The BGS Lexicon of Named Rock Units — Result Details

Mundesley Sand Member

Computer Code: MYSA Preferred Map Code: notEntered
Status Code: Full
Age range: Pleistocene Epoch (QP) — Pleistocene Epoch (QP)
Lithological Description: Dull yellow-orange to dull yellowish brown stratified silty sands with a high abundance of detrital chalk in the lower horizons, and opaque heavy minerals. Typical bedding structures include planar cross-bedding, horizontal bedding, massive beds, climbing ripples and convolute bedding.
Definition of Lower Boundary: Erosional lower contact with the chalky diamicton of the Walcott Till Member. The upper surface of the latter is slightly undulatory in form with the topographic lows filled by chalk-rich gravel before passing up into the silty sands of the Mundesley Sand Member.
Definition of Upper Boundary: The upper boundary of the Mundesley Sand Member is variable. Where the deposit is overlain by the Bacton Green Till, such as between Bacton and Mundesley, the contact is gradational and marked by a zone of horizontally-bedded sands and diamicton. Alternatively, where the Ivy Farm Laminated Silt Member overlies the Mundesley Sand Member, the boundary is unconformable (?tectonic).
Thickness: The Mundesley Sand Member reaches a maximum observed thickness of 9m in its stratotype area.
Geographical Limits: The Mundesley Sand Member crops out between Bacton and Sidestrand.
Parent Unit: Sheringham Cliffs Formation (SMCL)
Previous Name(s): Mundesley Sands [Obsolete Name and Code: Use MYSA] (-1080)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Coastal cliff section approximately 1km southeast of Mundesley Coastguard Station and northwest of Bacton Gas Terminal. Sections at this locality show the Mundesley Sand Member sandwiched between the Walcott Till and Bacton Green Till members. Banham, 1966. 
Reference(s):
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. 
Banham, P H. 1968. A preliminary note on the Pleistocene stratigraphy of northeast Norfolk. Proceedings of the Geologists' Association, Vol. 79, 507-512. 
Lunkka, J P. 1994. Sedimentation and lithostratigraphy of the North Sea Drift and Lowestoft Till Formations in the coastal cliffs of northeast Norfolk, England. Journal of Quaternary Science, Vol. 9, 203-233. 
Banham, P H. 1966. The significance of till pebble lineations and their relation to folds in two Pleistocene tills at Mundesley, Norfolk. Proceedings of the Geologists' Association, Vol. 77, 469-474. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable