USGS Body-Wave Moment Tensor Solution
TONGA
12/04/28 10:08:07.68 Epicenter: -18.657 -174.704 MW 6.7 USGS MOMENT TENSOR SOLUTION Depth 132 No. of sta: 95 Moment Tensor; Scale 10**19 Nm Mrr=-0.88 Mtt= 0.90 Mpp=-0.02 Mrt= 0.85 Mrp= 0.50 Mtp= 0.19 Principal axes: T Val= 1.34 Plg=23 Azm=343 N -0.00 10 248 P -1.34 64 137 Best Double Couple:Mo=1.3*10**19 NP1:Strike=245 Dip=69 Slip=-101 NP2: 93 23 -64
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.
