Scientists from the Montserrat Volcano Observatory make monitoring measurements in February 1997 as small rockfalls descend the flanks of the summit lava dome. Castle Peak lava dome, constructed during the previous eruption of Soufriere Hills during the 17th century, had collapsed three days prior to the date of this photograph, which was taken from the Tar River Estate house, 2 km NE of the dome. Periodic collapse of the growing lava dome produced pyroclastic flows that in some cases reached to the sea.
A devastating pyroclastic flow on June 25, 1997 sweeps across the lower NE flank of Soufriere Hills volcano on Montserrat. More than two dozen persons within the officially evacuated zone were killed by this pyroclastic flow. The June 25 eruption sent a plume to ~10-km altitude and produced pyroclastic flows and surges that overran both vacated and partly inhabited NE-flank settlements, destroying 100-150 houses in eight villages within the restricted zone. The pyroclastic flow traveled 4.5 km and reached almost to the sea.
Cauliflower-like clouds of ash roil above the surface of a pyroclastic flow sweeping down the eastern flank of the summit lava dome on January 16, 1997. This was the largest single pyroclastic flow of the eruption to date. The pyroclastic flow descended the Tar River valley to the sea, covering the new delta with new material that included blocks 1-2 m in diameter (up to 5-m diameter at the head of the fan).