USGS Body-Wave Moment Tensor Solution
13/05/12 10:54:50.75 Epicenter: 26.788 57.748 MW 5.5 USGS MOMENT TENSOR SOLUTION Depth 14 No. of sta: 66 Moment Tensor; Scale 10**17 Nm Mrr= 0.01 Mtt=-0.74 Mpp= 0.73 Mrt= 0.49 Mrp= 0.30 Mtp= 1.80 Principal axes: T Val= 2.07 Plg=14 Azm=305 N -0.09 74 97 P -1.98 7 213 Best Double Couple:Mo=2.0*10**17 NP1:Strike=348 Dip=75 Slip= 175 NP2: 80 85 15
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.