The BGS Lexicon of Named Rock Units — Result Details
Hollowbrook Member
| Computer Code: | HOB | Preferred Map Code: | notEntered |
|---|---|---|---|
| Status Code: | Pending Upgrade | ||
| Age range: | Emsian Age (DE) — Eifelian Age (DI) | ||
| Lithological Description: | Mainly sandstone, grey, quartzitic, clean, parallel-laminated, with inter-bedded cross-laminated units and some mudstone interbeds. Ladder ripples and reactivation surfaces are present. Local channels filled with flaser and lenticular beds. Trace fossil Arenicolites and Tentaculitids. | ||
| Definition of Lower Boundary: | Conformable on rocks of the Lynton Formation (q.v.). | ||
| Definition of Upper Boundary: | Overlain ?conformably by rocks of the Trentishoe Member (q.v.). | ||
| Thickness: | 70m (Tunbridge, 1978) | ||
| Geographical Limits: | North Devon - west Somerset | ||
| Parent Unit: | Hangman Sandstone Formation (HASA) | ||
| Previous Name(s): | Trentishoe Grits
(-960)
Hollowbrook Formation [Obsolete Name and Code: Use HOB] (-4097) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Cliff top exposures at Hollowbrook, about 1.5km west of Woody Bay, near Lynton, North Devon. | ||
| Reference(s): | |||
| Tunbridge, I P. 1978. North Devon - Lower and Middle Devonian: Hangman Sandstone Group. 9-13 in Scrutton, C T (Editor), A field guide to selected areas of the Devonian of south-west England. International Symposium on the Devonian System. (PADS 78). (Palaeontological Association). | |||
| Lane, R. 1965. The Hangman Grits - an introduction and stratigraphy. Proceedings of the Ussher Society, Vol.1, 166-167. | |||
| Evans, J W. 1922. The geological structure of the country round Combe Martin. Proceedings of the Geologists' Association, Vol.33, 201-228. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| none recorded or not applicable | |||