USGS Body-Wave Moment Tensor Solution
NORTHERN MID-ATLANTIC RIDGE
12/10/05 00:19:57.14 Epicenter: 17.496 -46.461 MW 5.7 USGS MOMENT TENSOR SOLUTION Depth 3 No. of sta: 17 Moment Tensor; Scale 10**17 Nm Mrr=-1.16 Mtt= 1.57 Mpp=-0.41 Mrt=-1.41 Mrp= 3.52 Mtp=-0.39 Principal axes: T Val= 3.55 Plg=37 Azm=227 N 0.88 16 329 P -4.43 49 78 Best Double Couple:Mo=4.1*10**17 NP1:Strike=151 Dip=84 Slip= -74 NP2: 262 17 -158
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.