The BGS Lexicon of Named Rock Units — Result Details
Carham Limestone Bed
| Computer Code: | CHML | Preferred Map Code: | notEntered |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Courceyan Substage (CF) — Chadian Substage (CI) | ||
| Lithological Description: | White, nodular dolomitic limestone with MgCO3 content of 38.95% (Robertson et al., 1949), interbedded with chert. | ||
| Definition of Lower Boundary: | Conformable boundary on sedimentary rocks, mainly mudstone and siltstone, of the Ballagan Formation. | ||
| Definition of Upper Boundary: | Conformable boundary with overlying interbedded mudstone, siltstone and sandstone of the Ballagan Formation. | ||
| Thickness: | To 7.5 m. | ||
| Geographical Limits: | Local development in the Ballagan Formation on the north and south banks of the River Tweed; best development around Carham, Northumberland. | ||
| Parent Unit: | Ballagan Formation (BGN) | ||
| Previous Name(s): | Carham Stone [Obsolete Name and Code: Use CHML]
(-4538)
Carham Limestone [Obsolete Name and Code: Use CHML] (-2084) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Section in Nottylees Quarry (disused), 550 m southeast of former Carham Station, Northumberland, 4 m of interbedded dolomite and chert overlain by sandstone, dip to east at low angle. Robertson et al., 1949. | ||
| Partial Type Section | North bank of the River Tweed, 1.25 km eastnortheast of Birgham, natural section in up to 2 m of cherty, dolomitic white limestone interbedded with mudstone and siltstone. BGS Duns Survey, NT83NE (McMillan, 2006). | ||
| Reference(s): | |||
| Robertson, T, Simpson J B and Anderson J G C. 1949. The Limestones of Scotland. Special reports on the mineral resources of Great Britain. Vol.35. Memoir of the Geological Survey. | |||
| Greig, D C. 1971. British Regional Geology: the South of Scotland (3rd Edition). (Edinburgh: HMSO for the Institute of Geological Sciences.) | |||
| Dean, M T, Browne, M A E, Waters, C N, and Powell, J H. 2011. A lithostratigraphical framework for the Carboniferous successions of northern Great Britain (onshore). British Geological Survey Research Report RR/10/007. 165 pp. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E003 S026 | |||