Zandvoort Member

NUNAZA

Formal (Weerts 2003).

Grey to brownish grey fine to medium sand, shelly, commonly coarsening upward. Locally, intercalated clay laminae.

Shoreface, nearshore (including breaker bar and runnel), beach and washover.

Commonly, unconformable contact with tidal sand and clay (Wormer Member, Naaldwijk Formation). Elsewhere, mainly offshore, unconformable contact with peat (Hollandveen Member, Nieuwkoop Formation), younger tidal sand and clay (Walcheren Member, Naaldwijk Formation), periglacial sand (Boxtel Formation), river sand and gravel (Kreftenheye Formation), marine sand and clay (Eem Formation), or till (Gieten Member, Drente Formation).

Offshore and on the modern beach, exposed at the surface. Elsewhere, sharp but commonly conformable contact with coastal aeolian sand (Schoorl Member, Naaldwijk Formation) or unconformable contact with clastic tidal sediments (Walcheren Member, Naaldwijk Formation). In former beach plains, locally covered with thin clay and peat (Nieuwkoop Formation).

Up to about 20 m.

Narrow belt along the western and Wadden coasts, between the landwardmost former beach ridges and the base of the modern shoreface, up to 10 km seaward of the present-day coastline. The seaward boundary with the marine Southern Bight Formation is diffuse. The lower shoreface, formed under the influence of shoaling waves, grades into the inner shelf where wave processes have less impact on the seabed. The depth of this transition varies as a function of wave climate, and is typically between 15 and 20 m.

North Sea: not distinguished; UK: British Coastal Deposits Group with the North Denes Formation (McMillan et al. 2011); GER: part of Küstenholozän (Barckhausen et al. 1977; Preuss, 1979); BEL: De Haan Member, Vlaanderen Formation (Gullentops et al. 2001).

Holocene (Northgrippian - Meghalayan).

Named after the coastal village of Zandvoort, west of Amsterdam.

None.

Wim Dubelaar (2018), Sytze van Heteren (2019).

Barckhausen, J., Preuss, H., Streif, H.-J. 1977. Ein lithologisches Ordnungsprinzip für das Küstenholozän und seine Darstellung in Form van Profiltypen. Geologisches Jahrbuch Reihe A 44, 45-77.

Gullentops, F., Bogemans, F., De Moor, G., Paulissen, E., Pissart, A. 2001. Quaternary lithostratigraphic units (Belgium). In: Bultynck, P., Dejonghe, L. (eds.), Guide to a revised lithostratigraphic scale of Belgium, Geologica Belgica, 4/1-2, 153-164.

McMillan, A.A., Hamblin, R.J.O., 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, 343 p.

Preuss, H. 1979. Die Holozäne Entwicklung der Nordseeküste im Gebiet der östlichen Wesermarsch. Geologisches Jahrbuch Reihe A 53, 3-84.

Weerts, H.J.T. 2003. Beschrijving lithostratigrafische eenheid. Nederlands Instituut voor Toegepaste Geowetenschappen TNO. Utrecht.