Felsic - Wikipedia
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, and have low temperatures to keep the felsic minerals molten.
霏细结构_百度百科
这种微晶结构称为霏细结构（felsic texture），是 隐晶质结构 的一个变种。 常见于浅色火山岩或 浅成岩 ，岩石由极细小的他形粒状石英和长石的隐晶物质集合体所组成，不具 斑晶 或具少量斑晶。
Felsic and mafic rocks | Igneous, Granitic & Rhyolitic Types
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.
4.1: Classification of Igneous Rocks - Geosciences LibreTexts
Igneous rocks are classified based on texture and composition. Texture describes the physical characteristics of the minerals, such as grain size. This relates to the cooling history of the molten magma from which it came. Composition refers to the …
Felsic Rock Composition and Examples | Geology Base
Dec 10, 2023 · 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.
6.3: Classification of Igneous Rocks - Geosciences LibreTexts
May 16, 2024 · Igneous rocks can be divided into four categories based on their chemical composition: felsic, intermediate, mafic, and ultramafic. The diagram of Bowen’s reaction series (Figure 7.7) shows that differences in chemical composition correspond to differences in the types of minerals within an igneous rock.
[科普中国]-霏细结构- · 科普中国网
Dec 31, 2021 · 霏细结构（felsic texture），又称长英质结构，是指仅有石英和长石组成的微晶结构。 常见于酸性岩中。 简介脱玻化达到一定程度时，可形成极细的、它形的长英质矿物颗粒的隐晶质集合体，颗粒间界线模糊，形状不规则。
Igneous Rocks – Types, Properties, and Examples - Science Notes …
Jan 31, 2024 · Igneous rocks are classified based on their texture, mineral composition, and the environment of formation. The key factors include: Texture: Grain size, shape, and arrangement of crystals. Composition: Based on the silica content, they are categorized as felsic, intermediate, mafic, or ultramafic.
5.3: Igneous Rock Classification - Geosciences LibreTexts
Apr 11, 2024 · Extrusive igneous rocks have a fine-grained or aphanitic texture, in which the grains are too small to see with the unaided eye. The fine-grained texture indicates the quickly cooling lava did not have time to grow large crystals.
4.3 Classification of Igneous Rocks – Principles of Earth Science
Igneous rocks can be divided into four categories based on their chemical composition: felsic, intermediate, mafic, and ultramafic. The diagram of Bowen’s reaction series (Figure 4.6) shows that differences in chemical composition correspond to differences in the types of minerals within an igneous rock.