Lesser Antilles Volcanic Arc

Lesser Antilles Volcanic Arc
Name	Lesser Antilles Volcanic Arc
Country	Barbados, Anguilla (British Overseas Territory), Saint Martin, Saint Barthélemy, Saba, Sint Eustatius, Saint Kitts and Nevis, Antigua and Barbuda, Montserrat, Guadeloupe, Dominica, Martinique, Saint Lucia, Saint Vincent and the Grenadines, Grenada
Length km	850
Type	Volcanic arc
Tectonic setting	Caribbean Plate–North American Plate subduction

Lesser Antilles Volcanic Arc

The Lesser Antilles Volcanic Arc is an island chain of active and dormant arc volcanoes formed by the subduction of the North American Plate beneath the Caribbean Plate, producing a north–south trending chain including islands such as Montserrat, Martinique, Dominica, Guadeloupe, Saint Vincent and the Grenadines, and Grenada. The arc influences regional geology, biodiversity, and human settlement patterns across territories administered by United Kingdom, France, Netherlands, and independent states like Dominica (country), Saint Lucia and Antigua and Barbuda. Scientific study involves institutions such as the United States Geological Survey, British Geological Survey, Institut de Physique du Globe de Paris, University of the West Indies, and international programs like the Global Volcanism Program.

Geology and Tectonic Setting

The arc results from the ongoing convergence of the North American Plate and the Caribbean Plate where the western boundary is juxtaposed with the South American Plate in the south near Venezuela. This subduction interface produces a volcanic front above the Wadati–Benioff zone mapped by seismic networks run by USGS, NOAA, Seismic Research Centre (Trinidad and Tobago), and academic groups at Massachusetts Institute of Technology and Imperial College London. Regional structures include the Puerto Rico Trench, the Anegada Passage, and the Mona Passage which influence magmatic segregation observed in studies from Columbia University, University of Oxford, and California Institute of Technology. Plate motion rates constrained by GPS campaigns and modeling by International Seismological Centre and European Space Agency satellites highlight variations tied to the Cuba microplate and the North Andes Plate.

Volcanoes and Island Chain

Major volcanic centers along the chain include stratovolcanoes and complex calderas such as Soufrière Hills, La Grande Soufrière, Mount Pelée, La Soufrière, Mount Pelee (alternate), Kick 'em Jenny, Montserrat Volcano Observatory-monitored edifices, and submarine volcanoes documented by the Monterey Bay Aquarium Research Institute and Woods Hole Oceanographic Institution. Islands bearing volcanoes are part of political entities like Montserrat (island), Martinique (department), Saint Vincent and the Grenadines (state), and Grenada (country), with municipal and national agencies such as Montserrat Volcano Observatory, Seismic Research Centre (Trinidad and Tobago), and French Geological Survey (BRGM) coordinating research. Historical eruptions recorded during colonial eras involve accounts from Spanish Empire, British Empire, First French Republic colonial archives and chronicles in the National Archives (United Kingdom), Bibliothèque nationale de France, and Archivo General de Indias.

Volcanic Activity and Hazards

Eruptions have produced pyroclastic flows, lahars, ashfall, and tsunamis, impacting societies administered by United Kingdom, France, Netherlands (Kingdom of the Netherlands), and independent governments such as Dominica (country), Saint Lucia, and Antigua and Barbuda. Notable crises include the 1995–1997 and 2006–2010 eruptions of Soufrière Hills that prompted evacuations coordinated with United Nations Office for the Coordination of Humanitarian Affairs, Red Cross, UK Ministry of Defence, and relief NGOs like Oxfam. Health and infrastructure impacts involved agencies such as World Health Organization, Pan American Health Organization, Inter-American Development Bank, and national disaster offices like Office of Disaster Management (Montserrat). Hazard mapping and emergency planning draw on historical data from NOAA National Centers for Environmental Information, satellite imagery from Landsat and Sentinel missions, and tsunami models from Intergovernmental Oceanographic Commission.

Petrology and Magma Sources

Petrological investigations show arc magmas range from basaltic to andesitic and rhyolitic compositions with calc-alkaline affinities studied at laboratories in Smithsonian Institution, Geological Survey of Canada, University of Cambridge, University of Bristol, and the Swiss Federal Institute of Technology in Zurich (ETH Zurich). Geochemical tracers such as strontium-neodymium-lead isotopes measured at Scripps Institution of Oceanography, Lamont–Doherty Earth Observatory, and GEOMAR Helmholtz Centre for Ocean Research Kiel indicate slab-derived fluids, mantle wedge metasomatism, and crustal assimilation influenced by lithologies of the Caribbean Large Igneous Province and continental fragments like the South American Shield. Experimental petrology collaborations with Max Planck Institute for Chemistry and University of Hawaiʻi at Mānoa constrain magma storage depths, as imaged by seismic tomography groups at ETH Zurich and University College London.

Geological History and Evolution

The arc’s evolution from the Oligocene–Miocene to the present involved back-arc extension, arc migration, and collision events recorded in stratigraphy archived at institutions like Natural History Museum, London, Muséum national d'Histoire naturelle (Paris), and field studies by geologists from University of Puerto Rico, University of the West Indies, University of Barcelona, and Federal University of Rio de Janeiro. Plio-Pleistocene uplift and sedimentation link to regional paleoclimatic shifts documented by proxies held at Lamont–Doherty Earth Observatory and University of Exeter. Tectonic reconstructions published in journals by American Geophysical Union, Geological Society of America, European Geosciences Union, and Nature Geoscience synthesize paleomagnetic, radiometric, and stratigraphic data.

Monitoring and Risk Management

Monitoring networks are operated by Montserrat Volcano Observatory, Seismic Research Centre (Trinidad and Tobago), Institut de Physique du Globe de Paris, United States Geological Survey, and national civil protection agencies like National Emergency Management Agency (Grenada), Saint Lucia National Emergency Management Organisation, and Office of Disaster Preparedness and Management (Jamaica), with collaboration from universities including University of the West Indies, University of the West of England, and University of Leeds. Risk reduction integrates early warning systems from NOAA, capacity building by United Nations Office for Disaster Risk Reduction, and funding mechanisms through World Bank, Caribbean Development Bank, and bilateral partners such as United Kingdom Foreign, Commonwealth and Development Office and French Directorate-General for Overseas Territories. Community resilience projects involve NGOs including Red Cross, Oxfam, and regional organizations like the Caribbean Disaster Emergency Management Agency.

Category:Volcanic arcs Category:Caribbean geology