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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 ...
Magma that cools slowly within a magma chamber usually ends up forming bodies of plutonic rocks such as gabbro, diorite and granite, depending upon the composition of the magma. Alternatively, if the magma is erupted it forms volcanic rocks such as basalt , andesite and rhyolite (the extrusive equivalents of gabbro, diorite and granite ...
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. The process that forms volcanoes is called volcanism. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and because most of Earth ...
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 ...
Eyjafjallajökull lies 25 km (15 + 1 ⁄ 2 mi) west of another subglacial volcano, Katla, under the Mýrdalsjökull ice cap, which is much more active and known for its powerful subglacial eruptions and its large magma chamber. [33] Each of the eruptions of Eyjafjallajökull in 920, 1612, and 1821–1823 has preceded an eruption of Katla. [34]
A mud volcano or mud dome is a landform created by the eruption of mud or slurries, water and gases. [1][2][3] Several geological processes may cause the formation of mud volcanoes. Mud volcanoes are not true igneous volcanoes as they do not produce lava and are not necessarily driven by magmatic activity.
The Volcanoes portal. A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. The process that forms volcanoes is called volcanism . On Earth, volcanoes are most often found where tectonic plates are diverging or converging ...
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. The volcano is in Klamath County, in the southern Cascades, 60 miles (97 km) north of the Oregon– California border and. Its collapse, due to the eruption ...