEAR ISLANDS, ALEUTIAN ISLANDS
12/11/15 11:22:22.59 Epicenter: 52.474 173.369 MW 5.5 USGS MOMENT TENSOR SOLUTION Depth 26 No. of sta: 47 Moment Tensor; Scale 10**17 Nm Mrr= 1.73 Mtt=-1.96 Mpp= 0.23 Mrt= 0.98 Mrp= 1.05 Mtp=-0.31 Principal axes: T Val= 2.39 Plg=64 Azm=293 N -0.06 20 70 P -2.34 16 166 Best Double Couple:Mo=2.4*10**17 NP1:Strike= 60 Dip=64 Slip= 68 NP2: 283 33 128
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.