Real-time coverage of earthquake event — 29 km ENE of Calama, Chile — Pandita Data.
🌍 OPEN LIVE 3D EARTHQUAKE MAPA magnitude 6.9 earthquake struck 29 km northeast of Calama, Chile, at 21:52 UTC on May 25, 2026, at a depth of 109 km beneath the Earth's surface. The US Geological Survey issued a GREEN PAGER alert—indicating low potential for damage—and no tsunami warning was issued. Although 56 people reported feeling the tremor across the region, the intermediate depth of this rupture significantly reduced ground shaking intensity at the surface, limiting structural damage risk in the sparsely populated Atacama Desert.
The Calama region sits within the Atacama Subduction Zone, where the Nazca Plate descends beneath the South American Plate at a rate of approximately 7 cm per year. This convergent boundary has generated some of South America's most powerful earthquakes. The 1995 Antofagasta earthquake (M8.0) occurred just 200 km south of this event. The intermediate depth (109 km) indicates this rupture initiated within the subducting Nazca slab itself—a process called intraslab seismicity—rather than at the plate interface. These deep-focus earthquakes occur as cold, brittle oceanic lithosphere fractures under extreme pressure within the mantle.
This M6.9 earthquake released approximately 708 megatons of energy—equivalent to 177 Hiroshima-class bombs. The rupture propagated through cold, dense oceanic crust now 109 km into the mantle. Intermediate-depth subduction zone earthquakes typically produce less surface ground motion than shallow crustal events of the same magnitude because seismic waves attenuate over greater distances through the surrounding rock. Energy release was concentrated at depth, reducing the shaking experienced in Calama and nearby settlements.
Deep earthquakes (70–700 km) occur in cold, brittle subducting slabs undergoing phase transitions. Ground motion diminishes with distance—at 109 km depth, seismic energy dissipates through 100+ km of rock before reaching surface communities. A M6.9 at 109 km typically causes light-to-moderate shaking in nearby towns; the same magnitude at 15 km (shallow crustal) would cause severe ground motion and widespread structural damage.
Calama, with approximately 150,000 residents, is the largest city in the region and serves as a hub for copper mining operations in the Atacama. The surrounding area is sparsely populated due to extreme aridity. No significant damage reports have been confirmed. Historical seismic hazard maps classify this zone as moderate-risk due to regular intermediate-depth activity. The USGS PAGER system assigned a GREEN alert because the rupture depth and low population density in the epicentral area minimized casualty and economic loss potential.
Explore live earthquake data and real-time plate motion at Pandita Data's 3D earthquake simulator to understand how subduction zone ruptures propagate and interact with crustal structure across the Atacama region.
FAQ::[{"q":"What caused this earthquake?","a":"Intraslab rupture within the subducting Nazca Plate at 109 km depth as cold oceanic lithosphere fractures under mantle pressure in the Atacama Subduction Zone."},{"q":"Is a tsunami risk associated