The BGS Lexicon of Named Rock Units — Result Details

Freshney Sandstone Member

Computer Code: FESA Preferred Map Code: notEntered
Status Code: Full, pending ratification
Age range: Oxfordian Age (JO) — Oxfordian Age (JO)
Lithological Description: Moderately thick beds of fine- to medium-grained, poorly to moderately cemented sandstone separated by dark grey-brown, carbonaceous mudstones.
Definition of Lower Boundary: The base is defined by a down-section change from sandstones to mudstones (Heather Formation); a down-section increase in gamma-ray values and a slight decrease in velocity.
Definition of Upper Boundary: The top is defined by a sharp down-section change from mudstones (Heather Formation) to sandstones; a sharp decrease in gamma-ray values; and a slight increase in velocity.
Thickness: Up to 60.5 m.
Geographical Limits: Confined to North Sea Block 30/6. Although thin un-named sandstones of the same age have been recorded in several wells in adacent areas of the Central Graben, the Freshney Sandstone Member is only known from its type section (Richards et al., 1993).
Parent Unit: Heather Formation (HTHE)
Previous Name(s): Jacqui Sandstones (-5142)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  North Sea well 30/6-3 between depths 4773 and 4833.5 m below KB (Richards et al., 1993). 
Reference(s):
Richards, P C, Lott, G K, Johnson, H, Knox, R W O'B. and Riding, J B. 1993. 3. Jurassic of the Central and Northern North Sea. In: Knox, R W O'B and Cordey, W G. Lithostratigraphic nomenclature of the UK North Sea. [British Geological Survey, Nottingham] 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable