The BGS Lexicon of Named Rock Units — Result Details

Stubble Green Silt Member

Computer Code: SGSI Preferred Map Code: SGS
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Brownish grey (Munsell Soil) sandy silt with shell fragments and diverse assemblages of cold water marine dinoflagellate cysts and foraminifera.
Definition of Lower Boundary: Gradational, conformable contact with dark brown, calcareous, laminated silt and clay of the Carleton Hall Clay Member of the Glannoventia Formation.
Definition of Upper Boundary: Sharp, conformable contact with overlying grey, laminated silty sand of the Kokoarrah Shelly Sand Member of the Glannoventia Formation.
Thickness: To 2.3m
Geographical Limits: West Cumbria, within the Wasdale basin (around Holmrook).
Parent Unit: Glannoventia Formation (GVA)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Nirex Borehole QBH2A (BGS registered borehole SD09NE21), from 49.5 to 51.8m depth. Nirex, 1997. 
Reference(s):
Merritt, J W and Auton, C A. 1997. Quaternary lithostratigraphy of the Sellafield district. Nirex Science Report SA/97/045 (Issue 2.0). [Report prepared for UK Nirex Ltd. 69pp, 5 tables, 20 figures, 14 enclosures and one appendix.] 
Merrit, J W and Auton, C A. 2000. An outline of the lithostratigraphy and depositional history of Quaternary deposits in the Sellafield district, west Cumbria. Proceedings of the Yorkshire Geological Society, Vol.53, 129-154 
Akhurst, M C, Chadwick, R A, Holliday, D W, McCormac, M, McMillan, A A, Millward, D, Young, B, Ambrose, K, Auton, C A, Barclay, W J, Barnes, R P, Beddoe-Stephens, B, James, J C W, Johnson, H, Jones, N S, Glover, B W, Hawkins, M P, Kimbell, G S, MacPherson, K A T, Merritt, J W, Milodowski, A E, Riley, N J, Robins, N S, Stone, P, and Wingfield, R T R. 1997. The geology of the west Cumbria district. Memoir of the British Geological Survey, Sheets 28, 37 and 47 (England and Wales). 138pp. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable