Also called hardpan, this is a hardened layer of soil formed by calcium deposits. Caliche develops over thousands of years in arid and semi-arid regions when calcium from groundwater collects as the water evaporates.
"Typic Petrocalcid (loamy-skeletal, mixed, thermic)" by Soil Science is licensed under CC BY.
A01 The Blessing Way (01-07) p. 199
A07 The Dark Wind (04-06), p. 121
Encyclopædia Britannica Online N.d. Calcrete. http://www.britannica.com/EBchecked/topic/89145/calcrete, accessed November 17, 2014.
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