USGS Body-Wave Moment Tensor Solution
CENTRAL EAST PACIFIC RISE
12/09/06 23:33:06.68 Epicenter: -4.555 -105.864 MW 5.7 USGS MOMENT TENSOR SOLUTION Depth 8 No. of sta: 25 Moment Tensor; Scale 10**17 Nm Mrr= 0.62 Mtt=-0.43 Mpp=-0.19 Mrt= 0.49 Mrp= 0.58 Mtp= 4.50 Principal axes: T Val= 4.35 Plg=11 Azm=314 N 0.46 79 137 P -4.81 1 44 Best Double Couple:Mo=4.6*10**17 NP1:Strike= 90 Dip=82 Slip= 8 NP2: 359 82 171
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.