The BGS Lexicon of Named Rock Units — Result Details
Yarlside Volcanic Formation
| Computer Code: | YRL | Preferred Map Code: | Yrl |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Cautleyan Stage (OU) — Cautleyan Stage (OU) | ||
| Lithological Description: | Pink to pale grey, flow banded rhyolitic vitrophyre (felsite), locally with beds of massive tuff and lapilli-tuff, particularly at the base. | ||
| Definition of Lower Boundary: | Taken at the base of volcanic rocks (generally the felsite, but locally tuff and lapilli-tuff) overlying calcareous siltstone of the Stile End Formation. In part overlies andesite of the Borrowdale Volcanic Group. | ||
| Definition of Upper Boundary: | Defined by the base of the overlying Kirkley Bank Formation. | ||
| Thickness: | Up to 325m | ||
| Geographical Limits: | In the northeastern Lake District, from near Stile End (NY 471 047) to Shap Wells (NY 577 096). | ||
| Parent Unit: | Dent Group (DNT) | ||
| Previous Name(s): | Stockdale Rhyolite
(-542)
Stockdale Rhyolite Formation [Obsolete Name And Code: Replaced By YRL] (SRH) Yarlside Rhyolite [Obsolete Name and Code: Use SRH, YRL] (-3693) Stockdale Rhyolite Member [Obsolete Name and Code: Use YRL] (-3151) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Stockdale Beck, Longsleddale, Cumbria Lawrence et al., 1986 | ||
| Reference(s): | |||
| Kneller, B C, Scott R W, Soper N J, Johnson E W and Allen P M, 1994. Lithostratigraphy of the Windermere Supergroup, Northern England. Geological Journal, Vol. 29, 219-240. | |||
| Lawrence, D J D, Webb, B C, Young, B and White, D E. 1986. The geology of the Late Ordovician and Silurian rocks (Windermere Group) in the area around Kentmere and Crook. Includes map, 1:25,000 series, Parts of Sheets NY40 and SD49 Kentmere and Crook, Solid and Drift Geology. Report of the British Geological Survey, 18/5. | |||
| Millward, D. 2004. A stratigraphical framework for the Upper Ordovician and Lower Devonian volcanic and intrusive rocks in the English Lake District and adjacent areas. British Geological Survey, Research Report: RR/01/007. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E039 E030 | |||