Search results
Results from the WOW.Com Content Network
Felsic refers to silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. Molten felsic magma and lava is more viscous than molten mafic magma and lava.
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.
Felsic rocks are silica-rich rocks high in minerals like quartz, feldspars, or muscovite and relatively low iron and magnesium minerals. Usually, rocks classified as felsic have at least 75% felsic minerals.
The major mineralogical components of igneous rocks can be divided into two groups: felsic (from feldspar and silica) and mafic (from magnesium and ferrous iron). The felsic minerals include quartz, tridymite, cristobalite, feldspars (plagioclase and alkali feldspar), feldspathoids (nepheline and leucite), muscovite, and corundum.
Identify key minerals: quartz, feldspar, olivine, pyroxene, amphibole. Rocks with quartz and potassium feldspar are typically felsic. Rocks with olivine and pyroxene are typically mafic or ultramafic.
For igneous rock, the composition is divided into four groups: felsic, intermediate, mafic, and ultramafic. These groups refer to differing amounts of silica, iron, and magnesium found in the minerals that make up the rocks.
Felsic rocks are light-colored rocks high in silica and felsic minerals and low in mafic minerals. Due to their high silica content, which is > 63 wt. %, these rocks are sometimes known as silicic or acidic. Examples of felsic rocks are granite, obsidian, rhyolite, dacite, and rhyodacite.
Learn about felsic rocks, including the felsic definition. Discover felsic minerals, felsic rock composition, how felsic magmas form, and if granite is felsic. Updated: 11/21/2023.
Igneous rock composition is divided into four categories: ultramafic, mafic, intermediate and felsic. These categories refer to differing amounts of silica, potassium, sodium, calcium, iron, and magnesium found in the minerals that make up the rocks.