Brownber Formation
Brownber Formation (BNBF), Carboniferous, Northern England Province
Brownber Formation is part of the Great Scar Limestone Group
Name
The name is derived from Brownber, near Newbiggin-on-Lune, Westmorland; see Tiddeman (in Aveline and Hughes, 1888[1]); Mitchell (1978)[2]; Pattison (1990)[3]; Millward et al. (2003)[4].
Lithology
The sedimentary rocks of the Brownber Formation comprise interbedded sandstone (fine-grained, pale brown, laminated in part), limestone (calcarenites, grainstones, oolitic in part) and dolostone (yellow and flaggy) containing abundant quartz pebbles in distinctive and laterally discontinuous beds near the top.
Genetic interpretation
Interpretations include a shoreline (beach) deposit (Barraclough, 1983[5]; Leeder, 1988[6]) and deposition in a tidal, high and low energy environment (Millward et al., 2003[4]).
Stratotype
Reference sections occur in old quarries north of Bousfield, Park and Dawns (NY 6102 0922 to 6107 0924) including beds of limestone and sandstone (with gaps), at or near the top of the formation, 4.8 m thick; and in a stream section north of Orton Village Green from (NY 6241 0844 to 6243 0851) which includes sandstone and limestone (with gaps) 6.7 m thick (see Pattison, 1990[3]).
Lower and upper boundaries
The sandstones of the Brownber Formation overlie limestones of the Coupland Sike Limestone Member (Scandal Beck Limestone Formation) (Figure.9, Column.16), but the boundary is poorly known in the Ravenstonedale area (see Pattison, 1990[3]; McCormac, 2001[7]).
Within the Stainmore Trough, an unconformity is present at the base of the overlying dark grey limestone of the Breakyneck Scar Limestone Formation which comprises packstone or grainstone with mudstone/siltstone interbeds.
Thickness
About 15–80 m thickness is recorded in the Orton area with 10–40 m in the Appleby district.
Distribution and regional correlation
The Ravenstonedale, Shap and Appleby area.
Age
Chadian (Millward et al., 2003[4]) or Arundian (George et al., 1976, pp. 38–39, fig. 11, col. D[8]; Mitchell, 1978, pp..172–173, fig. 60, col. D[9] after Taylor et al., 1971[10]).
References
- ↑ Aveline, W T, and Hughes, T McK.1888.The geology of the country around Kendal, Sedbergh, Bowness and Tebay.Memoir of the Geological Survey of Great Britain, Sheet 98NE (England and Wales)
- ↑ Mitchell, M.1978.Dinantian.168–177 in The geology of the Lake District. Moseley, F (editor).Occasional Publication of the Yorkshire Geological Society, No. 3
- ↑ 3.0 3.1 3.2 Pattison, J.1990.Geology of the Orton and Sunbiggin Tarn districts: 1:10 000 sheets NY60NW and NE.British Geological Survey Technical Report, WA/90/12
- ↑ 4.0 4.1 4.2 Millward, D, McCormac, M, Hughes, R A, Entwistle, D C, Butcher, A, and Raines, M G.2003.Geology of the Appleby district.Sheet explantion of the British Geological Survey,Sheet 30 (England and Wales)
- ↑ Barraclough, R.1983.Tectonic versus eustatic sea-level changes in the Lower Carboniferous of northern England: a sedimentary study. Unpublished PhD thesis, University of Leeds
- ↑ Leeder, M R.1988.Recent developments in Carboniferous geology: a critical review with implications for the British Isles and NW Europe.Proceedings of the Geologists Association, Vol. 99, 73–100
- ↑ McCormac, M.2001.The Upper Palaeozoic rocks of the Shap and Penrith district, Edenside, Cumbria.British Geological Survey Research Report, RR/01/10
- ↑ George, T N, Johnson, G A L, Mitchell, M, Prentice, J E, Ramsbottom, W H C, Sevastopulo, G D, and Wilson, R B.1976.A correlation of Dinantian rocks in the British Isles.Geological Society of London Special Report, No.7
- ↑ Mitchell, M.1978.Dinantian.168–177 in The geology of the Lake District. Moseley, F (editor).Occasional Publication of the Yorkshire Geological Society, No. 3.
- ↑ Taylor, B J, Burgess, I C, Land, D H, Mills, D A C, Smith, D B, and Warren, P T.1971.British regional geology: northern England (4th edition). (London: HMSO for Institute of Geological Sciences.)