[Rockhounds] Pyroclastic Flows May Spread Swift Death on a Cushion of Air

[Kreigh Tomaszewski]

Scientists think they’ve figured out how pyroclastic flows, fast-moving
bringers of death during volcanic events, can travel such incredible
distances and speeds despite the friction between the volcanic material and
the ground.

Pyroclastic flows are searing-hot mixtures of volcanic material and gas
that travel explosively down the slopes of volcanoes, sometimes traversing
tens of miles at hundreds of miles per hour. They’re responsible for some
of the deadliest volcanic events, like the 1883 Krakatoa eruption and the
79 AD Vesuvius eruption that destroyed Pompeii. Though the spewed rocks
should slow due to friction, new research from scientists in New Zealand,
Australia, and the United States seems to show that the flows travel on
cushion of lubricating air.

https://gizmodo.com/pyroclastic-flows-may-spread-swift-death-on-a-cushion-o-1833888985