USGS Body-Wave Moment Tensor Solution
12/07/08 11:33:02.54 Epicenter: 45.495 151.354 MW 5.8 USGS MOMENT TENSOR SOLUTION Depth 20 No. of sta: 98 Moment Tensor; Scale 10**17 Nm Mrr= 4.63 Mtt=-1.19 Mpp=-3.44 Mrt= 2.48 Mrp= 3.96 Mtp=-1.72 Principal axes: T Val= 6.62 Plg=67 Azm=304 N -0.27 2 210 P -6.35 23 120 Best Double Couple:Mo=6.5*10**17 NP1:Strike= 31 Dip=68 Slip= 92 NP2: 206 22 86
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.