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Cryovolcano. A cryovolcano (sometimes informally referred to as an ice volcano) is a type of volcano that erupts gases and volatile material such as liquid water, ammonia, and hydrocarbons. The erupted material is collectively referred to as cryolava; it originates from a reservoir of subsurface cryomagma. Cryovolcanic eruptions can take many ...
The eruptions originated about 10,000 years ago, during the last ice age, when the summit of Mauna Kea was covered in ice. [60] In 2008, the British Antarctic Survey reported a volcanic eruption under the Antarctica ice sheet 2,200 years ago. It is believed to be that this was the biggest eruption in Antarctica in the last 10,000 years.
Effusive eruptions are most common in basaltic magmas, but they also occur in intermediate and felsic magmas. These eruptions form lava flows and lava domes, each of which vary in shape, length, and width. [2] Deep in the crust, gasses are dissolved into the magma because of high pressures, but upon ascent and eruption, pressure drops rapidly ...
In volcanology, an explosive eruption is a volcanic eruption of the most violent type. A notable example is the 1980 eruption of Mount St. Helens. Such eruptions result when sufficient gas has dissolved under pressure within a viscous magma such that expelled lava violently froths into volcanic ash when pressure is suddenly lowered at the vent.
Phreatic eruption at the summit of Mount St. Helens, Washington, in the spring of 1980. A phreatic eruption, also called a phreatic explosion, ultravulcanian eruption or steam-blast eruption, [1] occurs when magma heats ground water or surface water. The extreme temperature of the magma (anywhere from 500 to 1,170 °C (930 to 2,100 °F)) causes ...
Caldera. A caldera (/ kɔːlˈdɛrə, kæl -/ [1] kawl-DERR-ə, kal-) is a large cauldron -like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the structural integrity of such a chamber, greatly ...
Hawaiian eruption. A Hawaiian eruption is a type of volcanic eruption where lava flows from the vent in a relatively gentle, low level eruption; it is so named because it is characteristic of Hawaiian volcanoes. Typically they are effusive eruptions, with basaltic magmas of low viscosity, low content of gases, and high temperature at the vent.
454 million-year-old volcanic ash between layers of limestone in the catacombs of Peter the Great's Naval Fortress in Estonia near Laagri. This is a remnant of one of the oldest large eruptions preserved. The diameter of the black camera lens cover is 58 mm (2.3 in). Volcanic ash is formed during explosive volcanic eruptions and phreatomagmatic ...