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Related to pyroclastic: Pyroclastic rocks


Composed chiefly of rock fragments or particles of volcanic origin, such as pumice, obsidian, or volcanic ash.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Geological Science) (of rocks) formed from the solid fragments ejected during a volcanic eruption
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌpaɪ rəˈklæs tɪk)

composed chiefly of volcanic rock fragments, as agglomerate or tuff.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


adj (Geol) rockspyroklastisch; pyroclastic flowpyroklastischer Strom
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Phivolcs reminded the public to keep out of the six-kilometer permanent danger zone around the volcano and the seven-kilometer extended danger zone in the south-southwest to east-northeast sector, as sudden explosions, lava collapses, pyroclastic density and ashfall could still occur and threaten areas in the upper to middle slopes.
'Historically, Clark has pyroclastic flows and lahar.
The agency reiterated its warning to the public that sudden explosions, lava collapses, pyroclastic density currents and ashfalls could still occur and threaten villages along the slopes of the volcano.
It is classified as a complex stratovolcano because its eruptions consist of explosive eruptions as well as pyroclastic flows.
Quoting Japan's Meteorological Agency, NHK World reported that people have been advised to seek shelter and be on alert for volcanic rocks and pyroclastic flows.
"Phivolcs reminds the public that sudden explosions, lava collapses, pyroclastic density currents or PDCs (pyroclastic density currents) and ashfall can still occur and threaten areas in the upper to middle slopes of Mayon," the bureau said.
It also issued warnings against large falling volcanic rocks within 3 kilometers of the crater and pyroclastic flows in areas within about 2 km of the crater.
Rescue workers have been searching frantically for survivors and victims in the lava-ravaged landscape left by the eruptions, which showered volcanic ash over nearby towns and spewed pyroclastic flows throughout the area.
The Volcan de Fuego, Spanish for "Volcano of Fire," erupted Sunday and released a 8-km stream of lava, a pyroclastic cloud and ash that fell over nearby Guatemala City, the country's capital.
Dramatic video showed a fast-moving lahar, or flow of pyroclastic material and slurry, slamming into and partly destroying a bridge on a road between Sacatepequez and Escuintla.
The charred bodies of victims laid on the steaming, ashen remnants of a pyroclastic flow as rescuers attended to badly injured victims in the aftermath of the eruption.
Volcanoes in the Lassen, Shasta and Long Valley areas are capable of producing pyroclastic flows or surges when they do erupt -- fast-moving flows of hot ash, rock and gas sweeping down the sides of mountains, of the type that killed 57 people when Mount St.