What are the characteristics of mafic magma?
Mafic magmas are low in silica and contain more dark, magnesium and iron rich mafic minerals, such as olivine and pyroxene. Felsic magmas are higher in silica and contain lighter colored minerals such as quartz and orthoclase feldspar. The higher the amount of silica in the magma, the higher is its viscosity.
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).
How does magma differentiate?
Magmatic differentiation can occur by the chemical reaction between the magma and the first crystals to solidify out of it, or by the physical separation of the first crystals that form from the remaining magma, either through settling to the bottom of a magma chamber or through crustal deformations that cause the …
What are the three major types of magma and how are they distinguished from one another in terms of their physical properties?
There are three basic types of magma: basaltic, andesitic, and rhyolitic, each of which has a different mineral composition. All types of magma have a significant percentage of silicon dioxide. Basaltic magma is high in iron, magnesium, and calcium but low in potassium and sodium.
How is mafic magma formed?
Primary mafic magmas are thought to be generated by melting of the mantle wedge with an influx of slab-derived water-rich materials3,4. Intermediate to felsic magmas (andesite to rhyolite) are also commonly produced in many subduction zones.
What does mafic mean?
Definition of mafic : of, relating to, or being a group of usually dark-colored minerals rich in magnesium and iron.
What are two processes that cause magma differentiation?
Among the processes are:
- Distinct melting events from distinct sources.
- Various degrees of partial melting from the same source.
- Crystal fractionation.
- Mixing of 2 or more magmas.
- Assimilation/contamination of magmas by crustal rocks.
- Liquid Immiscibility.
What is magmatic differentiation quizlet?
Magmatic differentiation is the formation of one or more secondary magmas from a single parent magma. At any stage in the evolution of a magma, the solid and liquid components can separate into two chemically distinct units.
What is the difference between basaltic magma and rhyolitic magma list at least three characteristics for each type of magma?
List at least three characteristics for each type of magma. Basaltic Magma has a low silica content, causing it to have a low viscosity. Contrary, Rhyolitic Magma has a high silica content, causing it to have a high viscosity. Basaltic Magma is very mild and quiet, while Rhyolitic Magma is catastrophic.
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 the difference between mafic and felsic?
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. Mafic rocks are darker in color than felsic rocks.
Where does mafic magma come from?
In general, melting of a mantle source (garnet peridotite) results in mafic/basaltic magmas. Melting of crustal sources yields more siliceous magmas. In general more siliceous magmas form by low degrees of partial melting.