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The BGS Lexicon of Named Rock Units — Result Details

Tufa

Computer Code: TUFA Preferred Map Code: notEntered
Status Code: Index Level
Age range: Quaternary Period (Q) — Quaternary Period (Q)
Lithological Description: Tufa is a sedimentary rock composed of calcium carbonate or silica, formed by evaporation as a thin, surficial, soft, spongy, semifriable encrustation around the mouth of springs, seeps or along streams carrying calcium carbonate in solution, and exceptionally as a thick deposit along lake shores. Travertine is a hard, dense variety of tufa; it also occurs in caves as stalactites and stalagmites. Synonyms: sinter, travertine.
Definition of Lower Boundary: none recorded or not applicable
Definition of Upper Boundary: none recorded or not applicable
Thickness: none recorded or not applicable
Geographical Limits: none recorded or not applicable
Parent Unit: Chemical deposits (CHEMD)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
none recorded or not applicable
Reference(s):
McMillan, A A and Powell, J H. 1999. The classification of artificial (man made) ground and natural superficial deposits. British Geological Survey Research Report, RR/99/04. 
Hallsworth, C R, and Knox, R W O'B. 1999. BGS Rock Classification Scheme Volume 3. Classification of sediments and sedimentary rocks. British Geological Survey Research Report, RR 99-03. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E237 E014 E203 E219 E217