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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. The volcano is in Klamath County, in the southern Cascades, 60 miles (97 km) north of the Oregon– California border. Its collapse, due to the eruption of ...
Changes in chemical and physical properties causes the magma to become concentrated in chromite. When this happens the liquidus becomes free from any other phases. Therefore, chromite is the only mineral to crystallize in the melt thus, accumulating in monomineralic layers on the floor of the magma chamber.
Molten rock (either magma or lava) near the atmosphere releases high-temperature volcanic gas (>400 °C). In explosive volcanic eruptions, the sudden release of gases from magma may cause rapid movements of the molten rock. When the magma encounters water, seawater, lake water or groundwater, it can be rapidly fragmented.
In this sort of eruption, the rising magma is quickly cooled on contact with ground or surface water. Stresses within the "quenched" magma cause fragmentation into five dominant pyroclast shape-types: (1) blocky and equant; (2) vesicular and irregular with smooth surfaces; (3) moss-like and convoluted; (4) spherical or drop-like; and (5) plate ...
These more detailed studies showed the southern portion of Kamaʻehuakanaloa's summit had collapsed, a result of a swarm of earthquakes and the rapid withdrawal of magma from the volcano. A crater 0.6 mi (1 km) across and 330 yd (300 m) deep formed out of the rubble. The event involved the movement of 100 million cubic meters of volcanic material
Dacite eruptions in the Lassen area typically begin with steam explosions caused by the interaction of rising magma with ground water. [4] When dacite magma charged with volcanic gases reaches the surface, it erupts explosively, usually as a vertical column of gas and ash that can rise several miles into the atmosphere. Heavy fallback of hot ...
In geology, igneous differentiation, or magmatic differentiation, is an umbrella term for the various processes by which magmas undergo bulk chemical change during the partial melting process, cooling, emplacement, or eruption. The sequence of (usually increasingly silicic) magmas produced by igneous differentiation is known as a magma series.