Editing Vertisol (section)

==Composition==
Vertisols have a high content of [[expansive clay]] minerals (many of them belonging to the [[montmorillonite]]s) that form deep cracks in drier seasons or years. In a phenomenon known as [[argillipedoturbation]], alternate shrinking and swelling causes ''self-ploughing'', where the soil material consistently mixes itself, causing some vertisols to have an extremely deep [[A horizon]] and no [[B horizon]]. (A soil with no B horizon is called an ''A/C soil''). This heaving of the underlying material to the surface often creates a microrelief known as ''[[gilgai]]''.

Vertisols typically form from highly [[base (chemistry)|basic]] rocks, such as [[basalt]], in climates that are seasonally humid or subject to erratic [[droughts]] and [[floods]], or that impeded drainage. Depending on the parent material and the climate, they can range from grey or red to the more familiar deep black (known as "black earths" in Australia, "black gumbo" in East Texas, "black cotton" soils in East Africa, and "turf soil" or "vlei soils" in South Africa).