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What can you tell about an igneous rock that is coarse texture?
Igneous rocks may be divided into two categories. Intrusive or plutonic rocks crystallize from magma beneath the earth’s surface. Magmas and their resultant plutonic rock bodies cool and crystallize slowly and are characterized by coarse-grained texture, in which the mineral crystals are visible to the unaided eye.
What can you tell about an igneous rock that is coarse-grained apex?
Answer: Coarse-grained igneous rocks occur when large crystals grow while the magma cools, usually this type of purple is called intrusive igneous rock. Explanation: The intrusive igneous rocks can be recognized by their large intercrossed crystals, which develop slowly while the magma is gradually cooled.
What is a coarse-grained igneous rock?
Coarse grain varieties (with mineral grains large enough to see without a magnifying glass) are called phaneritic. Granite and gabbro are examples of phaneritic igneous rocks. Fine grained rocks, where the individual grains are too small to see, are called aphanitic. The most common glassy rock is obsidian.
What are coarse-grained igneous rocks and how do they form?
Coarse-grained igneous rocks form when magma cools slowly within Earth. How are igneous rocks classified according to composition? Igneous rocks can be classified by composition based on the major minerals in the rocks. Light-colored rocks have granitic compositions.
How many different kinds of igneous rocks are there?
two
The two main categories of igneous rocks are extrusive and intrusive. Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet.
What crystal sizes are found in igneous rocks?
Crystals have more time to grow to larger size. In smaller intrusions, such as sills and dykes, medium-grained rocks are formed (crystals 2mm to 5 mm). In large igneous intrusions, such as batholiths, coarse-grained rocks are formed, with crystals over 5mm in size.
What are the two types of igneous rocks?
The two main categories of igneous rocks are extrusive and intrusive. Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet.