USGS Body-Wave Moment Tensor Solution
11/04/07 13:11:24.02 Epicenter: 17.412 -94.007 MW 6.6 USGS MOMENT TENSOR SOLUTION Depth 155 No. of sta: 29 Moment Tensor; Scale 10**19 Nm Mrr=-0.46 Mtt=-0.12 Mpp= 0.58 Mrt= 0.75 Mrp=-0.58 Mtp=-0.30 Principal axes: T Val= 1.14 Plg=29 Azm= 58 N -0.04 19 317 P -1.10 54 197 Best Double Couple:Mo=1.1*10**19 NP1:Strike=189 Dip=24 Slip= -35 NP2: 312 77 -110
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 form 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.