Is Granite Extrusive Or Intrusive Igneous Rock

They are formed by the cooling of molten magma on the earth s surface.

Is granite extrusive or intrusive igneous rock.

Some cool so. Intrusive igneous rocks crystallize below earth s surface and the slow cooling that occurs there allows large crystals to form. Derived from the words feldspar and silica to describe an igneous rock having abundant light colored minerals such as quartz feldspars or muscovite. The two main categories of igneous rocks are extrusive and intrusive.

Extrusive igneous rocks are formed when molten magma spill over to the surface as a result of a volcanic eruption. Igneous rocks form from magma that erupted onto the surface as lava where it cooled quickly. Intrusions are one of the two ways igneous rock can form. Gabbro and granite are examples of intrusive igneous rocks.

Intrusive or plutonic igneous rocks form when magma cools slowly below the earth s surface most intrusive rocks have large well formed crystals. Intrusive rocks are formed. Key terms felsic. Intrusive rocks are very hard in nature and are often coarse grained.

Examples of intrusive igneous rocks are diabase diorite gabbro granite pegmatite and peridotite. Extrusive igneous rocks cool and solidify more quickly than intrusive igneous rocks. The magma on the surface lava cools faster on the surface to form. Extrusive igneous rocks erupt onto the surface where they cool quickly to form small crystals.

Many mountain ranges such as the sierra nevada in california are formed mostly from large granite or related rock intrusions. See sierra nevada batholith. The other is extrusive rock that is a volcanic eruption or similar event. For example two rocks from identical magma can become either rhyolite or granite depending on whether they cool quickly or slowly.

Extrusive igneous rocks also known as volcanic rocks are formed at the crust s surface as a result of the partial melting of rocks within the mantle and crust. Igneous rocks are classified into two groups depending upon where the molten rock solidifies. On the other hand intrusive igneous rocks form from magma that cooled slowly deep.