USGS WPhase Moment Solution
OFF W COAST OF NORTHERN SUMATRA
12/ 1/10 18:37:1.00 Epicenter: 2.396 93.175 MW 7.2 USGS/WPHASE CENTROID MOMENT TENSOR 12/ 1/10 18:37: 1.00 Centroid: 2.496 92.974 Depth 19 No. of sta: 96 Moment Tensor; Scale 10**19 Nm Mrr= 0.26 Mtt=-2.86 Mpp= 2.60 Mrt= 0.07 Mrp=-1.87 Mtp=-6.29 Principal axes: T Val= 7.11 Plg=13 Azm= 57 N = 0.01 74 206 P = -7.12 7 325 Best Double Couple:Mo=7.1*10**19 NP1:Strike=101 Dip=75 Slip= 176 NP2: 192 86 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.
