Bransty Cliff Sandstone Member

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Bransty Cliff Sandstone Member (BYCS), Carboniferous, Northern England Province[edit]

Bransty Cliff Sandstone Member is a member of the Whitehaven Sandstone Formation and is part of the Warwickshire Group

Name[edit]

Previously named the Whitehaven Sandstone by Eastwood et al. (1931[1]; see also Akhurst et al., 1997[2]; Brockbank, 1891[3]; Jones, 1993[4]).

Lithology[edit]

Red, to deep purple or purplish brown, cross-bedded, micaceous, medium- to coarse-grained sandstone, with subsidiary mudstone and siltstone interbeds, and thin palaeosols.

Genetic interpretation[edit]

The unit was deposited from a major braided river system that flowed from the north-east. The reddening was either primary or early diagenetic.

Stratotype[edit]

The type section is the Whitehaven harbour cliffs (NX 9735 1950 to 9750 1895) where the mainly sandstone and subsidiary mudstone and siltstone interbeds of the member are well exposed.

Lower and upper boundaries[edit]

The lower boundary, at the base of the lowest major reddened channel sandstone unit, is unconformable cutting down to the interbedded mudstones, siltstones, and sandstones, with coal seams, of the Pennine Middle Coal Measures Formation (Figure 14, Column 1).

The upper boundary with the mudstone dominated Millyeat Member, is at the top of the highest major channel sandstone unit in the Bransty Cliff Sandstone Member.

Thickness[edit]

Greater than 100 m

Distribution and regional correlation[edit]

The West Cumbria Coalfield.

Age[edit]

Bolsovian (Westphalian C) to Asturian (Westphalian D).

References[edit]

  1. Eastwood, T, Dixon, E E L, Hollingsworth, S, and Smith, B.1931.The geology of the Whitehaven and Workington District.Memoir of the Geological Survey, Sheet 28 (England and Wales).
  2. Akhurst, M C, Chadwick, R A, Holliday, D W, McCormac, M, McMillan, A A, Millward, D, and Young, B.1997.Geology of the west Cumbria district.Memoir of the British Geological Survey, Sheets 28, 37 and 47 (England and Wales).
  3. Brockbank, W.1891.On the occurrence of the Permian, Spirorbis limestones, and Upper Coal Measures at Frizington Hall in the Whitehaven district.Memoir of the Proceedings of the Manchester Literary and Philosophical Society, Vol. 4, 418–426.
  4. Jones, N S.1993.Stratigraphical and sedimentological characteristics of the ‘Whitehaven Sandstone Series’, Westphalian C, West Cumbria coalfield.British Geological Survey Technical Report, WH/93/102R.