USGS/SLU Regional Moment Solution
ANTIGUA AND BARBUDA REGION
13/04/30 06:56:47.58 Epicenter: 17.517 -62.115 MW 5.3 USGS/SLU REGIONAL MOMENT TENSOR Depth 52 No. of sta: 38 Moment Tensor; Scale 10**16 Nm Mrr= 5.62 Mtt= 1.12 Mpp=-6.74 Mrt=-4.57 Mrp= 5.73 Mtp= 0.80 Principal axes: T Val= 9.75 Plg=59 Azm=213 N -0.17 18 337 P -9.58 24 75 Best Double Couple:Mo=9.7*10**16 NP1:Strike=330 Dip=71 Slip= 71 NP2: 197 27 134
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.