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The formation of igneous rock from magma.



the processes of the formation of magma, its subsequent development, displacement, interaction with solid rocks, and solidification.

As one of the most important manifestations of deep-seated activity of the earth, magmatism is directly or indirectly bound up with the development of the earth, its thermal history, and its tectonic evolution. When the nature of tectonics changes there is also a change in the type of magmatism; depending on geological history and confinement to some particular structure of the earth’s crust magmatism is subdivided into geosynclinal, platform, oceanic magmatism, and magmatism of activization areas. Depending on the depth of manifestation (conditions of magma solidification) magmatism is divided into abyssal, hypabyssal, subvolcanic, and surface magmatism. (The last is known as volcanism.) By composition the breakdown is ultrabasic, basic, acid, and alkali. Some experts believe that magmatic processes are especially intensive in the geosynclinal period of the development of folded areas and that certain forms of the manifestation of magmatism are associated with definite stages in the development of a geosyncline. In the modern geological epoch magmatism is especially highly developed in the Pacific geosynclinal belt, the midocean ridges, the rift zones of Africa and the Mediterranean region, and elsewhere. The formation of many different deposits of minerals is associated with magmatism.

References in periodicals archive ?
However, the lateral intraplate magmatism of the crust can also generate characteristics similar to those of island arc granite (Plank, 2005).
Criox belt, which marks the northwestern 'passive' boundary of the Mascarene backarc basin, may be responsible for the generation of Early Devonian magmatism at greater depths compared to the Silurian magmatic activity to the southeast.
Geochemistry and tectonic significance of acid and basic dykes associated with Jalor magmatism, west Raj asthan.
Jurassic magmatism is more extensively distributed in the Eastern and Central Cordillera of the Colombian Andes as well as in the Upper Magdalena Valley.
2012) for the basaltic magmatism occurring in an intraplate, compressive regime.
1981) Gradients in silicic magma chambers: implications for lithospheric magmatism.
For example, if all Phanerozoic volcanic arcs are palaeo-geographically delineated and reconstructed to their present-day locations, then some of them (from different geological time periods) will overlap in areas where subduction was pro longed, or where subduction-related magmatism repeatedly affected the same area of continental crust.
He developed the concept of a mysterious 'Atomgas' that welled up from the interior of the Earth and caused magmatism .
2010, Dioritic intrusions of the Slavkovsky les (Kaiserwald), Western Bohemia: their origin and significance in late Variscan granitoid magmatism, Int.
A renewed period of magmatism affected Madagascar during the Cretaceous period with the emplacement of doleritic dikes and the eruption of basaltic flows along the east coast and in the sedimentary basins of Mahajanga, Morondava and Toliara.