USGS/SLU Regional Moment Solution
OFF E. COAST OF N. ISLAND, N.Z.
12/10/30 13:12:29.14 Epicenter: -37.949 177.681 MW 4.9 USGS/SLU REGIONAL MOMENT TENSOR Depth 71 No. of sta: 14 Moment Tensor; Scale 10**16 Nm Mrr= 2.55 Mtt=-1.57 Mpp=-0.98 Mrt=-1.78 Mrp= 0.12 Mtp=-1.65 Principal axes: T Val= 3.33 Plg=65 Azm=204 N -0.08 21 60 P -3.26 13 325 Best Double Couple:Mo=3.3*10**16 NP1:Strike=252 Dip=62 Slip= 114 NP2: 29 36 53
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.