Sep 30, 2020 · All tutors are evaluated by Course Hero as an expert in their subject area. Answer : Mafic minerals are option (b) Pyroxene and option (d) Olivine Step-by-step explanation Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite.
Olivine. In geology, mafic rock is an igneous rock that is ruled by the silicates pyroxene, amphibole, olivine, and mica. These minerals are high in magnesium and ferric oxides, and their presence gives mafic rock its distinctive dark color. Mafic rock is distinguished from felsic rock by the predominance of light-colored minerals.
Which of the following are mafic minerals? (Select all that apply) a. Quartz b. Pyroxene c. Plagioclase d. Olivine 2. Rocks that cool quickly have small crystals. 3. Rocks that cool slowly have large crystals. Igneous Rocks Igneous Rocks Igneous Rocks
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 Minerals and Rocks Remember that igneous rocks are those that are formed from cooled magma. The most common mafic minerals include biotite, hornblende, pyroxene, and olivine. The chemical formulas of these minerals show that they are high in iron and magnesium.
Common examples of mafic rocks are basalt, gabbro, diabase, etc. They are dark in colour ( whereas felsic rocks are light in colour). Chemically, these rocks are consist of magnesium, iron, and calcium.
Igneous Rocks by Composition Igneous rocks are classified according to their mineral content: Ultramafic rocks are dominated by olivine and/or pyroxene. Mafic rocks are dominated by plagioclase and pyroxene (even if you can't see them with the naked eye) and smaller amounts of olivine.
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.
Mafic Igneous Rocks: Examples The most common mafic igneous rocks are the dark-colored gabbro and basalt.Oct 5, 2021
Common rock-forming mafic minerals include olivine, pyroxene, amphibole, biotite mica, and the plagioclase feldspars. Mafic magmas are usually produced at spreading centers, and represent material which is newly differentiated from the upper mantle. Common mafic rocks include basalt and gabbro.
Image DescriptionsIgneous RocksFelsicMaficBiotite and/or Amphibole0 to 20%0 to 30%Pyroxene0%20 to 75%Olivine0%0 to 25 %IntrusiveGraniteGabbro4 more rows
Peridotite is a very dense, coarse-grained, olivine-rich, ultra- mafic intrusive rock. It is noted for its low silica content, and contains very little or no feldspar ( orthoclase, plagioclase).
Mafic minerals are: Olivine, Augite(Pyroxene), Hornblende(amphibole), Biotite mica, Ca-rich plagioclase feldspar. They're rich in magnesium and ferric(iron) and form at a higher temperature. Sialic(Felsic) minerals are: Quartz, Orthoclase feldspar, Muscovite mica, Na-rich plagioclase feldspar.
These elements combine within a melt to form silicate minerals, the most common minerals of igneous rocks. These silicate minerals include feldspars (plagioclase feldspar, potassium feldspar), quartz, micas (muscovite, biotite), pyroxenes (augite), amphiboles (hornblende), and olivine.Oct 2, 2018
Common Minerals in Igneous RocksPotassium feldsparQuartzPlagioclase feldspar (same page as K-feldspar)Hornblende (an amphibole)Muscovite (a mica)Biotite (a mica; same page as muscovite)Augite (a pyroxene)Olivine