USGS Body-Wave Moment Tensor Solution
TONGA
13/02/10 09:37:10.51 Epicenter: -18.574 -174.632 MW 5.6 USGS MOMENT TENSOR SOLUTION Depth 122 No. of sta: 10 Moment Tensor; Scale 10**17 Nm Mrr=-1.90 Mtt=-0.56 Mpp= 2.46 Mrt= 1.14 Mrp=-2.22 Mtp= 0.55 Principal axes: T Val= 3.39 Plg=23 Azm= 91 N 0.00 23 351 P -3.40 57 221 Best Double Couple:Mo=3.4*10**17 NP1:Strike=217 Dip=30 Slip= -40 NP2: 343 71 -114
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.
