USGS Body-Wave Moment Tensor Solution
13/03/07 03:36:46.70 Epicenter: 24.275 121.446 MW 5.5 USGS MOMENT TENSOR SOLUTION Depth 8 No. of sta: 22 Moment Tensor; Scale 10**17 Nm Mrr=-1.80 Mtt= 0.15 Mpp= 1.65 Mrt= 0.65 Mrp= 0.69 Mtp=-0.76 Principal axes: T Val= 2.01 Plg= 6 Azm=250 N 0.20 23 342 P -2.21 67 145 Best Double Couple:Mo=2.1*10**17 NP1:Strike=179 Dip=55 Slip= -62 NP2: 316 43 -124
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.