Mafic - Wikipedia
网页A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include basalt, diabase and gabbro. Mafic rocks often also contain calcium-rich varieties of plagioclase ...
Mafic rock | Igneous, Basaltic, Magma | Britannica
网页mafic rock, in geology, igneous rock that is dominated by the silicates pyroxene, amphibole, olivine, and mica. These minerals are high in magnesium and ferric oxides, and their presence gives mafic rock its characteristic dark colour. Mafic rock is commonly contrasted with felsic rock, in which light-coloured minerals predominate.
Felsic and mafic rocks | Igneous, Granitic & Rhyolitic Types
网页Felsic and mafic rocks, division of igneous rocks on the basis of their silica content. Chemical analyses of the most abundant components in rocks usually are presented as oxides of the elements; igneous rocks typically consist of approximately 12 major oxides totaling over 99 percent of the rock.
4.1: Classification of Igneous Rocks - Geosciences LibreTexts
网页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.
What Are Mafic Rocks, their Composition and Examples
网页2023年12月10日 · What are mafic rocks? Mafic rocks are dark-colored igneous rocks rich in magnesium and calcium. These rocks are rich in minerals like pyroxene, olivine, hornblende, and biotite and are associated with calcium-rich plagioclase. Chemically, mafic rocks are relatively low in silica. They usually have 45-52 wt. % silica.
How to Classify Igneous Rocks Into (Ultramafic, Mafic, …
网页Mafic igneous rocks are a group of rocks characterized by their dark color, high magnesium and iron content, and dominance of specific silicate minerals. Mafic igneous Rocks composed mostly of pyroxene, calcium-rich plagioclase, and minor amounts of olivine make up the mafic family of igneous rocks.
Magma | Components, Types, & Facts | Britannica
网页2024年8月27日 · Basaltic (or mafic) magma predominates in nonexplosive volcanic eruptions. It is a high-temperature magma (1,200 °C [about 2,200 °F]) characterized by flowing lava, and it is made up of about 45–55 percent silica (SiO 2) by weight. In contrast, the temperature of rhyolitic (or felsic) magma is much lower (750–850 °C …
Mafic or Basaltic Rock - HyperPhysics
网页The class of rock which crystallizes from silicate minerals at relatively high temperatures is sometimes referred to as "mafic" rock. It is also sometimes called basaltic since the class includes basalt and gabbro. It is in a high temperature range of the Bowen reaction series.
6.7.2: Mafic and Intermediate Igneous Rocks (0% to 20% Quartz)
网页2022年12月16日 · Mafic rocks contain less that 5% quartz, if any. A dark color, due to an abundance of hornblende, clinopyroxene, or olivine, and sometimes Ca-rich plagioclase, characterizes these rocks. They include syenite , monzonite , and gabbro , and their volcanic equivalents trachyte , latite , and basalt .
6.2.1: Mafic and Silicic Magmas - Geosciences LibreTexts
网页2022年12月16日 · Mid-ocean ridge and ocean hot-spot magmas are mostly mafic; subduction zone magmas are generally silicic to intermediate. Continental rifts produce a variety of magma types. Rocks of different compositions have different melting temperatures because some elements combine to promote melting.
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