USGS Body-Wave Moment Tensor Solution
12/07/01 22:01:27.77 Epicenter: 34.508 59.893 MW 5.1 USGS MOMENT TENSOR SOLUTION Depth 13 No. of sta: 19 Moment Tensor; Scale 10**16 Nm Mrr= 4.63 Mtt=-1.77 Mpp=-2.86 Mrt=-1.41 Mrp= 1.12 Mtp= 1.80 Principal axes: T Val= 5.00 Plg=78 Azm=209 N -0.47 4 321 P -4.52 11 52 Best Double Couple:Mo=4.8*10**16 NP1:Strike=318 Dip=56 Slip= 85 NP2: 148 34 98
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.