USGS/SLU Regional Moment Solution
13/02/04 04:29:46.79 Epicenter: 43.681 16.402 MW 4.0 USGS/SLU REGIONAL MOMENT TENSOR Depth 8 No. of sta: 14 Moment Tensor; Scale 10**15 Nm Mrr= 1.22 Mtt=-1.16 Mpp=-0.06 Mrt=-0.16 Mrp=-0.32 Mtp= 0.41 Principal axes: T Val= 1.32 Plg=74 Azm=112 N -0.02 16 288 P -1.30 1 18 Best Double Couple:Mo=1.3*10**15 NP1:Strike=124 Dip=46 Slip= 113 NP2: 273 48 68
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.