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A magma chamber is a large pool of liquid rock beneath the surface of the Earth. The molten rock, or magma, in such a chamber is less dense than the surrounding country rock, which produces buoyant forces on the magma that tend to drive it upwards. [ 1] If the magma finds a path to the surface, then the result will be a volcanic eruption ...
Mount Mazama ( Tum-sum-ne in the Native American language Klamath [ 5]) is a complex volcano in the western U.S. state of Oregon, in a segment of the Cascade Volcanic Arc and Cascade Range. A volcanic peak once existed, but it collapsed following a major eruption approximately 7,700 years ago, to be replaced by a caldera.
Magmatism. Geological map showing the Gangdese batholith, which is a product of magmatic activity about 100 million years ago. Magmatism is the emplacement of magma within and at the surface of the outer layers of a terrestrial planet, which solidifies as igneous rocks. It does so through magmatic activity or igneous activity, the production ...
Volcanic pipe. Volcanic pipes or volcanic conduits are subterranean geological structures formed by the violent, supersonic eruption of deep-origin volcanoes. They are considered to be a type of diatreme. Volcanic pipes are composed of a deep, narrow cone of solidified magma (described as "carrot-shaped"), and are usually largely composed of ...
Plinian eruption: 1: ash plume; 2: magma conduit; 3: volcanic ash fall; 4: layers of lava and ash; 5: stratum; 6: magma chamber. 1822 artist's impression of the eruption of Mount Vesuvius in 79, depicting what the AD 79 eruption may have looked like, by the English geologist George Julius Poulett Scrope. Lightning is depicted around the rising ...
Magma is produced by melting of the mantle or the crust in various tectonic settings, which on Earth include subduction zones, continental rift zones, [5] mid-ocean ridges and hotspots. Mantle and crustal melts migrate upwards through the crust where they are thought to be stored in magma chambers [6] or trans-crustal crystal-rich mush zones. [7]
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 near-instantaneous evaporation of water to steam, resulting in an explosion of steam ...
Volcanic crater. A volcanic crater is an approximately circular depression in the ground caused by volcanic activity. [ 1] It is typically a bowl-shaped feature containing one or more vents. During volcanic eruptions, molten magma and volcanic gases rise from an underground magma chamber, through a conduit, until they reach the crater's vent ...