The USGS has confirmed a magnitude 4.8 earthquake with its epicentre southern Mid-Atlantic Ridge, occurring at 19:24 UTC on Thursday, July 16, 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 4.8: What the Science Says
On the moment magnitude scale, 4.8 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 4.8 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
Africa is generally considered a stable continental landmass with lower seismic activity than plate boundary regions. However, the East African Rift System — stretching from the Afar Triangle through Ethiopia, Kenya, Tanzania, and Mozambique — generates significant earthquakes as the continent slowly tears apart.
This region's seismic history is an important reminder that earthquake risk is a long-term reality that requires sustained preparedness. North Africa, particularly Morocco, Algeria, and the Mediterranean coast, faces moderate to high seismic hazard from the African-Eurasian collision. The 2003 Boumerdès earthquake in Algeria (M6.8, ~2,200 deaths) and the 2023 Al Haouz earthquake in Morocco (M6.8, ~3,000 deaths) demonstrated the region's vulnerability.
Practical Safety Information
Regardless of the earthquake's depth or magnitude, standard safety procedures apply. The internationally recommended action during earthquake shaking is Drop, Cover, and Hold On: drop to your hands and knees, take cover under a sturdy table or desk (or protect your head with your arms if no shelter is available), and hold on until shaking stops. Do not run outside during shaking — most injuries occur when people attempt to move.
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.
National civil protection agencies in affected countries coordinate responses, often with support from international organisations including the UN Office for the Coordination of Humanitarian Affairs (OCHA).
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.
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.
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