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Anguilla

Seismic Zone: Low North America

Total Earthquakes

Largest Magnitude

5.2

Seismic Zone

Low

Anguilla is located in North America 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 5.2. With a population of 16,010 and a land area of 91 km², seismic events can have significant implications for infrastructure and public safety.

Seismic Overview

Anguilla is a British Overseas Territory in the northern Lesser Antilles, situated at the junction of the outer carbonate arc and the active volcanic island arc where the North American Plate subducts westward beneath the Caribbean Plate. The island lies immediately north of Saint Martin, approximately 200 kilometres east-northeast of Puerto Rico. Unlike neighbours in the active volcanic arc, Anguilla is built on older Eocene limestone and subdued volcanic hills, placing it on the non-volcanic outer arc of the Lesser Antilles system. The primary seismic source is the [[subduction-zone]] interface to the east-northeast, where convergence occurs at roughly 2 centimetres per year. Secondary sources include the Anegada Passage fault zone to the west, which separates the Greater and Lesser Antilles and is capable of generating moderate to large earthquakes. Seismic hazard is considered moderate — lower than the active volcanic arc islands to the south, but elevated relative to tectonically stable continental regions.

Anguilla's earthquake history reflects proximity to active tectonic structures rather than a record of locally generated destructive events. The great 1843 Guadeloupe earthquake — estimated [[magnitude]] 8.0 — was strongly felt throughout the northern Lesser Antilles including Anguilla, damaging masonry buildings. The 1867 Virgin Islands earthquake (magnitude 7.5), centred in the Anegada Passage, generated a damaging [[tsunami]] that swept coastal communities across the northern arc; Anguilla's low-lying southern shoreline faces meaningful [[tsunami]] exposure from such events. In the instrumental era, the island has registered numerous felt events from the regional subduction system, including M5–6 arc earthquakes and a magnitude 6.3 event in November 2004 near the Virgin Islands.

Anguilla's geology records its position on the carbonate platform of the northern outer arc. The island rises only 65 metres above sea level at its highest point — one of the flattest territories in the Caribbean — reducing landslide risk but amplifying [[tsunami]] inundation potential. Earthquake monitoring is conducted by the University of the West Indies Seismic Research Centre as part of the regional network extending from Trinidad to Puerto Rico. [[tsunami]] preparedness and coastal evacuation planning are the most critical emergency management priorities for this low-lying island, given known hazards from Anegada Passage fault ruptures and Caribbean-wide subduction events.

Recent Earthquakes

Mag	Location	Depth	Time
No recent earthquakes.

Frequently Asked Questions

Anguilla has a low level of seismic activity. Large earthquakes are infrequent but not impossible. A total of 1 earthquakes have been recorded in Anguilla's seismic history.

The largest recorded earthquake in Anguilla had a magnitude of 5.2. Earthquakes of this size can cause significant damage depending on depth, location, and local building standards.

Anguilla 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.

Anguilla is classified in the "Low" seismic zone, located in North America. 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.