Seismic Activity in Southern Peru: The 2024 Atiquipa Earthquake and Regional Context

Southern Peru lies along the tectonically active boundary where the Nazca Plate subducts beneath the South American Plate. This subduction zone generates frequent large earthquakes, shaping both the landscape and seismic hazard profile of the coastal region near Atiquipa in the Arequipa department.

On 28 June 2024 at 05:36 UTC, a magnitude 7.2 earthquake struck 10 km west-southwest of Atiquipa at a depth of 24 km. The event occurred within a well-documented seismic gap characterized by recurrent strong shaking. No closer prior events of comparable size have been recorded in the immediate vicinity.

Historical records since 2000 reveal a pattern of significant earthquakes clustered near Atiquipa. A magnitude 7.1 quake occurred 37 km west of Atiquipa on 14 January 2018. Another magnitude 7.1 event took place 16 km west-southwest of the town on 25 September 2013. The largest recent event was the magnitude 8.4 earthquake on 23 June 2001, located 6 km south-southwest of Atico, approximately 99 km from the 2024 epicenter. These events demonstrate persistent strain release along the plate interface at varying depths and distances.

The 24 km depth of the June 2024 mainshock is consistent with interface seismicity typical of this subduction segment. Shallower or deeper events in the same area have produced comparable magnitudes, reflecting the variable locking and slip behavior of the megathrust. Coastal communities in this part of Peru remain exposed to strong ground motion and associated hazards such as landslides and tsunami risk due to the offshore location of many epicenters.

Ongoing monitoring by regional seismic networks continues to track aftershock sequences and background seismicity. The repeated occurrence of magnitude 7+ events within a 30 km radius of Atiquipa underscores the need for sustained preparedness in this segment of the subduction zone.

References

USGS Earthquake Catalog data for events listed (28 Jun 2024 M7.2; 14 Jan 2018 M7.1; 25 Sep 2013 M7.1; 23 Jun 2001 M8.4).