USGS Body-Wave Moment Tensor Solution
ANDREANOF ISLANDS, ALEUTIAN IS.
13/09/14 17:09:04.08 Epicenter: 51.506 -174.592 MW 5.4 USGS MOMENT TENSOR SOLUTION Depth 22 No. of sta: 24 Moment Tensor; Scale 10**17 Nm Mrr= 1.56 Mtt=-1.27 Mpp=-0.29 Mrt= 0.21 Mrp= 0.08 Mtp=-0.36 Principal axes: T Val= 1.58 Plg=86 Azm=337 N -0.17 0 72 P -1.41 4 162 Best Double Couple:Mo=1.5*10**17 NP1:Strike= 71 Dip=49 Slip= 90 NP2: 252 41 91
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.