USGS Body-Wave Moment Tensor Solution
OFF EAST COAST OF HONSHU, JAPAN
12/10/01 22:21:45.51 Epicenter: 39.851 143.141 MW 6.0 USGS MOMENT TENSOR SOLUTION Depth 16 No. of sta: 91 Moment Tensor; Scale 10**18 Nm Mrr= 0.65 Mtt=-0.11 Mpp=-0.53 Mrt= 0.60 Mrp= 0.94 Mtp=-0.42 Principal axes: T Val= 1.26 Plg=61 Azm=304 N 0.14 1 212 P -1.40 29 122 Best Double Couple:Mo=1.3*10**18 NP1:Strike= 33 Dip=74 Slip= 91 NP2: 210 16 88
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.