The BGS Lexicon of Named Rock Units — Result Details

Harlock Formation [Obsolete: use BKR]

Computer Code: HRG Preferred Map Code: HRG
Status Code: Full
Age range: Wenlock Epoch (SW) — Wenlock Epoch (SW)
Lithological Description: [Obsolete: use BKR] Interbedded greywacke, sandstones and siltstones. Underlying and overlying laminated silty mudstone.
Definition of Lower Boundary: Incoming of greywacke, sandstones and siltstones above silty mudstones of Brathay Formation.
Definition of Upper Boundary: By base of overlying Horrace Formation - laminated silty mudstone.
Thickness: c.250 metres. (Lateral variations ~200 = ~300 metres).
Geographical Limits: Not defined.
Parent Unit: none recorded or not applicable
Previous Name(s): Harlock Grits [Obsolete Name and Code: Use HRG] (-4713)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Ulverston, Sheet 48. 
Reference(s):
Rose, W C C. 1977. Geology and Hematite deposits of South Cumbria. Economic Memoir for 1:50,000 Sheet 58 and southern part of Sheet 48. Memoir of the geological Survey of Great Britain. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E048