How Are Igneous Rocks Formed?
If need the answer to the question of "how are igneous rocks formed?," you can find out here. Another name for igneous rocks is fire rocks. They can be formed both underground and above the ground. There are three different kinds of igneous rocks: intrusive, extrusive and hypabyssal.
Intrusuve igneous rocks. Igneous rocks form underground from magma. Magma is extremely hot melted rock that comess from the center of the earth. The magma sometimes become trapped in pockets underground. These pockets allow the magma to slowly cool and harden. Because the cooling process is very slow, intrusive igneous rocks tend to be very coarse allowing the minerals to be seen easily with the naked eye.
Extrusive igneous rocks. These igneous rocks are formed above the ground when volcanoes erupt. The magma rises and flows out of the volcano and becomes lava. When the lava hardens it forms igneous rocks. Since the cooling process is much faster above the earth, extrusive igneous rocks have a much finer grain. It is also possible for extrusive igneous rocks to form under the ocean. These are called submarine igneous rocks.
Hypabyssal igneous rocks. These type of igneous rocks are very rare and are associated with the formation of dykes and sills. They are formed at a depth that is in between the intrusive and extrusive rocks. They are formed when a huge rock mass splits and the lava forces its way through. The lava does not do anything to change the split, but hardens along the sides and within cracks and other places it can get to. This causes dykes and sills to form.