Volcanic Ash

Volcanic ash consists of fragments of pulverized rock, minerals and volcanic glass, created during volcanic eruptions, less than 2 mm (0.079 in) in diameter. The term volcanic ash is also often loosely used to refer to all explosive eruption products (correctly referred to as tephra), including particles larger than 2mm. Volcanic ash is formed during explosive volcanic eruptions when dissolved gases in magma expand and escape violently into the atmosphere. The force of the escaping gas shatters the magma and propels it into the atmosphere where it solidifies into fragments of volcanic rock and glass. Ash is also produced when magma comes into contact with water during phreatomagmatic eruptions, causing the water to explosively flash to steam leading to shattering of magma. Once in the air, ash is transported by wind up to thousands of kilometers away.

Due to its wide dispersal, ash can have a number of impacts on society, including: human and animal health; disruption to aviation; disruption to critical infrastructure (e.g. electric power supply systems, telecommunications, water and waste-water networks, transportation); primary industries (e.g. agriculture); buildings and structures.

Read more about Volcanic AshFormation, Dispersal, Preparedness, Mitigation and Management

Other articles related to "volcanic, ash, volcanic ash":

Coprates Quadrangle - Layers
... out and often breaking into large pieces these are thought to be hard volcanic rock instead of soft ash deposits ... Because of its closeness to the Tharsis volcanic region, the rock layers may be made of layer after layer of lava flows, probably mixed with deposits of volcanic ash that fell out of the air following big eruptions ... The dark volcanic rock basalt is common on Mars ...
Supervolcano (film) - Plot
... States, burying much of the country under several feet of volcanic ash ... activities do not necessarily indicate an imminent volcanic eruption ... flying back from a conference when their plane flies through the ash cloud, flaming-out the engines and are forced to do a dead stick landing in Cheyenne, Wyoming ...
Volcanic Ash - Preparedness, Mitigation and Management
... and storing sufficient supplies of food and water to last until the ash fall is over and clean-up can begin ... Dust masks can be worn to reduce inhalation of ash and mitigate against any respiratory health affects ... The International Volcanic Ashfall Impacts Working Group of IAVCEI maintains a regularly updated database of impacts and mitigations strategies at http//volcanoes.usgs.gov/ash ...
... Ashstone is a kind of volcanic rock formed from fine volcanic ash ... During an explosive volcanic eruption, fragmentation of the magma can result in the formation of volcanic ash, consisting of sand-sized or smaller particles ... After settling and consolidation this volcanic ash can be considered to be an ashstone a more widely accepted term is tuff ...
Lassen Peak - Early 20th Century Eruptions - Climactic Eruption of May 22, 1915
... eruption (referred to as "the Great Explosion") that blasted volcanic ash, rock fragments, and pumice high into the air ... A huge column of volcanic ash and gas rose more than 30,000 ft (10,000 m) into the air, and was visible from as far as Eureka, 150 mi (240 km) to the west, on the Pacific Coast ... generated a high-speed avalanche of hot ash, pumice, rock fragments, and gas, called a pyroclastic flow, that swept down the side of the volcano, devastating a 3 sq mi (8 km2) area ...

Famous quotes containing the words ash and/or volcanic:

    The last cobwebs
    of fog in the
    black firtrees are flakes
    of white ash in the world’s hearth.
    Denise Levertov (b. 1923)

    Pity the planet, all joy gone
    from this sweet volcanic cone;
    Robert Lowell (1917–1977)