How did the Montserrat volcano erupt

Soufrière Hills: Pyroclastic currents in the Caribbean

The Soufrière Hills volcano is located on the island of Montserrat. This island is located in the Caribbean and belongs to the Lesser Antilles. Politically, it is a former British crown colony and is still administered by Great Britain today. The tectonic situation in this region is complex, as the oceanic crust of the Atlantic has broken into several small plates. The Lesser Antilles island arc was created by the subduction of the Caribbean plate. The volcanoes in this region are of the Pelean type; they tend to have violent eruptions and relatively long periods of rest between eruptions. Nobody on Montserrat expected a volcanic eruption until the end. The island's capital, Plymouth, is just four and a half kilometers from the summit of the Soufrière Hills volcano.

Pictures from the Soufrière Hills

Pyroclastic flow through the Tuitts Ghaut.

Ash trail after a pyroclastic flow.

Pyroclastic flow in the Gages Valley.

Plymouth was buried under the deposits of pyroclastic flows.

A modern Pompeii was created.

Many houses still seem to be waiting for their residents to return.

The fall of Plymouth

The first swarmquakes occurred in 1992, indicating that magma was rising. On July 18, 1995, the first chimney was blown free by an initial phreatic eruption. A fissure opened along a ridge between two elevations in the summit area of ​​the volcano, and at the end of September a dome of highly viscous lava began to rise up. Further eruptions covered the southern part of the island in particular with ash. When the eruption began, 3,000 residents left the small island and in December Plymouth was evacuated. In March 1996 the lava dome reached a critical size; the steep flanks broke off, and pyroclastic currents arose that found their way through two valleys. On September 17, 1996, the cathedral collapsed. An eruption cloud rose to a height of 14 kilometers, pyroclastic currents destroyed the first houses in the southern part of the island. A new cathedral began to grow. In June 1997 the activity reached its peak. The pyroclastic flows reached further areas. 19 farmers died while working on their fields in the restricted area. The eruptions occurred every 12 hours. In October, pyroclastic currents destroyed the island's capital and covered it with a 1.4 meter thick layer of volcanic deposits.
Shortly afterwards, the volcano calmed down again, but the dome continued to grow. In the following years there were occasional larger outbreaks, but they did not reach the intensity of 1997.
In March 2007, the cathedral's growth stagnated before another eruption occurred in the summer of 2008.

The most recent eruption

The most recent eruptive phase to date began in October 2009. Since then, the Soufrière Hills cathedral has continued to grow slowly. Before the start of this eruptive phase, the volcano was 1050 meters above sea level; due to the renewed growth of the cathedral, its height is currently 1150 meters.
The only safe observation point of the Soufrière Hills volcano is the visitor terrace of the Montserrat Volcanological Observatory. Here you can also get all information about the alarm status and access authorizations for the "security zones". These are blocked during periods of increased activity.
Today Plymouth is like a ghost town. Like a modern Pompeii, the former island capital lies in the "forbidden zone", in the middle of the restricted area and in direct line of the pyroclastic currents that the cathedral occasionally sends out. Many houses were completely destroyed and buried under the deposits of pyroclastic flows and lahars. However, some houses seem almost intact and fully furnished. The residents had to leave their homes within a few hours. The authorities promised to be able to come back soon to at least recover their belongings, but the promise remained. Many drawers and cupboards are well filled. On the shelves, dishes and food are piled up whose use-by date has expired 15 years. Clothes hang in the closets and a half-packed suitcase lies on a bed. Even a piggy bank with coins was left behind.
A good 4,000 people lived in the former island capital. Many of them left their homeland forever.

As of 2010

© All rights reserved. created by Marc Szeglat.