| Morne Diablotins Volcano |
Morne Diablotins is the highest and largest volcano in Dominica and the second highest mountain in the Eastern Caribbean, measuring 22 km x 18 km at its base and towers to a height of 1421 meters. It dominates the norhthern part of the island. STRUCTURE AND PAST ERUPTIVE ACTIVITYMorne Diablotins is a composite structure composed of several superposed units ranging in age from Pliocene to Pleistocene. The Pliocene rocks from Morne Diablotins are characterized by older submarine volcaniclastic deposits interbedded with limestones and a younger subareial sequence of lava flows and block and ash flows overlain by a thick succession of consolidated block and ash flow deposits and volcaniclastic sandstones and conglomerates. (See photo of cliffside near Gueule Lion) Younger Pleistocene to Recent activity of Morne Diablotins is characterized by Pelean style eruptions with block and ash flows reaching the southwest (Grand Savanne), northwest (Pointe Ronde) and northeast (Londonderry) coasts. This Pelean activity was followed by explosive Plinian activity, with dates ranging from >22,000 to >40,000 years before present. Credits:
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The Pliocene epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present.
The Pleistocene is the epoch from 2.588 million to 12,000 years BP covering the world's recent period of repeated glaciations.
Gravitational and/or explosive collapse of an actively growing dome.
Pelean eruptions are a type of volcanic eruption. They can occur when viscous magma, is involved, and share some similarities with Vulcanian eruptions. The most important characteristics of a Peléan eruption is the presence of a glowing avalanche of hot volcanic ash, a pyroclastic flow. Formation of lava domes is another characteristical feature. Short flows of ash or creation of pumice cones may be observed as well. The 1902 explosion of Mount Pelée is the first described case of a Peléan eruption, and gave it its name.
Open crater eruption, generally with high eruptive column that may collapse to produce flows and surges.
Plinian eruptions are volcanic eruptions marked by their similarity to the eruption of Mount Vesuvius in AD 79 (as described in a letter written by Pliny the Younger), which killed Pliny the Elder. Plinian eruptions are marked by columns of gas and volcanic ash extending high into the stratosphere, a high layer of the atmosphere. The key characteristics are ejection of large amount of pumice and very powerful continuous gas blast eruptions. Short eruptions can end in less than a day, but longer events can take several days to months. The amount of magma erupted can be so large that the top of the volcano may collapse, resulting in a caldera. Plinian eruptions are often accompanied by loud noises, such as those generated by Krakatoa. |
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| Major Settlements Surrounding Morne Diablotins | |
Salisbury, Morne Raquette, Coulibistrie, Colihaut, Dublanc/Bioche, Portsmouth, Bense, Calibishie, Woodfordhill, Wesley. |
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| Recent Activity at Morne Diablotins Volcano | |
NONE |
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| Age Dating from Morne Diablotins (years B.P.) | |
| Location | 14C Date |
| Grand Savanne | >22,200 (Sparks et al 1980) |
| Point Ronde | >46,620 (Lindsay et al 2005) |
| Coulibistrie | >40,000 (Wadge 1989) |
| Fumaroles & Geothermal features associated with Morne Diablotins center. | |
| Morne Turner Fumarole | |
For more information on Morne Diablotins volcano, please visit our FORUM section. |
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| Photographs |
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