How would you describe the texture of an igneous rock that formed extremely slow underground?
Phaneritic (phaner = visible) textures are typical of intrusive igneous rocks, these rocks crystallized slowly below Earth's surface. As magma cools slowly the minerals have time to grow and form large crystals.
What is the texture of an igneous rock formed underground?
PHANERITIC TEXTURE PHANERITIC TEXTURE – Igneous rocks with large, visible crystals because the rock formed slowly in an underground magma chamber.
How are igneous rocks formed underground?
Igneous rocks are formed from lava or magma. Magma is molten rock that is underground and lava is molten rock that erupts out on the surface. The two main types of igneous rocks are plutonic rocks and volcanic rocks. Plutonic rocks are formed when magma cools and solidifies underground.
What kind of texture does a rock have that cools slowly?
Porphorytic: large mineral cyrstals surrounded by a fine grained matrix (background). This texture forms when slow cooling begins to form large mineral crystals. Before the magma is completely cooled the magma (and its large mineral grains) moves closer to the surface and finishes cooling at a more rapid pace.
What is the texture of an igneous rock formed from magma that cooled slowly deep underground?
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.
How is the texture of an igneous rock related to the rate at which it cooled?
There are two fundamental properties of igneous rocks that are used to assign a name. Texture — the size of the crystals can be crudely related to the rate of cooling. The higher the rate of cooling the smaller the size of the crystals.
What type of texture do igneous rocks have?
Igneous textures are used by geologists in determining the mode of origin of igneous rocks and are used in rock classification. The six main types of textures are phaneritic, aphanitic, porphyritic, glassy, pyroclastic, and pegmatitic.
Which types of rocks are formed underground?
Igneous rocks are formed from melted rock deep inside the Earth. Sedimentary rocks are formed from layers of sand, silt, dead plants, and animal skeletons. Metamorphic rocks formed from other rocks that are changed by heat and pressure underground.
When igneous rock is formed from magma cooling slowly inside the earth what type of texture will it have?
porphyritic texture A porphyritic texture is developed when magma that has been slowly cooling and crystallising within the Earth's crust is suddenly erupted at the surface, causing the remaining uncrystallised magma to cool rapidly. This texture is characteristic of most volcanic rocks.
What is the texture of an igneous rock formed from magma that cooled slowly deep underground quizlet?
Igneous rock that formed from magma that hardened beneath Earth's surface. Slowly cooling magma forms coarse-grained rocks, such as granite, with large crystals.
How is the texture of an igneous rock that cools underground intrusive different from an igneous rock that cools above ground extrusive )?
Extrusive igneous rocks cool much more rapidly than intrusive rocks. The rapid cooling time does not allow time for large crystals to form. So igneous extrusive rocks have smaller crystals than igneous intrusive rocks.
How do you describe the texture of an igneous rock?
Igneous textures include the rock textures occurring in igneous rocks. Igneous textures are used by geologists in determining the mode of origin of igneous rocks and are used in rock classification. The six main types of textures are phaneritic, aphanitic, porphyritic, glassy, pyroclastic, and pegmatitic.
How do you describe the texture of a rock?
The texture of a rock is the size, shape, and arrangement of the grains (for sedimentary rocks) or crystals (for igneous and metamorphic rocks). Also of importance are the rock's extent of homogeneity (i.e., uniformity of composition throughout) and the degree of isotropy. The…
How do you describe igneous rocks?
Igneous rocks (from the Latin word for fire) form when hot, molten rock crystallizes and solidifies. The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface.
Why does magma cool slowly underground?
If magma is trapped underground in an igneous intrusion, it cools slowly because it is insulated by the surrounding rock. Crystals have more time to grow to larger size.
Which texture of igneous rocks describes crystals that are greater than 1 cm due to very slow cooling of magma?
If magma cools slowly, deep within the crust, the resulting rock is called intrusive or plutonic. The slow cooling process allows crystals to grow large, giving the intrusive igneous rock a coarse-grained or phaneritic texture.
When magma solidifies below the surface of the Earth what possible igneous rocks may form?
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 is the texture of an igneous rock formed from magma that cools slowly deep underground Regents?
Igneous rock that formed from magma that hardened beneath Earth's surface. Slowly cooling magma forms coarse-grained rocks, such as granite, with large crystals. Intrusive Rocks have larger grains than extrusive rocks. Rapidly cooling lava forms fine-grained rocks with small crystals or no crystals at all.
Which igneous texture would most likely communicate that the magma cooled slowly underground in a magma chamber?
4.1. If magma cools slowly, deep within the crust, the resulting rock is called intrusive or plutonic. The slow cooling process allows crystals to grow large, giving intrusive igneous rock a coarse-grained or phaneritic texture. The individual crystals in phaneritic texture are readily visible to the unaided eye.
Why do igneous rocks that solidify underground cool so slowly?
Answer and Explanation: Igneous rocks that solidify underground cool so slowly because they are insulated. There are layers of rock and soil above them that trap the heat…
What is the texture of igneous rocks with crystals smaller than 1mm?
Thus few crystals will form and they will not grow to any large size. The resulting texture will be glassy, with a few tiny crystals called microlites. A completely glassy texture is called holohyaline texture….
| <1 mm | fine grained |
|---|---|
| 1 – 5 mm | medium grained |
| 5 – 3 cm | coarse grained |
| > 3 cm | very coarse grained |
Feb 12, 2004
Which of the following is the texture that could describe the texture of extrusive igneous rock?
aphanitic texture Extrusive igneous rocks have a fine-grained or aphanitic texture, in which the grains are too small to see with the unaided eye.
When magma solidifies below the surface of the Earth what possible igneous rock may form a andesite B basalt C granite D scoria?
Examples include basalt, rhyolite, andesite, and obsidian. Intrusive, or plutonic, igneous rocks form when magma cools slowly below the Earth's surface.
What is the size of the crystals if the rock cools slowly and forms below the Earth’s surface?
If the magma cools slowly, then the crystals have enough time to grow and become large. Some granites contain minerals which are up to one meter (3 ft) across! The size of crystals in an igneous rock is an important indicator of the conditions where the rock formed.
What igneous rock cools slowly underground and contains mostly quartz and potassium?
These rocks are both classified as granitic, because they both are rich in quartz. Granite contains mostly potassium feldspars and has a low percentage of dark iron and magnesium minerals.
What is coarse grained texture?
(a) Said of a crystalline rock, and of its texture, in which the individual minerals are relatively large; specif. said of an igneous rock whose particles have an average diameter greater than 5 mm (0.2 in.).
How is the texture describe if an igneous rock?
The texture of an igneous rock (fine-grained vs coarse-grained) is dependent on the rate of cooling of the melt: slow cooling allows large crystals to form, fast cooling yields small crystals.
When magma solidifies below the surface of the Earth what possible igneous rock may formed?
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.
When magma solidifies below the surface of the Earth what possible igneous rock may from?
Intrusive Intrusive, or plutonic, igneous rocks form when magma cools slowly below the Earth's surface. Most intrusive rocks have large, well-formed crystals. Examples include granite, gabbro, and diorite.
What is an igneous rock describe the method of formation and characteristics of igneous rock?
Igneous rocks form when magma (molten rock) cools and crystallizes, either at volcanoes on the surface of the Earth or while the melted rock is still inside the crust. All magma develops underground, in the lower crust or upper mantle, because of the intense heat there.