Global Volcanism Program | Image GVP-01997
A pyroclastic flow travels down the flank of Fugendake in 1991. Pyroclastic flows (specifically the block-and-ash flow type) were created by collapse of a lava dome that began on 24 May. The size of the pyroclastic flows gradually increased and on 3 June the largest flow of the eruption to date swept 3 km down the Mizunashi River valley into Kita-Kamikoba village, killing 43 people and destroying many houses. On 8 June block-and-ash flows traveled 5.5 km to within 50 m of a major highway and destroying an additional 73 houses.
Photo courtesy Willie Scott, 1991 (U.S. Geological Survey).