Mayotte
Mayotte is located in Africa and has a Low seismic risk classification. A total of 1 earthquakes have been recorded in the country's seismic history. The largest earthquake recorded in the country reached a magnitude of 4.7. With a population of 320,901 and a land area of 374 km², seismic events can have significant implications for infrastructure and public safety.
Seismic Overview
Mayotte is a French overseas department in the Comoros archipelago at the northern entrance to the Mozambique Channel, between Madagascar and the East African coast. The Comoros islands are entirely volcanic in origin, built by a hotspot track that propagated eastward over the past 10 to 20 million years across the East African passive margin. The island chain is not positioned on an active plate boundary in the classic sense, but from late 2018 onward Mayotte became the site of one of the most extraordinary seismic and volcanic events in recent history.
Beginning in May 2018, Mayotte experienced an unprecedented [[seismic-wave]] swarm: over 35,000 events were recorded in the first two years, including a magnitude 5.9 event on 15 May 2018 — the largest earthquake ever recorded in the Comoros region. A large proportion of the [[seismic-wave]] signals were very-long-period tremors traced to a massive submarine volcanic eruption approximately 50 kilometres east-southeast of Mayotte at 3,500 metres depth. The newly formed submarine volcano, informally named "Fani Maoré," erupted over 5 cubic kilometres of lava within 14 months — one of the largest submarine eruptions ever documented — causing Mayotte to subside approximately 13 centimetres and shift 10 centimetres eastward as the magmatic chamber deflated.
The 2018–2019 event transformed understanding of hazard at Mayotte. The island is exposed to continued magmatic [[seismic-wave]] swarms and conventional tectonic seismicity from the diffuse Africa-Somalia plate boundary to the west. Given the low elevation of much of Mayotte and the dense coastal population, both [[tsunami]] risk from submarine mass movements and ongoing volcanic-tectonic hazard remain active concerns. Monitoring has been significantly expanded through the REVOSIMA network using seismometers, ocean-bottom instruments, and GPS receivers.
Recent Earthquakes
| Mag | Location | Time | |
|---|---|---|---|
| No recent earthquakes. | |||
Frequently Asked Questions
Mayotte has a low level of seismic activity. Large earthquakes are infrequent but not impossible. A total of 1 earthquakes have been recorded in Mayotte's seismic history.
The largest recorded earthquake in Mayotte had a magnitude of 4.7. Earthquakes of this size can cause significant damage depending on depth, location, and local building standards.
Mayotte has had 1 recorded earthquakes. This count includes events of all magnitudes detected by seismic monitoring networks. The actual number of earthquakes may be higher, as smaller events can go undetected.
Mayotte is classified in the "Low" seismic zone, located in Africa. Seismic zones indicate the relative level of earthquake hazard based on historical activity, geological conditions, and proximity to tectonic plate boundaries.
During an earthquake, Drop, Cover, and Hold On. Get under a sturdy desk or table, protect your head and neck, and hold on until shaking stops. Move away from windows and heavy objects. After the earthquake, check for injuries and be prepared for aftershocks.
Country earthquake risk is assessed using several factors: proximity to tectonic plate boundaries, historical seismicity (frequency and magnitude of past events), geological conditions, population density in seismic zones, and building code enforcement. QuakeFYI assigns seismic zones from 0 (no risk) to 4 (very high) based on these factors.
A seismic zone is a geographic area classified by the level of earthquake hazard. Zone 0 has negligible risk, Zone 1 has low risk, Zone 2 has moderate risk, Zone 3 has high risk, and Zone 4 has very high risk. These zones are determined by historical earthquake data, tectonic setting, and geological conditions.
Countries along the Pacific Ring of Fire experience the most earthquakes. Japan, Indonesia, Chile, the Philippines, and Iran consistently record the highest seismic activity. The United States (especially Alaska and California), Turkey, and Mexico are also among the most seismically active nations.
Population density amplifies earthquake risk because more people and infrastructure are exposed to potential damage. A magnitude 7.0 earthquake in a densely populated city can cause thousands of casualties, while the same event in an uninhabited area may cause none. Building codes and emergency preparedness greatly reduce risk in populated areas.
Seismic density measures the concentration of earthquake activity relative to a country's land area, expressed as earthquakes per 1,000 square kilometers. A high seismic density indicates frequent earthquake activity per unit area, helping compare seismic risk between countries of different sizes.