Q REPORTS — Peru once again looked to the ground with unease on Thursday when a 7.2 magnitude earthquake shook the Ayacucho region, reigniting a question that resonates throughout South America: why are large earthquakes such a recurring part of its recent history?
In less than two months, Venezuela—first—and Colombia—later—also experienced significant seismic activity.
The new earthquake was centered 35 kilometers north of Coracora, in the province of Parinacochas, and reached a depth of 108 kilometers, according to reports from the Instituto Geofísico del Perú (IGP)—Geophysical Institute of Peru. In the first few hours, no fatalities or serious structural damage were reported, although there were reports of landslides in nearby areas.
The tremor occurred at 1:00 p.m. and was felt in several regions of southern Peru. According to official data from the IGP and the Centro de Operaciones de Emergencia Nacional (COEN)—National Emergency Operations Center, the earthquake was felt in Ayacucho, Arequipa, Cusco, Apurímac, Ica, and also in Lima, where the movement was felt most clearly in tall buildings.
The first images circulating on social media showed dust and landslides on slopes near rural communities, while authorities continued assessing vulnerable areas.
Why Peru is exposed to frequent and large earthquakes
The underlying explanation lies beneath the surface. Peru is located on one of the most active areas on the planet, the Pacific Ring of Fire, a vast band that encircles the Pacific Ocean and concentrates most of the world’s seismic and volcanic activity.
This region accounts for 90% of the world’s earthquakes and more than half of the planet’s active volcanoes.
This geological condition does not mean that every tremor will result in a catastrophe, but it does explain the repetition of episodes of varying intensity throughout the year.
In the case of Peru, the main cause is the Nazca Plate pushing under the South American Plate.
Simply put, a portion of the ocean floor is sliding beneath the continent. This friction accumulates energy over years, and when it is suddenly released, it produces an earthquake.
This dynamic has a technical name: subduction. In everyday language, it is the process by which one tectonic plate descends beneath another. This mechanism explains why the western coast of South America is among the areas with the highest seismic risk on the planet.
The Pacific Ring of Fire concentrates the greatest seismic energy on the planet
Geologist Andrés Folguera, a professor at the University of Buenos Aires (UBA) and a researcher at CONICET, stated that “90% of the Earth’s earthquakes” occur in the Pacific Ring of Fire, in areas where the Pacific Ocean floor subducts beneath the continent.
Folguera explained that, in the case of South America, the Cocos, a geologically young oceanic tectonic plate located beneath the Pacific Ocean off the western coast of Central America and Mexico, Nazca, and Antarctic plates participate in this process along different sections of the Pacific margin. Put more simply, the continent’s coast faces a system of constantly moving plates. This friction is invisible, but it defines the risk map.
Scientist Jorge Rabassa, a geologist with a doctorate in Natural Sciences, reinforced this idea: “All the energy of earthquakes and volcanism is located there. Earthquakes and volcanoes have the same origin: the movement and rupture of geological structures.” This statement summarizes why the problem goes beyond a single event and is part of a structural condition of the region.
The Pacific Ring of Fire is not only notable for its seismic activity but also for harboring the largest number of volcanoes and supervolcanoes on the planet. According to the Smithsonian Global Volcanism Program, this region contains 687 volcanoes that registered activity during the Holocene, representing approximately 57% of the world’s active volcanoes.
The intense tectonic and volcanic activity of the region is also reflected in the monitoring and prevention systems developed by the most exposed countries, such as Japan, Chile, Mexico, and the United States, which have implemented evacuation protocols and strict building codes to reduce risks from extreme events.
The Ring of Fire encircles the Pacific Ocean and runs along the western coast of Latin America, from Chile to Canada, passing through countries such as Colombia, Peru, Ecuador, Panama, Costa Rica, Nicaragua, El Salvador, Guatemala, Mexico, and the United States.
The key to the high seismic and volcanic activity of the Ring of Fire lies in the interaction of numerous tectonic plates. Among the main ones are the Pacific, Nazca, Cocos, Caribbean, North American, South American, Philippine, and Juan de Fuca plates.
In each region, these plates can collide, separate, or slide past each other, generating enormous amounts of stored energy. When the accumulated stress exceeds the resistance of the rocks, it is released suddenly, giving rise to earthquakes and, sometimes, tsunamis if the seismic movement vertically displaces the seabed.
Most of the world’s earthquakes occur near tectonic plate boundaries. The Pacific Ring of Fire is the main stage for this dynamic, as it is where subduction zones, faults, and divergent and convergent plate boundaries are concentrated.
What happened in Ayacucho and what Peruvian authorities said
Thursday’s earthquake reached an intensity of level III-IV in Coracora, according to the IGP (Geophysical Institute of Peru). This scale does not measure the energy released, but rather how the movement is perceived on the surface and what effects it can have on people, homes, and infrastructure. In this case, initial reports described a strong, prolonged event that was felt across a wide area of the country, although damage was limited in the first few hours.
Authorities ruled out the possibility of a tsunami.
This clarification proved crucial because many earthquakes along the Pacific coast generate immediate alarm due to the risk of large waves. On this occasion, the depth of the event and its initial characteristics directed the official assessment toward landslides and localized damage to rural homes.
Hernando Tavera also indicated that Coracora had not reported any loss of life or severe structural damage at the time of the initial assessments. Even so, monitoring teams maintained vigilance in unstable and difficult-to-access areas, where ground movements often occur after the main tremor.
Seismic History in Peru and the Challenge of Living with Risk
Recent history shows that Peru lives with this threat recurrently. In July, the Junín region suffered a series of tremors up to magnitude 5.4 that left five dead, hundreds homeless, and dozens of homes destroyed. Before that, the most devastating earthquake in recent decades was the 2007 Ica earthquake, a magnitude 7.9 quake that caused around 500 deaths and extensive material losses.
This history explains why each new earthquake triggers not only emergency operations but also a public debate about prevention, building quality, and response capacity. Pacific Rim countries like Japan, Chile, Mexico, and Peru itself have developed monitoring systems, building codes, and evacuation protocols to reduce the impact of future events.
Monitoring continues in Ayacucho and the areas near the epicenter, where authorities are working to determine the true extent of the landslides reported this Thursday. Beneath this unstable surface, the interaction of tectonic plates remains active, keeping Peru within one of the geological zones with the highest seismic risk in the world.