Friday, Oct 11, 2013
MVO reported that activity at the Soufrière Hills Volcano has remained low over the past week. The dome produced a number of rockfalls and a few volcano-tectonic earthquakes. Volcanic gas emissions were at average levels. [more]
Soufrière Hills volcano (Montserrat): activity summary 27 March-2 April 2013 - small pyroclastic flow on 28 March
Wednesday, Apr 03, 2013
MVO reported that during 22-29 March activity at the Soufrière Hills lava dome was at a low level. ... [more]
Soufriere Hills volcanoSoufrière Hills volcano is a complex stratovolcano that forms the northern half of the small Island of Montserrat in the British Lesser Antilles. After 350 years of quiet, it came back into life in 1995 and started to build a new lava dome. The eruption alternated between less or more intense phases including rapid dome growth with associated powerful vulcanian explosions and large pyroclastic flows from dome collapse.
The eruption, in particular the effects of pyroclastic flows and lahars caused by heavy rains have destroyed a large part of the island, including the capital Plymouth, and the population has been relocated to the northern part of the island and has been fighting, with the help of the UK government, to maintain life on the island.
One of the world's most modern volcano observatories, the MVO, has been installed on the island and while largely unknown prior to 1995, Soufrière Hills volcano now counts as one of the best monitored active volcanoes world-wide.
Montserrat's Soufrière Hills volcano is a typical subduction volcano. Its existence is due to the subduction of the Atlantic under the Caribbean plate.
Its first historic eruption started in 1995 and is still ongoing. During this eruption, the former capital of the island, Plymouth, as well as a large sector of the southern part of the island including its former airport have been devastated by pyroclastic flows and much of it is now buried beneath a thick layer of ash and mud.
The long-term eruption consists in small-to-moderate ash eruptions accompanied by lava-dome growth and pyroclastic flows. Failed eruptions (non eruptive seismic events) had occurred at Soufriere Hills volcano in the 1890's, 1930's, and 1960's.
The complex dominantly andesitic Soufrière Hills volcano occupies the southern half of the island of Montserrat. The summit area consists primarily of a series of lava domes emplaced along an ESE-trending zone. English's Crater, a 1-km-wide crater breached widely to the east, was formed during an eruption about 4000 years ago in which the summit collapsed, producing a large submarine debris avalanche. Block-and-ash flow and surge deposits associated with dome growth predominate in flank deposits at Soufrière Hills.
With the exception of a 17th-century eruption around 1630 AD that produced the Castle Peak lava dome, no historical eruptions were recorded on Montserrat until 1995.