The flows were entirely restricted to a small fan-shaped zone that flares northward from the summit crater. pyroclastic flow deposits has significant implications with respect to eruption and flow mechanics. One of the most spectacular forms of pyroclastic deposit are the ignimbrites, deposits formed by the high-temperature gas-and-ash mix of a pyroclastic flow event. The following kinds of pyroclastic surge deposits (the general name for all types of low-concentration pyroclastic flows, named on the basis of origin and/or place in sequence), have been indentified: Pyroclastic flows. Ash is considered to be pyroclastic because it is a fine dust made up of volcanic rock. Surges are less dense, they move more quickly and can surmount topography such as hills and ridges. The materials in the flow can be heated from as low as 100 degrees all the way up 800 degrees Fahrenheit. They are incredibly hot and can travel faster than a moving vehicle in some cases. Pyroclastic flows are a mixture of hot gas along with volcanic matter, like ash and rock fragments, she said. Pyroclastic Flow or Nuee Ardente (French: Fiery Cloud) GL-2241. Basically, pyroclastic flows are fluidized masses of gases, rocks, and ash that can exit out of a volcano and travel away from the volcano across the land. In this introductory chapter on pyroclastic rocks we set out the differences between these three basic types of deposit. Pyroclastic flow A pyroclastic flow is a ground-hugging avalanche of hot ash, pumice, rock fragments, and volcanic gas that rushes down the side of a volcano as fast as 100 km/hour or more. Pyroclastic flows are a type of pyroclastic density current consisting of heterogeneous mixtures of hot volcanic particles and gas flowing due to gravity with a higher density than that of air. Pyroclasts of different sizes are classified as volcanic bombs, lapilli, and volcanic ash. https://www.nationalgeographic.org/encyclopedia/pyroclastic-flow The individual rock fragments are known as pyroclasts.Pyroclastic rocks are a type of volcaniclastic deposit. Pyroclastic flows and surges Montserrat, West Indies, 1996 The difference between a pyroclastic flow and a pyroclastic surge is one of degree:- Flows are more dense than surges, consequently they tend to follow topography along predictable paths. The speed of these flows, as well as the extremely high … Pyroclastic rocks (derived from the Greek: πῦρ, meaning fire; and κλαστός, meaning broken) are clastic rocks composed of rock fragments produced by explosive volcanism and erupted as individual particles. We also describe the eruption style and the deposits of different kinds of pyroclastic falls, flows and surges, based on studies of Quaternary volcanoes. 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