The BGS Lexicon of Named Rock Units — Result Details
Calmy Limestone
| Computer Code: | CAL | Preferred Map Code: | CAL |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Arnsbergian Substage (CG) — Arnsbergian Substage (CG) | ||
| Lithological Description: | A pale to dark grey, fine-grained, crinoidal, bioclastic, limestone, interpreted to be of marine origin, generally with two or more leaves separated by about 30cm partitions of mudstone, one leaf of "calmy" type being off-white, fine-grained and massive with a conchoidal fracture. The name is not geographical in origin, but instead indicates a "hard, pale grey or fawn, fine-grained, muddy limestone with a conchoidal fracture". | ||
| Definition of Lower Boundary: | Generally seen as a change from a marine mudstone which has the Edmondia punctatella Band at its base with the Upper Hirst Coal beneath in the Clackmannan basin within the Upper Limestone Formation. | ||
| Definition of Upper Boundary: | Commonly seen as a change to a thick marine mudstone, that passes up into deltaic arenaceous deposits within the Upper Limestone Formation. | ||
| Thickness: | From 0.5m to 4.5m in the Airdrie, Falkirk and Glasgow districts, and 15m in shelf settings in Ayrshire. | ||
| Geographical Limits: | Throughout the outcrop and subcrop of the Upper Limestone Formation in the Midland Valley of Scotland. | ||
| Parent Unit: | Upper Limestone Formation (ULGS) | ||
| Previous Name(s): | Janet Peat Limestone [Obsolete Name and Code: Use CAL]
(-2045)
Arden Limestone [Obsolete Name and Code: Use CAL] (-3267) Robroyston Limestone [Obsolete Name and Code: Use CAL] (-3268) Dykeneuk Limestone [Obsolete Name and Code: Use CAL] (-105) Garnkirk Limestone [Obsolete Name and Code: Use CAL] (-106) Gair Limestone (-746) Hirst Limestone (-747) |
||
| Alternative Name(s): | Blue Tour Limestone |
||
| Stratotypes: | |||
| Type Area | Arden 'basin', southwest of Glasgow. Hinxman et al., 1920. | ||
| Reference Section | Seen in two leaves 1.98m thick, with the base at a depth of 510.24m in the Mossneuk Borehole, BGS No. NS88NE/204, south of Alloa. | ||
| Reference(s): | |||
| Hinxman, L W, Anderson, E M and Carruthers, R G. 1920. The economic geology of the Central Coalfield of Scotland, Area IV; Paisley, Barrhead, Renfrew. Memoir of the Geological Survey, Scotland. | |||
| Francis, E H, Forsyth, I H, Read, W A and Armstrong, M. 1970. The geology of the Stirling district. Memoir of the Geological Survey of Great Britain, Sheet 39 (Scotland). | |||
| Hall, I H S, Browne, M A E and Forsyth, I H. 1998. Geology of the Glasgow district. Memoir of the British Geological Survey, Sheet 30E (Scotland). | |||
| Monro, S K. 1999. Geology of the Irvine District. Memoir of the British Geological Survey, Sheet 22W and part of 21E (Scotland). | |||
| Forsyth, I H, Hall, I H S and McMillan, A A. 1996. Geology of the Airdrie district. Memoir of the British Geological Survey, Sheet 31W (Scotland). | |||
| Cameron, I B, Aitken, A M, Browne, M A E and Stephenson, D. 1998. Geology of Falkirk District. Memoir of the British Geological Survey Sheet 31E (Scotland). | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| S015 S023 S031 S031 S023 S033 S032 S040 S030 S039 S039 S040 S041 | |||