Oxford Limestone Member
Contents
Oxford Limestone Member (OXL), Carboniferous, Northern England Province[edit]
Oxford Limestone Member is part of the Alston Formation
Name[edit]
Known alternatively as the Greenses Limestone. See Frost and Holliday (1980[1]); Burgess and Holliday (1979[2]); Day (1970[3]); Fowler (1926[4]); George and Black (1971[5]); Gunn (1900[6]); Gunn and Clough (1895[7]).
Lithology[edit]
Limestone, thick bedded at base, becoming thin bedded at top; grey to dark grey with numerous red-weathered Osagia (an alga) haloes; particularly rich in corals and brachiopods.
Stratotype[edit]
The type section is near Broomlee Lough, Northumberland (NY 7903 6990 and 7960 7041). Frost and Holliday (1980, p. 32[1]) noted this locality in the grey to dark grey fossiliferous limestone with Osagia (‘Girvanella’) haloes, which is 5–6 m thick in the Bellingham district (Figure 11, Column 3).
Lower and upper boundaries[edit]
The lower boundary is taken at the generally conformable, sharp base of the first bed of limestone that overlies measures of the Alston Formation. This typically displays a coal or seatearth immediately below the limestone.
The upper boundary of the member is taken at the top of the uppermost limestone bed that is overlain by a coarsening upwards sequence of dark grey mudstones, siltstone and sandstone, the first containing ironstone nodules.
Thickness[edit]
Between 5 and 6 m.
Distribution and regional correlation[edit]
Widespread limestone member occurring throughout the Northumberland Trough in northern England and the Scottish Borders within the Alston Formation, stratigraphically lying below the Eelwell Limestone (Figure.12, Column 1–4; Figure 13, Column 3). Some authors correlate the Oxford Limestone with the Jew Limestone of the Alston Block and north of the Lake District (George and Black, 1971[5]) and with the Bridge Limestone in the Bewcastle and Langholm area (Day, 1970[3]) (Figure 10, Column 3; Figure.11, Column.2).
Age[edit]
Brigantian.
References[edit]
- ↑ 1.0 1.1 Frost, D V, and Holliday, D W.1980.Geology of the country around Bellingham.Memoir of the Geological Survey of Great Britain, Sheet 13 (England and Wales).
- ↑ Burgess, I C, and Holliday, D W.1979.Geology of the country around Brough-under-Stainmore.Memoir of the Geological Survey of Great Britain, Sheet 31, parts 25 and 30 (England and Wales).
- ↑ 3.0 3.1 Day, J B W.1970.Geology of the country around Bewcastle.Memoir of the Geological Survey of Great Britain, Sheet 12 (England and Wales).
- ↑ Fowler, A.1926.The geology of Berwick on Tweed, Norham and Scremerston.Memoir of the Geological Survey of Great Britain, Sheets 1 and 2 (England and Wales).
- ↑ 5.0 5.1 George, T N, and Black, W W.1971.The Lower Carboniferous(Dinantian) of England, Wales and Scotland. International Strati-graphical Lexicon, Part 3a Vii. International Union of Geological Sciences.
- ↑ Gunn, W.1900.The geology of Belford, Holy Island, and the Farne Islands, Northumberland.Memoir of the Geological Survey of Great Britain, Sheet 4 (England and Wales).
- ↑ Gunn, W, and Clough, C T.1895.The geology of part of Northumberland, including the country between Wooler and Coldstream.Memoir of the Geological Survey of Great Britain, Sheet 3 (England and Wales).
