1. Extrusive Igneous Rocks: These are rocks formed when magma cools and solidifies on the Earth's surface. They have a fine-grained texture because the magma cools quickly.
* Basalt: This dark-colored, fine-grained rock is formed from mafic (magnesium and iron rich) magma. It's common in shield volcanoes and oceanic eruptions.
* Andesite: This intermediate-colored rock is formed from intermediate magma, containing both mafic and felsic (silica-rich) minerals. It's typical of stratovolcanoes.
* Rhyolite: This light-colored, fine-grained rock is formed from felsic magma. It's often associated with explosive eruptions.
2. Intrusive Igneous Rocks: These are rocks formed when magma cools and solidifies underground. They have a coarse-grained texture because the magma cools slowly.
* Gabbro: This dark-colored, coarse-grained rock is the intrusive equivalent of basalt.
* Diorite: This intermediate-colored, coarse-grained rock is the intrusive equivalent of andesite.
* Granite: This light-colored, coarse-grained rock is the intrusive equivalent of rhyolite.
Other Volcanic Rocks:
* Pyroclastic Rocks: These are fragments of volcanic material (ash, cinders, bombs) that solidify after being ejected from a volcano. They can be classified based on their size and composition.
* Scoria: This vesicular (containing holes) rock is formed from basaltic lava.
* Pumice: This light-colored, very porous rock is formed from felsic lava.
Remember: A single eruption can produce a variety of rock types, depending on the different phases and intensity of the event.
