Panic grips southern Chile and Argentina as 7.4 quake sparks tsunami alert, mass evacuations follow

What Happened in Chile and Argentina on May 2?

At 8:58 a.m. local time on May 2, 2025, a powerful 7.4-magnitude earthquake struck the Drake Passage, approximately 218 kilometers south of Puerto Williams in Chile and 219 kilometers from Ushuaia in Argentina. According to the U.S. Geological Survey, the earthquake occurred at a shallow depth of 10 kilometers, a factor that initially heightened the risk of tsunami generation.

Authorities in both Chile and Argentina issued immediate evacuation orders for southern coastal communities, including towns in the Magallanes region and Tierra del Fuego province. Chile’s National Disaster Prevention and Response Service (SENAPRED) confirmed evacuations in Punta Arenas, Puerto Williams, and nearby Chilean Antarctic research stations. Argentina’s civil defence services evacuated residents from Ushuaia and Puerto Almanza as a precaution.

The Pacific Tsunami Warning Center issued a tsunami alert shortly after the quake. The alert remained active for several hours before being lifted after monitoring indicated no significant sea-level disturbances had occurred.

Why Was a Tsunami Alert Issued and Later Cancelled?

The tsunami alert was triggered due to the quake’s magnitude and shallow epicentre, both known to elevate the risk of underwater land displacement capable of producing tsunami waves. Initial models indicated a potential for dangerous sea-level changes, prompting alerts from Chilean naval authorities, Argentina’s emergency services, and international seismic agencies.

However, by the afternoon of May 2, sea-level observation data showed no substantial surges. Chile’s Hydrographic and Oceanographic Service of the Navy (SHOA) and Argentina’s Servicio de Hidrografía Naval assessed real-time measurements from ocean buoys and tide gauges, confirming that the tsunami threat had passed.

SENAPRED lifted evacuation orders later that day, advising residents to remain cautious near coastal zones as minor wave activity could still occur.

How Did the Government and Emergency Services Respond?

The Chilean government, under President Gabriel Boric, mobilised national response teams immediately. Boric, who is originally from Punta Arenas, suspended his official schedule to monitor developments alongside emergency officials.

Chilean Interior Ministry spokespersons said that approximately 2,000 residents and 32 Antarctic personnel were successfully evacuated. Emergency communication systems, including SMS alerts and loudspeaker warnings, were activated across the Magallanes region.

In Argentina, local government units in Tierra del Fuego coordinated closely with national authorities to evacuate at-risk coastal communities. Ushuaia’s mayoral office confirmed no casualties or structural damage but said the event had tested readiness systems effectively.

Was There Any Damage or Casualties?

As of the latest official updates on May 5, no casualties or major infrastructure damage have been reported. Both Chilean and Argentine authorities confirmed that while the tremors were widely felt, especially in southern settlements, there were no immediate reports of injuries or building collapses.

Geological institutes in both countries have stated that aftershocks are possible over the coming days. Chile’s National Seismology Centre continues to monitor seismic activity across the region, advising public caution and adherence to safety advisories.

Where Did the Earthquake Strike and What Is the Geophysical Context?

The earthquake’s epicentre was located in the Drake Passage, a seismically active area where the Scotia and Antarctic tectonic plates converge. This zone, while remote and sparsely populated, is known for frequent seismic activity due to tectonic interactions.

The event was the most powerful recorded in the southern region of South America since the 1949 Tierra del Fuego earthquake, which reached a magnitude of 7.8. Although that earlier event also caused minimal damage due to the area’s low population density, it remains a reference point in regional seismic preparedness.

The May 2 tremor was also noted by international monitoring agencies, including the European-Mediterranean Seismological Centre and the Pacific Tsunami Warning Center, which tracked its propagation in real time.

What Did International Agencies Report?

According to the U.S. Geological Survey, the earthquake’s coordinates placed it firmly within the convergence zone of the Scotia and Antarctic plates. The European-Mediterranean Seismological Centre confirmed the depth and magnitude of the event in its preliminary assessment, while the Pacific Tsunami Warning Center provided model-based evaluations that influenced evacuation orders.

The World Meteorological Organization monitored the potential for broader disruption but reported no requirement for international disaster assistance. International oceanographic and geophysical institutions have begun data analysis to understand the tremor’s implications for tectonic modelling in the region.

How Are Citizens and Local Communities Reacting?

Evacuees across Chile and Argentina have begun returning to their homes following the lifting of the tsunami alert. Local media in Punta Arenas and Ushuaia reported orderly evacuations and high compliance with emergency directives.

In interviews published by regional news outlets, residents expressed relief but noted the unnerving impact of the quake’s force and the tsunami sirens. Civil society groups and schools conducted impromptu earthquake preparedness drills, reinforcing awareness in communities that, while remote, remain at high risk of seismic events.

Officials have credited prior investments in disaster awareness campaigns for the population’s readiness and calm response.

What Happens Next? Are Aftershocks Expected?

Chile’s National Seismology Centre and Argentina’s Instituto Nacional de Prevención Sísmica have indicated that the seismic sequence is not yet over. While no significant aftershocks had occurred as of May 5, experts noted that additional tremors cannot be ruled out.

Authorities are advising continued vigilance, particularly in remote coastal areas and among those living in seismically vulnerable structures. Field teams are currently assessing the structural integrity of schools, health facilities, and bridges in the Magallanes region and Tierra del Fuego province.

Geologists will also analyse tectonic data to evaluate the likelihood of further quakes along the Drake Passage fault line.

How Does This Event Compare to Previous Quakes?

Chile is no stranger to seismic activity and remains one of the most earthquake-prone countries in the world. The 2010 Maule earthquake, which measured 8.8 and resulted in over 500 fatalities, remains the most recent high-impact disaster in Chile’s recent history.

Argentina, particularly its southern provinces, experiences fewer large quakes, but the region has seen increased seismic monitoring in recent years. The 2025 Drake Passage quake, while not catastrophic, was a significant test of binational coordination and the region’s ability to execute large-scale evacuations.

By regional standards, the May 2 event is considered moderate-to-strong in intensity, with its low human impact attributed to the effectiveness of emergency systems and the quake’s remote offshore location.