felsyczne

Felsic is a term used in geology to describe igneous rocks that are rich in lighter-colored minerals such as quartz, feldspar, and muscovite. These minerals are typically silicate minerals containing aluminum and alkali metals like sodium and potassium. The word "felsic" itself is a portmanteau derived from the terms "feldspar" and "silica."

Felsic rocks are generally less dense and have lower melting points compared to mafic rocks, which are rich in darker minerals like pyroxene and olivine. Due to their higher silica content, felsic rocks tend to be lighter in color, often appearing white, pink, or light gray. Examples of common felsic igneous rocks include granite, rhyolite, and syenite. Granite is a coarse-grained intrusive rock, while rhyolite is its fine-grained extrusive equivalent. Syenite is similar to granite but contains less or no quartz.

These rocks are commonly found in the Earth's continental crust. Their formation is often associated with processes involving partial melting of the crust and fractional crystallization, where certain minerals crystallize out of a melt before others, leading to a concentration of felsic minerals. Felsic magma is more viscous than mafic magma, which can lead to more explosive volcanic eruptions.