Magnitude 5.5 Strong Earthquake Recorded Near 128 km NW of Vallenar, Chile

Seismologists have recorded a magnitude 5.5 earthquake in Chile, with the epicentre located 128 km NW of Vallenar, Chile. The event occurred at 12:22 UTC on Thursday, June 11, 2026 and originated at a depth of 10.0 km.

Seismic Context for Chile

Chile runs along the subduction boundary where the Nazca Plate dives beneath the South American Plate — one of the most seismically active convergent boundaries on the planet. This setting has produced the largest instrumentally recorded earthquake in history.

Chile holds the record for the strongest earthquake ever measured: the 1960 Valdivia earthquake at magnitude 9.5. More recently, the 2010 Maule earthquake (M8.8) and its associated tsunami caused widespread damage. Chileans have developed strong earthquake-preparedness culture over generations.

About This Event

At a focal depth of 10.0 km, this is classified as a shallow earthquake (0–70 km). Shallow events are typically the most damaging: the seismic energy has less distance to travel before reaching the surface, resulting in stronger and more abrupt ground shaking at the epicentre.

In terms of felt effects, a magnitude 5.5 earthquake is typically capable of causing significant damage, particularly to older or poorly built structures. Strong earthquakes cause severe shaking that is difficult to stand through. Duration can reach 30–60 seconds. Widespread damage to ordinary buildings is common; even some well-built structures may sustain damage. Strong ground motion can trigger landslides, liquefaction of saturated soils, and rupturing of underground infrastructure.

Understanding the Magnitude Scale

Earthquake magnitude is measured on a logarithmic scale — meaning each whole-number increase corresponds to roughly 32 times more energy released and approximately 10 times greater ground motion amplitude. A magnitude 5.5 event therefore releases significantly more energy than its number alone might suggest to the casual observer.

The energy released by a magnitude 5.5 earthquake is approximately the equivalent of a large mining explosion or small nuclear device. This is 32 times more energy than a magnitude 4.5 event — the logarithmic nature of the magnitude scale means each whole number increase represents about 32 times more energy.

This magnitude class poses a serious threat to older and poorly constructed buildings. Collapse is possible in the most vulnerable structures. Modern seismically designed buildings are expected to remain standing, though repair or demolition may be necessary after inspection.

What to Do After an Earthquake

Agree on an out-of-area contact that family members can reach if local communications are disrupted. Identify two meeting points: one near your home and one further away. Practise earthquake drills, especially with children and elderly household members.

During and after an earthquake, follow instructions from official civil protection, emergency services, and government authorities. Avoid spreading unverified information on social media. Official channels provide the most reliable information about aftershock risk, evacuation orders, and available assistance.

Staying Informed

SHOA (Servicio Hidrográfico y Oceanográfico de la Armada) manages tsunami warnings for Chile, while SENAPRED coordinates national disaster response. Evacuation routes and tsunami inundation maps are posted in most coastal communities.

QuakeWatch publishes real-time earthquake data sourced from the USGS global catalog — covering every detected seismic event worldwide, 24 hours a day. Visit our live map to see this and all other recent earthquakes, or explore our guide to earthquake magnitude for a deeper understanding of what these numbers mean in practice.

The Science of Seismic Monitoring

Modern earthquake detection relies on a global network of seismographs — sensitive instruments that record ground motion in all three dimensions. When an earthquake occurs, the P-waves (primary, compressional waves) arrive first, followed by the slower S-waves (secondary, shear waves), and finally the surface waves that cause the most felt shaking. By comparing arrival times at multiple stations, scientists can triangulate the earthquake's location and calculate its magnitude within minutes of the event.