USGS WPhase Moment Solution
SOUTHEAST OF LOYALTY ISLANDS
12/03/03 12:19:55 Epicenter: -22.157 170.317 MW 6.6 USGS/WPHASE CENTROID MOMENT TENSOR 12/03/03 12:19:55.00 Centroid: -22.057 170.101 Depth 23 No. of sta: 26 Moment Tensor; Scale 10**18 Nm Mrr=-0.12 Mtt=-3.63 Mpp= 3.74 Mrt= 2.34 Mrp=-2.15 Mtp= 7.52 Principal axes: T Val= 8.47 Plg= 4 Azm=121 N = 0.90 70 18 P = -9.37 18 212 Best Double Couple:Mo=9.0*10**18 NP1:Strike=255 Dip=74 Slip= -10 NP2: 348 80 -163
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.
