Mw 7.1 Bio-Bio, Chile
updated 28 August 2021

On 22 May 1960 a major earthquake occurred in Bio-Bio, Chile at a depth of 25 km. The seismic event occurred at 10:30:44 UTC and had an estimated moment magnitude (Mw) 7.1.

It was the second major tremor during a series of critical planetary alignments and lunar geometry from 17 to 22 May 1960, which ultimately led to the largest earthquake on record. For more details, see the report of the first earthquake.

Mercury-Sun-Earth         1960-05-17, 15:04:11  237°15'07"
Venus-Sun-Neptune         1960-05-20, 12:29:24  218°27'30"
Mars-Mercury-Uranus       1960-05-21, 15:05:56  141°42'49"
Mercury-Sun-Jupiter       1960-05-22,  8:32:19  266°57'27"

Earth:   Moon-Jupiter     1960-05-17,  4:30:34   45°00'00"
Earth:   Moon-Mars        1960-05-17,  8:09:02   45°00'00"

Earth-Moon-Mars           1960-05-20, 22:49:12    7°53'36"
					
SSGI chart
SSGI depiction of planetary (PG) and lunar (LG) geometry