The 1784 Peru earthquake occurred at 07:35 local time on 13 May with a moment magnitude of 8.4 and maximum Mercalli intensity of X (Extreme).

[1][2][3][4] The earthquake ruptured about 300 km (190 mi) of the subduction zone in southern Peru with an estimated moment magnitude of 8.4.

[5] In Arequipa, the earthquake killed at least 54 people and injured 500, while the total number of deaths did not exceed 500.

The mainshock produced 4.5 to 5 minutes of shaking that occurred in a south to north direction, and three shocks were felt.

The next phase, described as a swirling motion, lasted 1 minute, causing buildings to collapse and stones dislodged form the middle of walls.