USGS Body-Wave Moment Tensor Solution
NORTHERN MID-ATLANTIC RIDGE
13/09/05 04:01:36.29 Epicenter: 15.212 -45.219 MW 5.9 USGS MOMENT TENSOR SOLUTION Depth 7 No. of sta: 78 Moment Tensor; Scale 10**18 Nm Mrr=-0.06 Mtt=-0.25 Mpp= 0.31 Mrt=-0.14 Mrp=-0.13 Mtp=-0.96 Principal axes: T Val= 1.03 Plg= 1 Azm= 53 N -0.02 79 148 P -1.01 11 323 Best Double Couple:Mo=1.0*10**18 NP1:Strike= 99 Dip=81 Slip=-173 NP2: 8 83 -9
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.