The BGS Lexicon of Named Rock Units — Result Details

Rosedale Ironstone Member

Computer Code: RDLI Preferred Map Code: RI
Status Code: Full
Age range: Toarcian Age (JT) — Toarcian Age (JT)
Lithological Description: Ooid-ironstone in grainstone texture, greenish-brown, brown and purplish, cross-bedded, with bioclastic lenses and laminae and subordinate sideritic mudstone beds; ooids are of berthierine (chamosite) with pores filled with siderite and calcite cement; basal phosphatised pebble bed.
Definition of Lower Boundary: Non-sequence/disconformity: ooid-ironstone with basal pebble bed sharply overlying yellow-weathering fine-grained sandstone and siltstone of the Low Baring Member (Young, 1994) of the Blea Wyke Sandstone Formation.
Definition of Upper Boundary: Unconformity: ferruginous coarse-grained sandstone with lignite fragments and calcareous bioclasts and a basal ooidal ironstone bed with phosphatised gravel-grade clasts (Low House Sandstone Member of Dogger Formation) overlying ooid-ironstone beds of Rosedale Ironstone Member.
Thickness: Generally up to 4m, very locally (Hollins Mines: Kitching's and Garbutt's deposits) possibly up to 25m.
Geographical Limits: Restricted to four areas in Rosedale and Fryup Dale (Rosedale East Mines, Sheriff's Pit, Hollins Mines (Kitching's and Garbutt's deposits) and Stanch Bullen) in the North York Moors, where the member lies within the cores of shallow, possibly part fault-bounded, synclinal structures, inferred to be closed, and unconformably overlain by the Dogger Formation (Middle Jurassic).
Parent Unit: Blea Wyke Sandstone Formation (BW)
Previous Name(s): Stanch Bullen Ironstone (-2996)
Rosedale East Ironstone (-4291)
Sheriff Pit Oolite (-3635)
Alternative Name(s): none recorded or not applicable
Partial Type Section  Bank sections below upper tramway at Rosedale East Mines, Rosedale; exposing up to 0.65m of the base of the member overlying the Low Baring Member. Young, 1994, p.135, fig. 3. 
Reference Section  Adit into Sheriff's Pit mine, Rosedale; exposes about 2m of member including top, beneath Dogger Formation. Young, 1994, p.135, fig. 3. 
Whitehead, T H, Anderson, W, Wilson, V, and Wray, D A. 1952. The Liassic Ironstones. Memoir of the British Geological Survey, The Mesozoic Ironstones of England. 
Rastall, R H and Hemingway, J E. 1943. The Yorkshire Dogger III. Upper Eskdale. Geological Magazine, Vol.80, 209-230. 
Young, T P. 1994. The Blea Wyke Sandstone Formation (Jurassic, Toarcian) of Rosedale, North Yorkshire, UK. Proceedings of the Yorkshire Geological Society, Vol. 50, 129-142. 
Rayner, D H, and Hemingway, J E (editors). 1974. The geology and mineral resources of Yorkshire. (Leeds: Yorkshire Geological Society.) 
Rastall, R H and Hemingway, J E. 1949. The Yorkshire Dogger IV. Rosedale and Farndale. Geological Magazine, Vol.86, 201-225, 265-278. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable