Qualibou, also known as the
Soufrière Volcanic Center, is a 3.5 X 5 km-wide caldera on the island of
Saint Lucia
Saint Lucia ( acf, Sent Lisi, french: Sainte-Lucie) is an island country of the West Indies in the eastern Caribbean. The island was previously called Iouanalao and later Hewanorra, names given by the native Arawaks and Caribs, two Amerindian ...
that formed between 32,000 and 39,000 years ago. This eruption also formed the Choiseul Tuff which covers the southeastern portion of the island.
The Pitons are two large lava domes that formed 200 to 300,000 years ago, before the formation of the caldera; ever since then, other domes have filled the caldera floor. There was a
phreatic eruption
A phreatic eruption, also called a phreatic explosion, ultravulcanian eruption or steam-blast eruption, occurs when magma heats ground water or surface water. The extreme temperature of the magma (anywhere from ) causes near-instantaneous evapo ...
in 1766 that deposited ash over a wide area.
Sulfur Springs is an active geothermal area located roughly in the center of the caldera.
In 1990, 1999 and 2000 there were shallow volcanic earthquakes located 6 km ESE of the caldera.
Gallery
Image:Sulphur_Springs_2003.jpg, Sulphur Springs
Image:Petit Piton.JPG, Petit Piton
Image:Day248bdriveq.JPG, Soufrière and the Pitons
References
External links
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Calderas of North America
Geography of Saint Lucia
Volcanoes of Saint Lucia
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