USGS Body-Wave Moment Tensor Solution
BOUVET ISLAND REGION
12/12/06 21:33:26.30 Epicenter: -54.216 -1.983 MW 5.3 USGS MOMENT TENSOR SOLUTION Depth 4 No. of sta: 18 Moment Tensor; Scale 10**17 Nm Mrr= 0.25 Mtt= 0.47 Mpp=-0.72 Mrt= 0.58 Mrp=-0.19 Mtp=-0.65 Principal axes: T Val= 1.16 Plg=34 Azm= 23 N -0.15 56 209 P -1.01 3 115 Best Double Couple:Mo=1.1*10**17 NP1:Strike=164 Dip=65 Slip= 23 NP2: 64 69 153
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.