Igneous Textures (original) (raw)

Geologists like igneous textures because they reveal so much about how a rock formed. The first set of textures focuses on the size of mineral crystals. Crystal size primarily reflects the rate of cooling, but is also often strongly affected by rock composition (especially water or gas content). Both intrusive and extrusive rock textures are represented.

The second set of textures is associated with volcanic rocks. Explosive volcanism creates highly distinctive features in igneous rocks.