Mw 6.8 Chuquisaca, Bolivia

On 2 April 2018 a strong earthquake occurred at Chuquisaca, Bolivia at a depth of 550 km. The seismic event occurred at 13:40:34 UTC and had an estimated moment magnitude (Mw) 6.8.

It was the last strong earthquake in a series that started on 25 March. No larger seismic activity (Mw 6.6+) occurred until 4 May. These strong earthquakes occurred with a total of eight planetary alignments in just over a week from 23 March to 3 April. The Earth-Mars-Saturn alignment in particular can cause strong seismic activity (Mw 6.6-6.8) within hours of its occurrence. It also happened in May 2017.

Earth-Venus-Uranus        2018-03-29,  0:41:13   27°04'41"
Venus-Sun-Mars            2018-03-30, 15:29:05  236°29'28"
Sun-Mercury-Earth         2018-04-01, 17:46:15  191°41'51"
Earth-Mars-Saturn         2018-04-02, 15:39:02  278°42'12"
Venus-Mercury-Jupiter     2018-04-03, 20:40:52  227°28'59"

Moon-Earth-Uranus         2018-04-01, 17:56:08   27°17'02"
Moon-Earth-Venus          2018-04-02,  2:40:36   32°06'35"
Earth-Moon-Jupiter        2018-04-03, 15:31:38  231°58'31"
          

SSGI depiction of planetary (PG) and lunar (LG) geometry