USGS/SLU Regional Moment Solution
12/10/06 22:49:36.86 Epicenter: -32.097 -72.290 MW 4.1 USGS/SLU REGIONAL MOMENT TENSOR Depth 18 No. of sta: 12 Moment Tensor; Scale 10**15 Nm Mrr= 1.77 Mtt=-0.09 Mpp=-1.67 Mrt=-0.05 Mrp= 0.76 Mtp= 0.32 Principal axes: T Val= 1.92 Plg=78 Azm=272 N -0.04 2 170 P -1.89 12 80 Best Double Couple:Mo=1.9*10**15 NP1:Strike=352 Dip=57 Slip= 93 NP2: 167 33 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.