The BGS Lexicon of Named Rock Units — Result Details

Tuttle Hill Member

Computer Code: THQ Preferred Map Code: THQ
Status Code: Full
Age range: Comley Series (EC) — Comley Series (EC)
Lithological Description: Pink to maroon, medium- to fine-grained glauconitic sandstone. Subordinate mudstone beds and near-ubiquitous mudstone drapes. Tabular-planar and compound cross-bedding common. Summary of typical lithologies in Type Section:(i) Sandstone, maroon, fine, glauconitic and micaceous. Smooth, flat-topped beds, parallel-sided with horizontal lamination. Many bed tops bioturbated (56m). (ii) Sandstone, pink to maroon, glauconitic. Undulatory, smooth-topped beds with mudstone drapes. Compound cross-bedding with highly lenticular bed forms (39m). (iii) Sandstone, maroon to pinkish grey, glauconitic. Parallel-sided, smooth-topped beds with horizontal or gently dipping lamination; mudstone beds locally constitute 50% of succession (10.5m). (iv) Sandstone, maroon to pale pink, glauconitic. In thick tabular-planar cross-bedded sets, showing unimodal current directions, or in lenticular compound cross-bedded sets. Ubiquitous mudstone drapes (39m). (v) Sandstone, grey, coarse to pebbly. In lenticular, thick beds with tabular-planar cross-bedding showing bimodal current directions. Mudstone interbeds are lenticular, locally to 0.7m thick (7.5m). (vi) Horizontally laminated sandstone, mudstone dominant at base (5.3m).
Definition of Lower Boundary: Base of beds with abundant mudstone-draped top surfaces. Sandstones beneath (of Park Hill Member) predominantly grey, with herringbone cross-bedding in main part.
Definition of Upper Boundary: Incoming of variegated fine-grained sandstone and siltstone beds of Jees Member. Bimodal cross-bedding and trough cross-bedding becomes well-developed.
Thickness: 157m in type section.
Geographical Limits: From Nuneaton town centre, extending north-west for 5.2km to Worthington Farm, Mancetter.(SP 3541 9205-3192 9572).
Parent Unit: Hartshill Sandstone Formation (CQ)
Previous Name(s): Tuttle Hill Quartzite (-3725)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Southeast face of Hartshill Quarry, 600m west-north-west of Hill Farm. (SP 3425 9360). 
Reference(s):
Brasier, M D, Hewitt, R A and Brasier, C J, 1978. On the late Precambrian - Early Cambrian Hartshill Formation of Warwickshire. Geological Magazine, Vol.115/1, p.21-36. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E169