| Computer Code: |
HNTI |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Devensian Stage (QD)
— Devensian Stage (QD) |
| Lithological Description: |
Typically very stiff, dark brown or purplish brown, stony silty sandy diamicton containing clasts mainly of limestone and dolostone of the Zechstein Group (formerly Magnesian Limestone; mostly Upper Division), Carboniferous lithologies, purple porphyry from the Cheviots and shell fragments. The till is invariably weathered reddish brown at the top, and locally throughout. |
| Definition of Lower Boundary: |
Generally planar, unconformable, subhorizontal boundary with underlying gravel of the Peterlee Sand and Gravel Formation, where the contacts may be sharp or gradational with glacitectonic intercalation. The till locally rests directly on bedrock. |
| Definition of Upper Boundary: |
Commonly a gradational contact with overlying brown pebbly clay with vertical prismatic jointing (Prismatic Clay Member). Lateral interdigitating boundary with the Tyne-Wear Glaciolacustrine Formation to the west. |
| Thickness: |
To 12.2m |
| Geographical Limits: |
Coast of County Durham and southern Northumberland. |
| Parent Unit: |
North Sea Coast Glacigenic Subgroup (NSG)
|
| Previous Name(s): |
Durham Upper Till [Obsolete Name and Code: Use HNTI]
(-321)
|
| Alternative Name(s): |
Horden Member
|
| Stratotypes: |
| Type Section |
Cliff sections in the vicinity of Warren House Gill, 490m south of Horden Point. Smith and Francis, 1967. |
| Reference(s): |
| Huddart, D. 2002. Warren House Gill. 51-56 in Huddart, D and Glasser, N F (editors), Quaternary of Northern England. Geological Conservation Review Series, No.25. [Peterborough: Joint Nature Conservation Committee.] 745pp. |
| Smith, D B, 1994. Geology of the country around Sunderland. Memoir of the British Geological Survey, Sheet 21, (England and Wales). |
| Francis, E A. 1970. Quaternary. 134-152 in Johnson, G A L, Geology of Durham County. [Newcastle: Natural History Society of Northumberland, Durham and Newcastle-upon-Tyne.] 152pp. |
| Smith, D B and Francis, E A. 1967. Geology of the country between Durham and West Hartlepool. Memoir of the Geological Survey of Great Britain, Sheet 27 (England and Wales). |
| Bridgland, D R, Horton, B P, and Innes, J B. 1999. The Quaternary of northeast England. Field Guide. Quaternary Research Assocation, London. |
| Thomas, G S P. 1999. Northern England. 91-98 in Bowen, D Q (Editor), A revised correlation of Quaternary and Neogene deposits in the British Isles. Geological Society Special Report No.23. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
