The BGS Lexicon of Named Rock Units — Result Details
Nodular Limestone Member
| Computer Code: | NOL | Preferred Map Code: | NL |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Homerian Age (SH) — Homerian Age (SH) | ||
| Lithological Description: | Limestone, grey, buff, nodular, interbedded with green-grey, calcareous mudstone; sporadic beds of bioclastic limestone and sparse bentonitic tuffs; sparse limestone bioherms (reefs). | ||
| Definition of Lower Boundary: | Gradational passage taken at the base of the first predominantly calcareous mudstone and nodular limestone overlying the bedded, limestone-dominated Lower Quarried Limestone Member. | ||
| Definition of Upper Boundary: | Base of the limestone-dominated Upper Quarried Limestone Member, overlying limestone with grey calcareous mudstone partings. | ||
| Thickness: | 31.1 - 37.8m at Wren's Nest, Dudley. | ||
| Geographical Limits: | West Midlands. | ||
| Parent Unit: | Much Wenlock Limestone Formation (WEL) | ||
| Previous Name(s): | Nodular Beds [Obsolete Name And Code: Use NOL]
(NOB)
Nodular Member [Obsolete Name and Code: Use NOL] (-4222) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Reference Section | Wren's Nest Geological Trail, Dudley; The Quarry, locality 4 of Cutler and others, 1990. | ||
| Reference Section | Wren's Nest Geological Trail, Dudley; locality 3 of Cutler and others, 1990. | ||
| Type Section | Wren's Nest Geological Trail, Dudley; NCC cutting to south side of Wren's Hill Road and in associated quarry workings; locality 2 of Cutler and others, 1990. | ||
| Reference Section | Castle Hill, Dudley; canal basin, locality CH 12 of Butler, 1939. | ||
| Reference(s): | |||
| Bassett, M G. 1974. Review of the stratigraphy of the Wenlock Series of the Welsh Borderlands and South Wales. Palaeontology, 17, 745-777. | |||
| Butler, A J. 1939. The stratigraphy of the Wenlock Limestone of Dudley. Quarterly Journal of the Geological Society of London, 95, 37-74. | |||
| Cutler, A, Oliver, P G and Reid, C G R, 1990. Wren's Nest National Nature Reserve. Geological Handbook and Field Guide. Nature Conservancy Council/Dudley MBC. | |||
| Butler, A J. 1937. On Silurian and Cambrian rocks encountered in a deep boring at Walsall, South Staffordshire. Geological Magazine, Vol. 74, 241-257. | |||
| Powell, J H, Glover, B W and Waters, C N, 1992. A Geological background for planning and development in the `Black Country'. British Geological Survey Technical Report WA/92/33. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E168 E154 E167 | |||