Historic Earthquakes
Magnitude 6.9 COSTA RICA
1999 August 20 10:02:21 UTC
Dep 25 No. of sta: 57 Moment Tensor; Scale 10**19 Nm Mrr= 1.13 Mtt=-0.74 Mff=-0.40 Mrt= 1.02 Mrf=-0.55 Mtf= 0.55 Principal axes: T Val= 1.63 Plg=67 Azm= 23 N 0.00 4 122 P -1.63 23 214 Best Double Couple:Mo=1.6*10**19 NP1:Strike=312 Dip=23 Slip= 101 NP2: 121 68 86
