The BGS Lexicon of Named Rock Units — Result Details
Grain Heads Siltstone Member
Computer Code: | GHD | Preferred Map Code: | GHD |
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Status Code: | Full | ||
Age range: | Telychian Age (ST) — Telychian Age (ST) | ||
Lithological Description: | Highly fossiliferous silty mudstones, siltstones and fine-grained sandstones. | ||
Definition of Lower Boundary: | Conformable: green-grey bioturbated mudstones immediately overlying medium- to coarse-grained sandstones of the Cock Rig Formation. | ||
Definition of Upper Boundary: | Conformable: highest laminated sandy siltstones and fine-grained sandstones with abundant bioclasts on bedding planes, below Lamb Rig Siltstone Member. | ||
Thickness: | 30-55m | ||
Geographical Limits: | Pentland Hills, Midland Valley. | ||
Parent Unit: | Wether Law Linn Formation (WLN) | ||
Previous Name(s): | Lower Member, Wether Law Linn Formation [Obsolete Name and Code: Use GHD]
(-2203)
Beds D to E [Obsolete Name and Code: Use GHD] (-1559) Beds At D To E (-929) Lower part of Bed C [Obsolete Name and Code: Use GHD] (-281) Lower part of fossiliferous mudstones and siltstones [Obsolete Name and Code: Use GHD] (-3432) Units A to C, Wether Law Linn Formation [Obsolete Name and Code: Use GHD] (-3433) |
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Alternative Name(s): | none recorded or not applicable | ||
Stratotypes: | |||
Reference Section | Deerhope Burn, North Bank, 600m ESE from Wether Law Summit | ||
Partial Type Section | Top of Grain Heads Siltstone Member and base of Lambrig Siltstone Member, North Esk river. | ||
Type Section | Wether Law Linn, 140m to 290m upstream from confluence with North Esk river. | ||
Reference(s): | |||
Peach, B N and Horne, J. 1899. The Silurian Rocks of Britain, Volume 1. Scotland. Memoir of the Geological Survey of the United Kingdom. | |||
Howell, H H and Geikie, A, 1861. The Geology of the neighbourhood of Edinburgh (1st edition). Memoir of the Geological Survey, Scotland. | |||
Robertson, G, 1989. A palaeoenvironmental interpretation of the Silurian rocks in the Pentland Hills, near Edinburgh, Scotland. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol.80, 127-141. | |||
Lamont, A, 1952. Ecology and correlation of the Pentlandian - a new division of the Silurian System in Scotland. 27-32 in Faunal and floral facies and zonal correlation. Dighton-Thomas, H (editor). Report of the 18th Session of the International Geological Congress, Great Britain, 1948, Pt.10. | |||
Tipper, J C, 1976. The stratigraphy of the North Esk Inlier. Scottish Journal of Geology, Vol.12, Pt, 15-22. | |||
Mitchell, G H. 1962. The geology of the neighbourhood of Edinburgh. (Explanation of Sheet 32) Third Edition. (Reprinted 1980). Memoir of the Geological Survey of Great Britain (Scotland). | |||
Robertson, G, 1986. North Esk Inlier. 174-185 in Lothian Geology. An Excursion Guide. McAdam, A D and Clarkson, E N K (editors). [Edinburgh: Scottish Academic Press.] | |||
Henderson, J and Brown, D J, 1870. On the Silurian rocks of the Pentland Hills. Transactions of the Edinburgh Geological Society, Vol.1, 266-272. | |||
1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
S032 |