USGS Body-Wave Moment Tensor Solution

OFF W. COAST OF N. ISLAND, N.Z.

12/07/03 10:36:15.97

Epicenter: -39.976  173.693
MW 6.3

USGS MOMENT TENSOR SOLUTION
Depth 229         No. of sta: 25
Moment Tensor;   Scale 10**18 Nm
  Mrr= 0.08       Mtt= 0.94
  Mpp=-1.02       Mrt= 2.74
  Mrp=-2.08       Mtp=-0.55
 Principal axes:
  T  Val=  3.95  Plg=41  Azm= 28
  N       -0.79      15      131
  P       -3.17      45      236

Best Double Couple:Mo=3.6*10**18
 NP1:Strike= 49 Dip=15 Slip=-172
 NP2:       311     88       -75

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