Plutonic Rocks (Deep Intrusions)
* Granite: A very common, coarse-grained rock with a light color. It's typically composed of quartz, feldspar, and mica. Found in mountain ranges and used for building materials.
* Diorite: A medium-grained, typically gray rock. It has less quartz than granite and more plagioclase feldspar. It's often found in association with granite.
* Gabbro: A dark-colored, coarse-grained rock composed mainly of plagioclase feldspar and pyroxene. It's found in oceanic crust and some mountain ranges.
* Peridotite: A very dense, dark-colored rock that is the main component of the Earth's upper mantle. It is rich in olivine and pyroxene.
Hypabyssal Rocks (Shallow Intrusions)
* Dolerite (Diabase): A dark-colored, fine-grained rock with a distinctive, often columnar, texture. It's commonly found as dikes and sills.
* Quartz Porphyry: A rock with large, distinct quartz crystals embedded in a finer-grained matrix. It's often associated with gold and silver deposits.
* Pegmatite: A very coarse-grained, often exceptionally large-crystallized rock, often containing rare minerals. It's often found in association with granite.
Key Characteristics of Intrusive Igneous Rocks:
* Crystals: Intrusive rocks typically have larger crystals than extrusive rocks because they cool slowly beneath the Earth's surface.
* Texture: Intrusive rocks often have a more uniform and less porous texture.
* Location: They are found within the Earth's crust, often exposed after erosion.
Let me know if you'd like more details on any of these rock types!
