USGS WPhase Moment Solution
NEAR EAST COAST OF HONSHU, JAPAN
11/04/07 14:32:41 Epicenter: 38.252 141.639 MW 7.1 USGS/WPHASE CENTROID MOMENT TENSOR 11/04/07 14:32:41.00 Centroid: 38.252 142.039 Depth 49 No. of sta: 35 Moment Tensor; Scale 10**19 Nm Mrr= 5.92 Mtt=-1.85 Mpp=-4.06 Mrt=-1.43 Mrp=-0.44 Mtp=-1.22 Principal axes: T Val= 6.17 Plg=80 Azm=172 N = -1.48 8 26 P = -4.70 5 295 Best Double Couple:Mo=5.6*10**19 NP1:Strike= 17 Dip=40 Slip= 77 NP2: 213 51 101
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 form 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.