USGS Body-Wave Moment Tensor Solution
FOX ISLANDS, ALEUTIAN ISLANDS
11/09/02 10:55:55.54 Epicenter: 52.196 -171.656 MW 6.8 USGS MOMENT TENSOR SOLUTION Depth 34 No. of sta: 103 Moment Tensor; Scale 10**19 Nm Mrr= 0.86 Mtt= 0.75 Mpp=-1.60 Mrt= 0.52 Mrp= 0.84 Mtp= 0.57 Principal axes: T Val= 1.63 Plg=47 Azm=334 N 0.29 39 184 P -1.92 15 81 Best Double Couple:Mo=1.8*10**19 NP1:Strike=131 Dip=46 Slip= 28 NP2: 20 71 1320
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.