The BGS Lexicon of Named Rock Units — Result Details

Malham Formation

Computer Code: MALM Preferred Map Code: notEntered
Status Code: Full
Age range: Holkerian Substage (CQ) — Asbian Substage (CR)
Lithological Description: Massive to weakly bedded, pale grey to very pale grey, medium- to coarse-grained calcarenite packstones and grainstones, and well bedded, thick to very thick-bedded, mid-pale to very pale calcarenite packstones, wackestones and subordinate grainstones.
Definition of Lower Boundary: Drawn at the base of pale grey limestone of the Cove Limestone Member (of the Malham Formation) where is rests conformably (but gradationally and slightly diachronously) on the mid dark-grey limestone of the Scaleber Quarry Member (of the Kilnsey Formation) or, locally, unconformably on Lower Palaeozoic strata.
Definition of Upper Boundary: Drawn at the conformable upward passage from pale grey limestone of the Gordale Limestone Member (of the Malham Formation) to darker grey limestone of the Lower Hawes Limestone at the base of the Alston Formation, Yoredale Group. However, in the Cominco S11 Borehole (SD 8590 6340) (SD86SE/5) the upper boundary of what is probably the Malham Formation is unconformable beneath rocks of the Bowland Shale Formation, Craven Group.
Thickness: 220m south of the Middle Craven Fault to about 140m north of the North Craven Fault.
Geographical Limits: Southern part of the Askrigg Block, North Yorkshire, north of Settle [SD 77 to SD 97].
Parent Unit: Great Scar Limestone Group (GSCL)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Gordale Scar, where the complete thickness (94m) of the Gordale Limestone Member, including top and base, is seen. Arthurton et al. 1988. 
Partial Type Section  Malham Cove, North Yorkshire, where 72m of upper part of Cove Limestone Member, including its top, is present. Arthurton et al. 1988. 
Reference Section  Giggleswick Scar, near Settle, Yorkshire. 
Reference(s):
Arthurton, R S, Johnson, E W, and Mundy, D J C. 1988. Geology of the country around Settle. Memoir of the British Geological Survey, Sheet 60 (England and Wales). 
Mundy, D J C and Arthurton, R S, 1980. Field Meetings: Settle and Flasby. Proceedings of the Yorkshire Geological Society, Vol.43, 32-36. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E060