The BGS Lexicon of Named Rock Units — Result Details
Kentmere Pike Tuff Formation
| Computer Code: | KMR | Preferred Map Code: | Kmr |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Caradoc Series (O4) — Caradoc Series (O4) | ||
| Lithological Description: | A dacitic lapilli-tuff, with flow joints, localised breccia and some interbeds of tuff, lapilli-tuff and volcaniclastic sandstone. It is laterally impersistent, possibly filling hollows in an erosion surface, interpreted as a densely welded, rheomorphic high-grade ignimbrite. | ||
| Definition of Lower Boundary: | Taken at the abupt change from volcaniclastic sedimentary rocks of the Seathwaite Fell Sandstone Formation to dacitic lapilli-tuff indicating an erosion surface, which is usually obscured by later, syn-BVG andesite intrusions. | ||
| Definition of Upper Boundary: | Overlain by eutaxitic lapilli-tuff of the Lincomb Tarns Tuff Fomration, but the relationships are obscured by later syn-BVG andesite intrusions. | ||
| Thickness: | To 350m | ||
| Geographical Limits: | The east side of Kentmere Valley [NY 468 081], via Hallow Bank Quarter and Kentmere Pike [NY 465 078] to the west side of Longsleddale [NY 471 079]. | ||
| Parent Unit: | Borrowdale Volcanic Group (BVG) | ||
| Previous Name(s): | Kentmere Pike Formation [Obsolete Name and Code: Use KMR]
(-2270)
Kentmere Formation [Obsolete Name and Code: Use KMR, GSD] (-2218) Kentmere Pike Rhyolites (-943) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Area | Kentmere Pike and Hallow Bank Quarter, Kentmere, Cumbria. Johnson, E W (In prep.) | ||
| Reference(s): | |||
| Mitchell, G H, 1929. The succession and structure of the Borrowdale Volcanic Series in Troutbeck, Kentmere and the western part of Long Sleddale (Westmorland). Quarterly Journal of the Geological Society of London, Vol. 85, 9-44. | |||
| Soper, N J and Numan, N M S, 1974. Structure and stratigraphy of the Borrowdale Volcanic Rocks of the Kentmere area, English Lake District. Geological Journal, Vol. 9, 147-166. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E030 E039 | |||