BGS Rock Classification Scheme
Duricrust - A type of residual deposit. It is a general term for a hard crust on the surface of, or layer in, the upper horizons of a soil in a semiarid climate. It is an indurated product of surface and near-surface processes formed by cementation or replacement of bedrock, weathering deposits, unconsolidated sediments, soil or other materials produced by low-temperature physiochemical processes. British Geological Survey Research Report RR/99/03, section 13.6; RR/99/04, appendix 2.
| Code | DURI |
|---|---|
| Description | Duricrust - A type of residual deposit. It is a general term for a hard crust on the surface of, or layer in, the upper horizons of a soil in a semiarid climate. It is an indurated product of surface and near-surface processes formed by cementation or replacement of bedrock, weathering deposits, unconsolidated sediments, soil or other materials produced by low-temperature physiochemical processes. British Geological Survey Research Report RR/99/03, section 13.6; RR/99/04, appendix 2. |
| Qualifiers | No qualifiers currently exist. |
| Definition | Rudaceous pedogenic sedimentary rock. Clasts >50% from pre-existing siliceous rocks, cemented by calcium carbonate & >50% or predominantly gravel-grade, >2mm. Formed on/in upper soil layers in semi-arid areas. See calcrete/caliche/ferricrete/silcrete. |
| Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/DURI |
CAVEAT
"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.