Chile has a long history of massive earthquakes , including the 2010 M 8.8 Maule earthquake in central Chile , which ruptured a ~ 400 km long section of the plate boundary immediately south of this 2017 event . The April 24 , 2017 earthquake lies close to where the Juan Fernández Ridge enters the subduction zone , in a section of the plate boundary that ruptured in a M 8.0 earthquake in March 1985 , and previously in the 1906 M 8.2 Valparaiso earthquake ( reported by some to be as large as M 8.6 ) . To the north of the Juan Fernandez Ridge , the subduction zone last ruptured in the M 8.3 Illapel earthquake in September 2015 . This subduction zone also hosted the largest earthquake on record , the 1960 M 9.5 earthquake in southern Chile . Over the century prior to the April 24 , 2017 earthquake , the region within 400 km of this event has hosted 19 M 7 earthquakes . Prior to the April 24 M 6.9 event , the region immediately surrounding this earthquake hosted 9 other events of M 4.5 or larger over the preceding 2 days , including a M 5.9 earthquake on April 23 , 2017 . The 6.9 shock was also preceded by 4 seconds by a M ~ 4 foreshock . Within an hour of the M 6.9 earthquake , 4 aftershocks of M 4.7-5.4 had been located
M 8.3 Illapel earthquake in September 2015
2015 Illapel earthquake
2017 Valparaiso earthquake