The BGS Lexicon of Named Rock Units — Result Details

Essie Till Formation

Computer Code: ESTI Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Pebbly sandy silty clay diamicton, calcareous, dark bluish grey but mottled orangey brown near top, and dark greenish grey at depth, containing well-dispersed clasts of red granite, quartzite and schistose metasediments, and sparse fragments of shell, red marl, red sandstone and chalk. The unit locally includes rafts of red clayey diamicton and black fossiliferous mudstone. Commonly including a lower unit that is dark reddish brown.
Definition of Lower Boundary: Sharp uncomformable, undulating contact with Hatton Till Formation or bedrock, or gradational, planar, glacitectonic contact with laminated silt and clay of the Ugie Clay Formation. At partial type section NK05SE 1 the unit unconformably overlies unnamed greenish grey sand and gravel, which in turn rests on olive brown diamicton of the Hythie Till Formation.
Definition of Upper Boundary: Generally sharp, erosional with overlying glaciofluvial or alluvial sand and gravel or ground surface.
Thickness: To 10m.
Geographical Limits: Buchan, northeast Scotland, between Peterhead and Fraserburgh, on sheets 97 and 87E.
Parent Unit: Banffshire Coast and Caithness Glacigenic Subgroup (BCD)
Previous Name(s): Blue-Grey Series (-673)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  BGS-registered borehole NK05SE9, 0.6 to 9.2m depth, drilled at Kinloch Farm, 4km northwest of Peterhead. McMillan and Aitken, 1981. 
Partial Type Section  Pipeline trenches logged by M. Munro (Aberdeen University) at South Essie Farm, near St Fergus, 7 km northwest of Peterhead. Merritt et al. 2003. 
Partial Type Section  BGS registered borehole NK05SE/1, 4.60-12m depth, drilled at St Fergus Moss, 10km northwest of Peterhead. McMillan and Aitken, 1981. 
Reference(s):
McMillan, A A and Aitken, A M. 1981. The sand and gravel resources of the country west of Peterhead, Grampian Region. Description of 1:25 000 sheet NK 04 and parts of NJ 94, 95 and NK 05, 14, and 15. Mineral Assessment Report of the Institute of Geological Sciences, No 58. 
Merritt, J W, Auton, C A, Connell, E R, Hall, A M and Peacock, J D. 2003. The Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, Sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland) 
Hall, A M and Connell, E R. 1991. The glacial deposits of Buchan, northeast Scotland. 129-136 in Ehlers, J, Gibbard, P L and Rose, J (editors), Glacial Deposits in Great Britain and Ireland. (Rotterdam: Balkema.) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable