The BGS Lexicon of Named Rock Units — Result Details

Weybourne Town Till Member

Computer Code: WTTI Preferred Map Code: notEntered
Status Code: Full
Age range: Pleistocene Epoch (QP) — Pleistocene Epoch (QP)
Lithological Description: The Weybourne Town Till Member consists of a highly calcareous silt and chalk-rich matrix supported diamicton. It is generally massive in structure, but locally, such as at the unit's stratotype locality, the diamicton is highly stratified, consisting of highly attenuated and deformed inclusions of pre-existing till (Bacton Green Till Member).
Definition of Lower Boundary: The lower boundary of the chalky diamicton facies of the Weybourne Town Till Member rests upon either the Wroxham Crag Formation or the Bacton Green Till Member. In the case of the Wroxham Crag Formation, the boundary is sharp and planar and in places resembles a plane of decollement, with till resting upon sand and gravel. In the latter case where it overlies the Bacton Green Till Member (brown sandy diamicton), the Bacton Green Till has been folded and incorporated into the Weybourne Town Till in a series of highly attenuated shear structures.
Definition of Upper Boundary: The Weybourne Town Till Member is overlain and truncated by the sands and gravels of the Briton's Lane Formation.
Thickness: Locally to 6m
Geographical Limits: The Weybourne Town Till Member crops out in the Weybourne, Hanworth and Trimingham areas of north Norfolk. No stratigraphical link is made with 'Marly Drift' to the west of the Glaven Valley.
Parent Unit: Sheringham Cliffs Formation (SMCL)
Previous Name(s): Marly Drift [Obsolete Name and Code: Use WTTI] (-3774)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Weybourne Town Pit on the eastern edge of Weybourne, north Norfolk. At this locality, the till can be seen to overlie preglacial sands of the Wroxham Crag Formation. Fish et al., 2000. 
Reference(s):
McMillan, A A, Hamblin, R J O, and Merritt, J W. 2011. A lithostratigraphical framework for onshore Quaternary and Neogene (Tertiary) superficial deposits of Great Britain and the Isle of Man. British Geological Survey Research Report, RR/10/03. 343pp. 
Lee, J R, Booth, S J, Hamblin, R J O, Jarrow, A M, Kessler, H, Moorlock, B S P, Morigi, A N, Palmer, A, Riding, J B and Rose, J. 2004. A new stratigraphy for the glacial deposits around Lowestoft, Great Yarmouth, North Walsingham and Cromer, East Anglia, UK. Bulletin of the Geological Society of Norfolk, Vol.53, 3-60. 
Straw, A. 1965. A reassessment of the Chalky Boulder Clay or Marly Drift of north Norfolk. Zeitschrift fur Geomorphologie, Vol.9, 209-221. 
Fish, P R, Whiteman, C A, Moorlock, B S P, Hamblin, R J O and Wilkinson, I P. 2000. The glacial geology of the Weybourne area, north Norfolk: a new approach. Bulletin of the Geological Society of Norfolk, Vol.50, 21-45. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable