USGS Body-Wave Moment Tensor Solution
12/10/07 03:14:23.44 Epicenter: 18.551 120.959 MW 5.6 USGS MOMENT TENSOR SOLUTION Depth 37 No. of sta: 35 Moment Tensor; Scale 10**17 Nm Mrr= 2.87 Mtt= 0.60 Mpp=-3.47 Mrt=-0.34 Mrp=-0.81 Mtp=-0.41 Principal axes: T Val= 3.01 Plg=80 Azm=136 N 0.61 6 7 P -3.62 7 276 Best Double Couple:Mo=3.4*10**17 NP1:Strike=359 Dip=38 Slip= 80 NP2: 192 53 98
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.