USGS/SLU Regional Moment Solution
NEAR COAST OF ANTOFAGASTA, CHILE
12/11/20 01:09:49.28 Epicenter: -21.809 -70.265 MW 4.3 USGS/SLU REGIONAL MOMENT TENSOR Depth 65 No. of sta: 17 Moment Tensor; Scale 10**15 Nm Mrr=-0.05 Mtt=-0.07 Mpp= 0.12 Mrt=-0.26 Mrp=-3.43 Mtp= 0.45 Principal axes: T Val= 3.54 Plg=44 Azm=101 N -0.13 7 4 P -3.40 45 267 Best Double Couple:Mo=3.5*10**15 NP1:Strike=267 Dip= 7 Slip= -7 NP2: 4 89 -97
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.