Computer Code: |
SNS |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Marsdenian Substage (CZ)
— Marsdenian Substage (CZ) |
Lithological Description: |
A grey and pale brown, fine-grained, feldspathic, sandstone, thinly-to thickly-bedded with subordinate beds of mudstone with sideritic ironstone; ripple-laminated in upper part. |
Definition of Lower Boundary: |
The lower boundary is taken at the base of the first sandstone-dominated unit above fissile black mudstone that includes a Bilinguites bilinguis (R2b1) Marine Band. |
Definition of Upper Boundary: |
The upper boundary is taken at the base of a mudstone-dominated succession (Millstone Grit Group, undivided) overlying the uppermost leaf of the Sheen Sandstones. |
Thickness: |
25 m thick. |
Geographical Limits: |
Restricted to the area around Sheen, Staffordshire, SK 11 62. |
Parent Unit: |
Millstone Grit Group [See Also MIGR] (MG)
|
Previous Name(s): |
Lower Sheen Grit; Upper Sheen Grit [Obsolete Name and Code: Use SNS]
(-1835)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
Sheen, Staffordshire, displaying numerous exposures in streams and on Sheen Hill. Aitkenhead et al. 1985. |
Reference Section |
Sheen Sandstones (Lower Leaf), section in stream gully east of Ridge End, Staffordshire exposes 16.46 m of thin and thickly-bedded grey and pale brown fine-grained sandstone and interbedded silty mudstone with sideritic ironstone. Aitkenhead et al. 1985. |
Reference Section |
Sheen Sandstones (Middle Leaf), stream section south of Moorhouse (Staffs) exposes thinly-bedded ripple-laminated grey-brown fine grained micaceous sandstone. Aitkenhead et al., 1985. |
Reference(s): |
Aitkenhead, N, Chisholm, J I, and Stevenson, I P. 1985. Geology of the country around Buxton, Leek and Bakewell. Memoir of the British Geological Survey, England and Wales Sheet 111. |
Bisat, W S and Hudson, R G S. 1943. The Lower Reticuloceras (R1) goniatite succession in the Namurian of the North of England. Proceedings of the Yorkshire Geological Society, Vol. 24 Pt. 6, 383-438. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E111
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