Jew Limestone Member
Jew Limestone Member (JWL), Carboniferous, Northern England Province
Jew Limestone Member is part of the Alston Formation
Name
No longer bed status, now a member of the Alston Formation. See Johnson and Dunham (1963)[1]; Dunham (1990)[2]; Burgess and Holliday (1979)[3]; Trotter and Hollingworth (1932)[4]; Eastwood et al. (1968)[5]; Johnson and Nudds (1996)[6].
Lithology
Limestone, bioclastic, dark grey, thick wavy beds with fissile mudstone partings, and usually with abundant fossils. At many localities it contains a Saccaminopsis band about two-thirds of the thickness above the base (Burgess and Holliday, 1979[3]). In Cumbria, the member is composed of pale porcellaneous limestone with dark irregular spots (pseudobreccias) at the base, overlain by well-bedded grey and grey-blue limestone crowded with Saccamminopsis fusulinaformis, and in some beds with abundant ‘Lithostrotion’ (Eastwood et al., 1968[5]).
Stratotype
The type section is Force Burn, about 1.2 km upstream from its confluence with the River Tees just above the Cow Green Reservoir, Teesdale, Cumbria (NY 771 306) where the limestone is fossiliferous and contains many colonial corals (Johnson and Dunham, 1963, p. 46[7]). A reference section is a roadside quarry 730 m E25°N of the church in Uldale, Cumbria (NY 2576 3734), with about 6.5 m of dark grey, mostly well-bedded, fossiliferous limestone (including a ‘Lithostrotion band’) beneath about 2 m of grey-white fossiliferous limestone with red spots (see Eastwood et al., 1968, p. 171[5]).
Lower and upper boundaries
The lower boundary is taken at the sharp base of limestone beds overlying a generally conformable ganister sandstone of the Alston Formation (Figure 11, Column 1; Figure 14, Column 3; Figure 15, Column 1), or north of the Lake District resting on a few metres of siltstone, mudstone and sandstone (Figure 14, Column 2).
The upper boundary of the member is overlain, generally conformably, by siltstone and mudstone of the Alston Formation.
Thickness
Between 5 and 9.5 m on the Alston Block and 9.1–12.2 m north of the Lake District massif.
Distribution and regional correlation
A member within the Alston Formation of the Alston and Lake District blocks, and questionably the equivalent of the Oxford Limestone in north Northumberland. It is exposed along the North Pennine escarpment, on the northern flanks of the Lake District massif and in the Vale of Eden, and in Teesdale, Cumbria; also in Weardale, Durham, in the Cowgreen–Maizebeck area and was formerly seen on the site of the Burnhope reservoir in Weardale. Proved at depth in many boreholes and shafts in the northern Pennines of Northumberland and to the east in Durham, including the Rookhope Borehole (BGS Registration Number NY94SW/1) (NY 9375 4278) (Johnson and Nudds, 1996[6]), the Roddymoor and Emma Pit (BGS Registration Number NZ13NE/146) (NZ 1513 3435) (Woolacott 1923[8]) and the Seal Sands Borehole (BGS Registration Number NZ52SW/308) (NZ 538 239). The Jew Limestone is apparently absent in the Allenhead’s No 1 Borehole (BGS Registration Number NY84NE/4) (NY 8604 4539).
Age
Brigantian.
References
- ↑ Johnson, G A L, and Dunham, K C.1963.The geology of Moor House.Monographs of the Nature Conservancy, No 2.
- ↑ Dunham, K C.1990.Geology of The Northern Pennine Orefield: Volume 1, Tyne to Stainmore (2nd edition).Economic Memoir of the British Geological Survey, Sheets 19 and 25, parts 13, 24, 26, 31 and 32 (England and Wales).
- ↑ 3.0 3.1 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)
- ↑ Trotter, F M, and Hollingworth, S E.1932.The geology of the Brampton district.Memoir of the Geological Survey of Great Britain, Sheet 18 (England and Wales).
- ↑ 5.0 5.1 5.2 Eastwood, T, Hollingworth, S E, Rose, W C C, and Trotter, F M.1968.Geology of the country around Cockermouth and Caldbeck.Memoir of the Geological Survey of Great Britain, Sheet 23 (England and Wales).
- ↑ 6.0 6.1 Johnson, G A L, and Nudds, J R. 1996.Carboniferous biostratigraphy of the Rookhope Borehole, County Durham.Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol. 86, 181–226
- ↑ Johnson, G A L, and Dunham, K C.1963.The geology of Moor House.Monographs of the Nature Conservancy, No 2.
- ↑ Woolacot, D.1923.A boring at Roddymoor Colliery, near Crook, Co. Durham.Geological Magazine, Vol. 60, 50–62.