Magnitude 4.9 Moderate Earthquake Recorded Near 76 km NW of Ende, Indonesia

The USGS has confirmed a magnitude 4.9 earthquake with its epicentre 76 km NW of Ende, Indonesia, occurring at 19:03 UTC on Tuesday, August 18, 2026. The event's focal depth — 10.0 km — is a key factor in understanding how this earthquake was experienced at the surface.

Why Depth Matters

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.

Depth is one of the most critical but least discussed parameters of any earthquake. Two earthquakes of identical magnitude can have dramatically different surface effects depending on how deep the rupture originates. Significant damage can occur to vulnerable structures — particularly unreinforced masonry, old adobe buildings, and poorly maintained older construction. Well-engineered modern buildings are designed to withstand this level of shaking with minimal structural impact, though contents may shift and non-structural elements (ceilings, partitions) can be damaged.

Magnitude 4.9: What the Science Says

On the moment magnitude scale, 4.9 represents a moderate earthquake. Moderate earthquakes are felt by virtually everyone near the epicentre. Strong shaking lasting 10–30 seconds can topple unsecured items, crack plaster, and cause poorly anchored objects to fall. Aftershocks are common following moderate events.

A magnitude 4.9 earthquake releases approximately approximately 30,000 tonnes of TNT — comparable to the Hiroshima atomic bomb of energy. For comparison, this exceeds the energy released by most conventional explosive events and is sufficient to shift tectonic stress in measurable ways across a wide region.

Tectonic Setting

Indonesia is located on the Pacific Ring of Fire at the junction of multiple major tectonic plates, including the Indo-Australian, Eurasian, and Pacific plates. With over 17,000 islands along active fault lines and subduction zones, it is among the world's most earthquake-prone nations.

This region's seismic history is an important reminder that earthquake risk is a long-term reality that requires sustained preparedness. Indonesia experiences thousands of earthquakes each year. Major events in recent decades include the 2004 Indian Ocean earthquake and tsunami (M9.1–9.3), the 2006 Yogyakarta earthquake, and the 2018 Sulawesi earthquake and tsunami. The country has invested heavily in tsunami warning infrastructure since 2004.

Practical Safety Information

Regardless of the earthquake's depth or magnitude, standard safety procedures apply. Fasten heavy furniture — bookshelves, water heaters, cabinets — to walls using earthquake straps. Store breakable items on lower shelves and heavy items closest to the floor. These simple steps significantly reduce the risk of injury from falling objects.

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.

BMKG (Badan Meteorologi, Klimatologi, dan Geofisika) operates Indonesia's earthquake and tsunami warning system. Coastal communities should move to higher ground immediately after strong shaking without waiting for an official warning.

Track This Event

All seismic data for this event is being updated in real time as the USGS refines its measurements. Initial magnitude and depth estimates are sometimes revised as more seismograph stations report in — a process that typically completes within hours of the event. Follow updates on our live earthquake map and consider submitting a felt report if you experienced this earthquake directly.

How QuakeWatch Tracks This Event

QuakeWatch sources earthquake data directly from the USGS ComCat (Comprehensive Catalog), which aggregates data contributed by seismic networks worldwide including JMA (Japan), EMSC (Europe and Mediterranean), GFZ (Germany and global), Geoscience Australia, and dozens of national and regional networks. This data is refreshed every 60 seconds, ensuring that new earthquakes appear on our live map within minutes of being processed by the USGS. You can also submit a felt report for this earthquake directly on its detail page.