How is andesite different from rhyolite and basalt?

Answer 1

There are rocks that are extrusive (formed quickly on the surface of the earth) or intrusive (formed within the earth under slow cooling). Both types of extrusive or intrusive rocks can vary in composition from mafic (high iron and magnesium content) to silicic (less heavy ions like Fe and Mg, but with more of the lighter elements like Ca, Na, K, etc.). Extrusive rocks range from most mafic to less mafic as such: Basalt, Andesite, Rhyolite (and are all fine-grained b/c they cooled quickly). Intrusive rocks that cool more slowly and have larger crystals range from most mafic to less mafic as such: Gabbro, Diorite, Granite. Basalt and gabbro have a similar composition, just the crystal size differs from different cooling rates (same for rhyolite and granite).

Answer 2

In terms of most of its properties, andesite is in between rhyolite and basalt. Rhyolite is rich in silica, light in color, and has a low melting point and density compared with other igneous rocks. Basalt is poor in silica, dark in color, dense, and has a high melting point. Andesite has a moderate amount of silica, a moderate melting point, a moderate density, and can rgane from light to dark.

Answer 3

Andesite is an intermediate volcanic rock with a mineral composition between basalt and rhyolite. Basalt is a dark-colored volcanic rock low in silica and high in iron and magnesium, while rhyolite is a light-colored volcanic rock high in silica and lower in iron and magnesium. Andesite has a medium silica content falling between basalt and rhyolite.

Answer 4

They are all extrusive igneous rocks. i.e. they erupt from volcanoes.