Dominica has at least 8 potentially active volcanoes. One of these is Morne aux Diables, an isolated composite cone that forms a peninsula at the extreme northern end of the island. Measuring 7 kilometres diameter at its base and rising to a height of 856 meters, Morne aux Diables (creole language name meaning "Mountain of the Devils") is composed of a central complex of Pelean domes from which lithified block and ash flow deposits radiate out in all directions. A prominent fan of these lithified deposits extends southwest from the main dome complex to the Portsmouth-West Cabrits area. This centre is complicated by the presence of five parasitic domes with their flank pyroclastic deposits forming an east-west belt across the southern side of the volcano.
Age dating suggests that the main cone building activity occurred between 1.5 and 1.0 million years ago. Exposed on the volcano's flanks are a number of unconsolidated valley-fill block and ash flow deposits suggesting more recent activity. One of these deposits on the north-east flank of the volcano has been recently dated at ~46,000 years B.P. (before present). Photo of ~26,000-year-old charcoal/wood fragment found in a pyroclastic deposit on flanks of Morne aux Diables.
A large gap exists between the dates obtained for the main edifice building phase of this volcano and the younger valley-fill deposits. This suggests that Morne aux Diables could be: 1) an extinct centre from the age of 2.5 to 1.5 million years that was reactivated during the later Pleistocene; 2) a centre with long repose periods; or 3) could simply be an artefact of the paucity of dates from this volcano.
Although there have been no historical eruptions at Morne aux Diables, there is evidence of potential activity from this centre. This includes the presence of warm, acidic, sulfate-rich springs on the summit of the volcano, hot springs on the coast and the occurrence of shallow earthquake swarms partially located beneath the volcano, the most recent being 2003 and 2009. Other periods of such increased activity were in 2000, 1893 and 1841.
A prominent feature of Morne aux Diables is the Cold Soufriere, an area of cold spring activity in the northwestern crater. This feature is manifested as several clear to milky bubbling pools covering an area of ~25 square meters with temperatures ranging from 23-32 degrees C. An unmistakably strong Hydrogen Sulfide odour is present and vegetation is absent in the immediate area.
View Geological Map of Morne aux Diables (Smith A.L et al: Unpublished data.) Lindsay, J.M; Smith, A.L; Roobol, M.J; & Stasiuk, M.V. 2005. Dominica. In: Lindsay, J.M., Robertson, R.E.A., Shepherd, J.B., & Ali, S. (eds) 2005. Volcanic Hazard Atlas of the Lesser Antilles - Seismic Research Unit, The University of the West Indies, Trinidad and Tobago, W.I, 1-48.
Main Settlements around Morne aux Diables
Portsmouth, Tanetane, Savanne Paille, Guillet, Toucarie, Cottage, Clifton, Capuchin, La Haut, Penville, Vieille Case, Thibaud, Paix Bouche, Dos D'ane, Bornes
Age Dating from Morne aux Diables (years B.P.)
Location | C Date |
Enbas, Vieille Case | 46,740 |
L'autre Bord, Penville | 26,000 |
Recent Activity at Morne aux Diables Volcano
July 10, 2009 earthquake swarm
Beginning the weekend of July 10, residents in the villages on the flanks of Morne aux Diables have been reporting numerous earthquakes which rattle china and on occasions have sent panicked residents into the streets. The quakes are preceded by the sound of an explosion. This swarm continued for more than one year and produced more than 1500 earthquakes.
Fumaroles & Geothermal features associated with Morne aux Diables centre.
Cold Soufriere
Toucarie hot springs (along the seashore)
Balvine Fumaroles
Picard Fumaroles including those at Mamies Sulphur Spring
Prince Rupert's Bay submarine vents
Picard River hot areas
Glosho alkaline hot springs (only alkaline spring in Dominica)