Felsite is a petrologic field term used to refer to very fine-grained or aphanitic, light-colored volcanic rocks which might be later reclassified after a more detailed microscopic or chemical analysis.

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.

2023年12月10日 · 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. These minerals are orthoclase, quartz, and plagioclase. Those with more than 90% are leucocratic. Felsic rocks are usually light-colored.

Felsic and mafic rocks are two main types of igneous rocks, which are rocks that are formed from the cooling and solidification of magma or lava. Felsic rocks are high in silica ( SiO 2 ), while mafic rocks are low in silica.

2023年11月21日 · Felsic rocks are the most common igneous rocks within Earth's continental crust. The most abundant of these rocks are granite and rhyolite. These rocks are composed of varying amounts of quartz,...

2023年12月12日 · 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 …

Felsic and mafic rocks are igneous rocks classified according to their silica content. Chemical analysis of the most abundant components in rocks are commonly presented as oxides of the elements; igneous rocks generally contain about 12 major oxides, which account for over 99 percent of the rock.

Felsic and mafic are two terms used to describe the composition of igneous rocks. These terms refer to the relative proportions of light and dark minerals present in the rocks. Felsic rocks are rich in light-colored minerals, while mafic rocks are dominated by dark-colored minerals.

Felsic refers to a category of igneous rocks and magmas that are rich in silica and light-colored minerals such as quartz and feldspar. This composition significantly influences the characteristics of Earth's crust, the formation of magma, and the classification of igneous rocks based on their mineral content and texture.

Classification of rocks, minerals, and magma based on the silica content present in them defines them as either mafic or felsic. Learn more about the Mafic vs. Felsic geological classification through this ScienceStruck article.