The Soufrière Hills Volcano on the Caribbean island of Montserrat began erupting in 1995 and the eruption is ongoing.
The activity of the volcano is monitored by the Montserrat Volcano Observatory (MVO), which was set up rapidly in response to the eruption in 1995.
BGS staff managed the MVO from 1997–2008 during which time two Montserratian students achieved PhDs in volcanology and started work at the observatory.
Many research students and scientists from around the world have visited or worked at the MVO.
BGS is now concentrating on volcanic research and continues to work closely with staff from the MVO.
The Soufrière Hills Volcano produces andesite lava which is so thick that it cannot flow, it therefore piles up in the summit crater and builds a lava dome. If parts of the lava dome become unstable they may collapse forming hot, fast-moving avalanches of lava blocks, gas and dust called pyroclastic flows.
A lava dome acts as a cap on pressurised magma inside the volcano. If all or part of the lava dome suddenly collapses it can cause the pressurised magma to explode. Explosions may form large mushroom-shaped plumes reaching up as high as the stratosphere. Volcanic rocks blasted up into these plumes may collapse back onto the flanks of the volcano and form pyroclastic flows.
Volcanic ash – powdered rock – is formed in large quantities during explosions and pyroclastic flows. It can be a serious hazard to human and animal health. Heavy rainfall on the thick deposits of ash around Soufrière Hills Volcano leads to mudflows (lahars).