USGS Body-Wave Moment Tensor Solution

ANDREANOF ISLANDS, ALEUTIAN IS.

12/09/26 23:39:57.73

Epicenter:  51.585 -178.231
MW 6.4

USGS MOMENT TENSOR SOLUTION
Depth   8         No. of sta: 128
Moment Tensor;   Scale 10**18 Nm
  Mrr=-1.98       Mtt=-1.33
  Mpp= 3.31       Mrt= 2.19
  Mrp= 0.98       Mtp=-2.19
 Principal axes:
  T  Val=  4.18  Plg= 1  Azm=249
  N        0.31      46      340
  P       -4.49      44      158

Best Double Couple:Mo=4.3*10**18
 NP1:Strike=194 Dip=62 Slip= -35
 NP2:       302     60      -147

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