Related topics: volcano

Philippine volcano alert lowered, thousands return home

Philippine authorities on Sunday lowered the alert level at Taal Volcano, two weeks after it began spewing ash, steam and rocks, a move that will allow many of the more than 376,000 displaced villagers to return home.

Synchronization of ice cores using volcanic ash layers

Thin, brownish layers of a thickness of about a millimeter or two are sometimes observed in the whitish/transparent ice cores. These brown layers consist of material originating from volcanic eruptions.

Chaos theory provides a way for determining how pollutants travel

Floating air particles following disasters and other largescale geological events can have a lasting impact on life on Earth. Volcanic ash can be projected up to the stratosphere and halt air traffic by lingering in the atmosphere ...

Volcano Raikoke spits ash over Bering Sea

An unexpected and powerful eruption started at Raikoke volcano in the Kuril Islands on 21 June 2019. This image, which was captured on 22 June, shows the brown ash plumes rising high above the dense clouds—drifting eastwards ...

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Volcanic ash

Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than 2 millimetres (0.079 in) in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact with water causing phreatomagmatic eruptions and ejection of entrained particles during steam eruptions causing phreatic eruptions. The violent nature of volcanic eruptions involving steam results in the magma and solid rock surrounding the vent being torn into particles of clay to sand size. Volcanic ash can lead to breathing problems, malfunctions in machinery, and from more severe eruptions, years of global cooling.

Ash deposited on the ground after an eruption is known as ashfall deposit. Significant accumulations of ashfall can lead to the immediate destruction of most of the local ecosystem, as well the collapse of roofs on man-made structures. Over time, ashfall can lead to the creation of fertile soils. Ashfall can also become cemented together to form a solid rock called tuff. Over geologic time, the ejection of large quantities of ash can produce an ash cone.

This text uses material from Wikipedia, licensed under CC BY-SA