USGS Body-Wave Moment Tensor Solution
13/02/28 14:05:50.91 Epicenter: 50.924 157.356 MW 6.8 USGS MOMENT TENSOR SOLUTION Depth 46 No. of sta:128 Moment Tensor; Scale 10**19 Nm Mrr= 1.86 Mtt=-0.88 Mpp=-0.98 Mrt= 0.75 Mrp= 0.58 Mtp=-0.77 Principal axes: T Val= 2.10 Plg=76 Azm=329 N -0.16 3 225 P -1.94 14 135 Best Double Couple:Mo=2.0*10**19 NP1:Strike= 47 Dip=59 Slip= 94 NP2: 220 31 84
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.