The rock formed from slow cooling magma below the surface has large crystals because the crystals have had a large amount of time, because of the insulating effects of the surrounding material, to gather elements necessary for crystal production as they move around in the liquid material. Once solidified, crystal growth stops.
When magma cools slowly below Earth's surface, it forms rocks with large crystals. This slow cooling allows more time for crystals to grow to a larger size compared to rocks that cool quickly at the surface. Examples of these rocks include granite and diorite.
Magma beneath the Earth's surface cools and solidifies to form mineral crystals. This process takes place over long periods of time, allowing different types of crystals to form depending on the minerals present in the magma.
Intrusive igneous rocks.
Crystals are generally formed when magma or molten rock cools and solidifies. Rapid cooling of the molten rock generally results in the formation of small crystals, like when magma reaches the surface. However, if they cool down slowly, then large crystals are formed. Keeping heat applied allows more growth on the crystal over time. In that logic, larger crystals grow underground.
Magma.
Magma that cools below Earth's surface forms igneous rocks, specifically intrusive or plutonic rocks. As the magma cools slowly, it allows large crystals to develop, resulting in rocks like granite or diorite. These rocks are typically coarse-grained due to the extended cooling period, which allows minerals to crystallize fully.
When tiny crystals form in magma, they create an igneous rock known as "intrusive" or "plutonic" rock. This occurs when magma cools slowly beneath the Earth's surface, allowing the crystals to grow larger, such as in granite. If the magma cools quickly on the surface, it forms "extrusive" or "volcanic" rock, like basalt, where the crystals are much smaller.
Gabbro forms from a magma that is rich in iron and magnesium, and poor in silica (quartz). The magma cools and crystallizes deep below the earth's surface. Gabbro is from the same kind of magma as basalt and diabase, but because it cools more slowly, it develops larger crystals.
When magma cools and crystallizes below Earth's surface, the igneous rocks formed are called intrusive or plutonic igneous rocks. These rocks, such as granite and diorite, typically have large mineral crystals due to the slow cooling process that occurs underground. This slow cooling allows for the growth of visible crystals, distinguishing them from extrusive igneous rocks, which form from lava that cools quickly at the surface.
Igneous rock, such as granite or diorite, is formed from magma that cools below the Earth's surface. It has a coarse-grained texture due to the slow cooling process, allowing large mineral crystals to form.
The rock formed from slow cooling magma below the surface has large crystals because the crystals have had a large amount of time, because of the insulating effects of the surrounding material, to gather elements necessary for crystal production as they move around in the liquid material. Once solidified, crystal growth stops.
No, they do not form on the surface of the Earth. They are formed by the crystallization of magma within the Earth. All you have to remember is an intrusive rock forms within the Earth.