pyroclastic rock
Quick Summary
Pyroclastic rock refers to fragmented volcanic material ejected during an eruption, classified by size from dust to bombs. These materials are formed when expanding gases shred magma into pieces. Pyroclastic flows are fast-moving, ground-hugging clouds of hot rock fragments, gases, and air, capable of reaching speeds over 100 km/hour and causing immense destruction. They are distinct from lava flows, which are molten rock that moves slowly and solidifies into rock. Ignimbrites and nuées ardentes are types of deposits left by pyroclastic flows.1
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rockClassification by grain or crystal sizePyroclastic rocks are those formed from clastic (from the Greek word for broken) material ejected from volcanoes. Blocks are fragments broken from solid rock, while bombs are molten when ejected.
Read MorePyroclastic rocks are those formed from clastic (from the Greek word for broken) material ejected from volcanoes. Blocks are fragments broken from solid rock, while bombs are molten when ejected.
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igneous rock…magma of various sizes (pyroclastic materials), which often are blown through the atmosphere and blanket Earth’s surface upon settling. The coarser pyroclastic materials accumulate around the erupting volcano, but the finest pyroclasts can be found as thin layers located hundreds of kilometres from the opening. Most lava flows do…
Read More…magma of various sizes (pyroclastic materials), which often are blown through the atmosphere and blanket Earth’s surface upon settling. The coarser pyroclastic materials accumulate around the erupting volcano, but the finest pyroclasts can be found as thin layers located hundreds of kilometres from the opening. Most lava flows do…
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