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.

Which of the following describes the way how basaltic magma can generate felsic magma quizlet?

Which of the following describes the way how basaltic magma can generate felsic magma? In continental settings, rising basaltic magma can melt low-density silica-rich rocks generating a secondary melt of felsic magma.

How are 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.

What happens when basaltic magma hardens?

What about when basaltic magma hardens? Basalt forms when basaltic lava hardens; obsidian and pumice form when basaltic magma hardens, with this rapid cooling they are very light because of the gas. When basaltic magma hardens, gabbro might also form. A rock has a porphyritic texture.

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).

What makes a rock felsic?

In order for a rock to be classified as felsic, it generally needs to contain more than 75% felsic minerals (namely quartz, orthoclase and plagioclase). Rocks with greater than 90% felsic minerals can also be called leucocratic, from the Greek words for white and dominance.

How are basaltic magmas thought to be formed?

How are basaltic magmas thought to be formed? A basaltic pond of magma becomes trapped below continental crust and partially melts this silica-rich crust into a granitic magma.

How can a magma body change its composition?

If the magma absorbs part of the rock through which it passes we say that the magma has become contaminated by the crust. Either of these process would produce a change in the chemical composition of the magma unless the material being added has the same chemical composition as the magma.

Is basalt felsic?

Granite and rhyolite are considered felsic, while basalt and gabbro are mafic (click here for more information on mafic and felsic).

How can the generation of basaltic magma in a subduction zone lead to more felsic rocks?

A large heat source is required for forming large volumes of felsic crustal melts and is usually supplied by the mantle via basalt. Hydrous arc basalt formed by cold slab subduction is voluminous and its heat transfer with high water content may have melted crustal rocks leading to effective felsic magma production.

What happens once basaltic magma is formed?

Basaltic magma is usually very dense and gets stopped in the continental crust rather than reaching the surface, causing it to crystallize. This crystallization releases the basaltic magma's heat, causing the temperature of the continental crust to rise and melt.

Why will magma become more felsic as it ages?

2) If as a magma is cooling, the crystallizing minerals are removed (by settling out of the liquid, or by pressure squeezing the liquid away), then these minerals will deplete the system in those elements that are concentrated in mafic minerals. Thus the magma becomes more felsic in composition.

What is the meaning of felsic?

Definition of felsic : consisting of or chiefly consisting of feldspar or feldspathoid quartz.

What does basalt change into?

Intense heat or great pressure transforms basalt into its metamorphic rock equivalents. Depending on the temperature and pressure of metamorphism, these may include greenschist, amphibolite, or eclogite.

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.

What is basaltic magma?

Basaltic (or mafic) magma predominates in nonexplosive volcanic eruptions. It is a high-temperature magma (1,200 °C (about 2,200 °F)) characterized by flowing lava, and it is made up of about 45–55 percent silica (SiO2) by weight.

Is basalt felsic or mafic?

mafic Granite and rhyolite are considered felsic, while basalt and gabbro are mafic (click here for more information on mafic and felsic). Felsic rocks, in general, form the bulk of the continental plates, while mafic basalt forms the seafloor.

Is basalt mafic or felsic?

Can basalt be metamorphosed?

Chemical reactions between the heated seawater and basalt result in metamorphism of the basalt. Hydrothermal metamorphism can also occur on continents where crustal rocks are metamorphosed by invading, hot fluids associated with igneous intrusions.

Is basalt mafic felsic or intermediate?

Igneous Rocks by Composition

Coarse-Grained Textures	Fine-Grained Textures
Peridotite = Ultramafic	Komatiite (Ultramafic, but too rare to worry about at this point in your life)
Gabbro = Mafic	Basalt = Mafic
Diorite = Intermediate	Andesite = Intermediate
Granite = Felsic	Rhyolite = Felsic

Is basaltic magma mafic?

There are three major types of magma. Basaltic (or mafic) magma predominates in nonexplosive volcanic eruptions. It is a high-temperature magma (1,200 °C (about 2,200 °F)) characterized by flowing lava, and it is made up of about 45–55 percent silica (SiO2) by weight.

What does basalt turn into metamorphic rock?

schist

Summary Chart of Common Metamorphic Rocks
Original Rocks	Metamorphic Equivalent	Metamorphism
clay-rich rock	hornfels	contact
granite	gneiss	regional
basalt	schist	regional

What does basalt turn into?

What type of metamorphism is basalt?

Hydrothermal Metamorphism Hydrothermal Metamorphism (Fig. 8.3): typically occurs along mid-ocean ridge spreading centers where heated seawater percolates through hot, fractured basalt. Chemical reactions between the heated seawater and basalt result in metamorphism of the basalt.