Mw 7.3 Charleston, South Carolina
updated 31 August 2021

On 1 September 1886 a major earthquake occurred at Charleston, South Carolina. The seismic event occurred at 02:51 UTC and had an estimated moment magnitude (Mw) 7.3. It was an intraplate earthquake in a region not known to produce major earthquakes.

On 26 and 27 August 1886 Mercury lined up heliocentrically with Uranus and Jupiter respectively. Four days later the Moon lined up with both planets within three hours, resulting in a high lunar peak on the 31st reaching index 19. The earthquake occurred at the end of the peak.

Mercury-Sun-Uranus        1886-08-26, 13:01:31  189°14'31"
Mercury-Sun-Jupiter       1886-08-27, 14:26:51  194°40'34"

Earth-Moon-Sun            1886-08-29, 15:44:39  157°46'17"
Earth-Moon-Uranus         1886-08-31, 15:36:23  187°49'17"
Earth-Moon-Jupiter        1886-08-31, 18:39:33  189°42'18"
SSGI chart
SSGI depiction of planetary (PG) and lunar (LG) geometry

earthquake epicentre map
epicentre of the earthquake