Pyroclastic material is another name for a cloud of ash, lava fragments carried through the air, and vapor. Such a flow is usually *very* hot, and moves *rapidly* due to buoyancy provided by the vapors. Pyroclastic flows can extend miles from the volcano, and devastate life and property within their paths.
Considering this, what is a pyroclastic rock?
Pyroclastic rocks are rocks formed by accumulation of material generated by explosive fragmentation of magma and / or previously solid rock, during the course of a volcanic eruption.
How is a tuff formed?
Tuff is an igneous rock that forms from the products of an explosive volcanic eruption. In these eruptions, the volcano blasts rock, ash, magma and other materials from its vent. Instead of being a "layer," a tuff is usually a "lens-shaped" deposit.
How a pyroclastic flow is formed?
Pyroclastic flows contain a high-density mix of hot lava blocks, pumice, ash and volcanic gas. They move at very high speed down volcanic slopes, typically following valleys. "Boiling over" from eruptive vent: during an explosive eruption, material is erupted without forming a high plume and rapidly moves down slope.