What is felsic magma?
Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. Felsic magma or lava is higher in viscosity than mafic magma/lava. Felsic rocks are usually light in color and have specific gravities less than 3.
Whats the definition of felsic?
Definition of felsic : consisting of or chiefly consisting of feldspar or feldspathoid quartz.
What are mafic and felsic magma types?
Mafic lava creates basalt while felsic lava produces andesitic and rhyolite rocks. 5. Either in describing rocks or lava, mafic means that the lava or rock has less silica while felsic implies that the lava or rock has the most silica. 6.
What is felsic and mafic?
In a widely accepted silica-content classification scheme, rocks with more than 65 percent silica are called felsic; those with between 55 and 65 percent silica are intermediate; those with between 45 and 55 percent silica are mafic; and those with less than 45 percent are ultramafic.
How is felsic magma formed?
It has been suggested that felsic magmas found at subduction-zone volcanoes are produced by mechanisms including fractional crystallization with or without crustal assimilation8, partial melting of the crust9,10, and partial melting of metasomatised silica-excess pyroxenite mantle11,12.
What is mafic magma?
Describes magma that contains lower amounts of silica and is generally less viscous and less gas-rich than silicic magma. Tends to erupt effusively, as lava flows. Includes andesites (57-63 percent SiO2), basaltic andesites (53-57 percent SiO2), and basalts (47-53 percent SiO2).
Where does felsic magma generally form?
subduction zone A. Intermediate and felsic magmas form around convergent margins with a subduction zone. 3. these volcanic mountain chains often form arc shapes, because that is the shape produced when a flat plate (tectonic plate) intersects a sphere (Earth).
Where is felsic found?
Plutonic and hypabyssal felsic rocks may occur as batholiths, plutons, stocks, laccoliths, dikes, sills and plugs. The largest are granitoid batholiths, which are composite intrusions composed of many individual plutons and associated with active continental margins (see Granite and Granitoids).
What is a felsic composition?
Felsic Minerals & Felsic Composition. The term felsic generally refers to rocks or magma that has a silica (SiO2 S i O 2 ) content greater than 63%. Additionally, felsic igneous rocks contain more than 75% felsic minerals which are high in silica content.
How is felsic formed?
Felsic rocks are formed out of the cooling and crystallization of felsic magma or lava. Felsic magma forms out of the melting material beneath Earth's continental crust.
How does magma become felsic?
The processes is called magmatic differentiation by Fractional Crystallization. Because mafic minerals like olivine and pyroxene crystallize first, the process results in removing Mg, Fe, and Ca, and enriching the liquid in silica. Thus crystal fractionation can change a mafic magma into a felsic magma.
Where is felsic magma formed?
subduction zone A. Intermediate and felsic magmas form around convergent margins with a subduction zone. 3. these volcanic mountain chains often form arc shapes, because that is the shape produced when a flat plate (tectonic plate) intersects a sphere (Earth).
How is felsic magma created?
It has been suggested that felsic magmas found at subduction-zone volcanoes are produced by mechanisms including fractional crystallization with or without crustal assimilation8, partial melting of the crust9,10, and partial melting of metasomatised silica-excess pyroxenite mantle11,12.