The BGS Lexicon of Named Rock Units — Result Details

East Grange Till Member

Computer Code: EGTI Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Red-brown sandy, silty, matrix-supported diamicton with isolated dropstone cobbles of Moine psammite
Definition of Lower Boundary: At the type section, an erosional contact on Glaciofluvial outwash of the Main Late Devensian Glaciation; elsewhere mapping indicates unconformable contact on Old Red Sandstone bedrock. The till also interdigitates with the lower parts of the Hempriggs Sand Member locally.
Definition of Upper Boundary: Generally the base of the Hempriggs Sand Member, but the latter may also interdigitate with the East Grange Till Member locally.
Thickness: At least 2.5m thick at its type section; mapping indicates that the unit may reach 3 to 4m in thickness locally.
Geographical Limits: Deposit occurs within a discontinuous curvilinear ridge that extends northwestwards from 2.6km east of the centre of Forres, a distance of 8.5km to Easter Coltfield [NJ 1202 6440] and isolated mounds east of Forres. All exposures lie within the SW corner of Scotland Sheet 95 (Elgin).
Parent Unit: Grange Hill Sand Formation (GRHS)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Type section of the East Grange Till Member; disused clay pit, 560m north of East Grange farm. Red-brown sandy diamicton, at least 2.5m thick, containing dropstone cobbles deforming laminated lenses of silty fine white sand. Particle size and micromorpholgy samples collected from this unit at this locality by BGS staff in September 2008. 
Reference(s):
none recorded or not applicable
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S095