Describe the texture and composition of this common igneous rock granite. See the igneous rock classification diagram below the sample. Granite is an intrusive igneous rock and coarse grained. It has a felsic composition. Granite is an extrusive igneous rock and is fine grained. il . ias a felsic composition. Granite is an intrusive igneous rock and coarse grained. It has a mafic composition. Granite is an extrusive igneous rock and fine grained. It has a mafic composition.
The Correct Answer and Explanation is:
The correct answer is:
Granite is an intrusive igneous rock and coarse-grained. It has a felsic composition.
Explanation:
Granite is classified as an intrusive igneous rock, meaning it forms beneath the Earth’s surface from the cooling and solidification of magma. As magma cools slowly at depth, it allows crystals to grow large, giving granite its coarse-grained texture. This means that the individual mineral crystals in granite, such as feldspar, quartz, mica, and sometimes amphibole, are large enough to be seen with the naked eye.
In terms of composition, granite is felsic, meaning it is rich in light-colored minerals such as quartz and feldspar. Felsic rocks have a high silica content (about 70% or more), which makes them less dense compared to mafic rocks. The light color and higher concentration of quartz and feldspar distinguish granite from mafic rocks, which contain darker minerals like olivine and pyroxene.
Granite typically has a high silica content which is characteristic of felsic rocks. The high silica concentration results in the rock having a relatively low melting point and being more viscous than mafic rocks. This can lead to a slower cooling process, which allows the formation of large crystals. Granite is often used in construction and countertops because of its durability, attractive appearance, and resistance to weathering.
On the other hand, if granite were an extrusive igneous rock, it would be formed from lava that cools quickly on the Earth’s surface, resulting in a fine-grained texture. Extrusive igneous rocks, such as basalt, have a different mineral composition, typically being mafic in nature, rich in iron and magnesium.
Therefore, the key characteristics of granite are that it is an intrusive rock with a coarse-grained texture and a felsic composition.