USGS Body-Wave Moment Tensor Solution

NEAR ISLANDS, ALEUTIAN ISLANDS

12/09/09 19:23:53.83

Epicenter:  52.822  174.904
MW 5.5

USGS MOMENT TENSOR SOLUTION
Depth 110         No. of sta: 42
Moment Tensor;   Scale 10**17 Nm
  Mrr=-0.43       Mtt=-0.65
  Mpp= 1.08       Mrt=-1.78
  Mrp=-0.67       Mtp= 0.31
 Principal axes:
  T  Val=  1.87  Plg=34  Azm=126
  N        0.47      27      236
  P       -2.34      44      354

Best Double Couple:Mo=2.1*10**17
 NP1:Strike= 58 Dip=85 Slip= -63
 NP2:       158     27      -169

Moment Tensor Solution
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.

Moment Tensor Solution