Seismologists have recorded a magnitude 5.5 earthquake in Africa, with the epicentre located 160 km NE of Georgetown, Saint Helena. The event occurred at 06:43 UTC on Saturday, June 20, 2026 and originated at a depth of 10.0 km.
Seismic Context for Africa
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.
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.
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
After an earthquake, expect aftershocks. Check yourself and others for injuries. Inspect your surroundings for hazards before moving — broken glass, gas leaks (smell), downed power lines, and structural damage. If you suspect a gas leak, open windows and evacuate without using electrical switches or open flames.
Keep an earthquake emergency kit accessible at home. It should include at least 72 hours of water (4 litres per person per day), non-perishable food, a first aid kit, torch, battery-powered radio, copies of important documents, and essential medications. Reviewing and restocking this kit annually is strongly recommended.
Staying Informed
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).
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.
Aftershock Probability
After any significant earthquake, the probability of aftershocks follows a well-understood statistical pattern known as the Omori-Utsu Law: aftershock frequency decays roughly as the inverse of elapsed time since the main shock. For a magnitude 5.5 event, there is a meaningful probability of one or more felt aftershocks in the days following the main event. The USGS publishes real-time aftershock forecasts for significant earthquakes, which are updated as the sequence evolves.
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