USGS Body-Wave Moment Tensor Solution
13/01/09 21:46:03.25 Epicenter: -57.050 -141.449 MW 5.5 USGS MOMENT TENSOR SOLUTION Depth 4 No. of sta: 13 Moment Tensor; Scale 10**17 Nm Mrr=-0.49 Mtt= 1.88 Mpp=-1.38 Mrt= 0.51 Mrp= 0.52 Mtp= 1.10 Principal axes: T Val= 2.36 Plg=13 Azm=342 N -0.54 69 215 P -1.82 16 76 Best Double Couple:Mo=2.1*10**17 NP1:Strike=209 Dip=88 Slip=-159 NP2: 118 69 -2
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.