Kreekrak Formation

Code
NUKK
Status
Formal (Kiden & Gouw 2010).
Lithological description

Heterogeneous. Greyish brown to brown organic clay, massively or horizontally bedded, with local sand laminae. Local shells and shell debris, common wood and plant fragments. Subordinate greenish brown to black gyttja, peat, and silty or clayey very fine to medium sand.

Depositional setting

Predominantly meandering fluvial (Scheldt), including channel (sand), abandoned channel (gyttja, local clayey peat, humic clay, fine sand), and floodplain (humic clay). Also, estuarine (clayey sand with peat layers) and lacustrine.

Definition of lower boundary

Typically sharp and partly erosive contact with organics (Basisveen Bed, Nieuwkoop Formation, clastic tidal deposits (Wormer and Walcheren Members, Naaldwijk Formation), periglacial sand and loam (Boxtel Formation), older Scheldt sand (Koewacht Formation) or coarse fluvial and estuarine Rhine sand (Waalre Formation). Locally diffuse transition where interfingering with the Nieuwkoop (Hollandveen Member) and Naaldwijk Formations.

Definition of upper boundary

Typically sharp and partly erosive contact with organics (Basisveen Bed, Nieuwkoop Formation, clastic tidal deposits (Wormer and Walcheren Members, Naaldwijk Formation), periglacial sand and loam (Boxtel Formation), older Scheldt sand (Koewacht Formation) or coarse fluvial and estuarine Rhine sand (Waalre Formation). Locally diffuse transition where interfingering with the Nieuwkoop (Hollandveen Member) and Naaldwijk Formations.

Thickness indication
Between 0.1 and 8 m, averaging 1 - 2 m. Highly variable over short distances.
Geographical distribution
Regional correlation
North Sea: not present; UK: not present; GER: not present; BEL: Arenberg Formation (Gullentops et al. 2001).
Age
Late Pleistocene (Younger Dryas) - 500 AD (Vos 1992; Bos et al. 2005).
Holostratotype
Well:
Depth (thickness) AH:
10.12 - 14.34 m (4.22 m) below land surface
Parastratotype
Well:
Depth (thickness) AH:
1.05 - 3.05 m (2.00 m) below land surface
Origin of name
Named after a small tidal channel connecting two branches of the river Scheldt (presently known as the Western and Eastern Scheldt.
Previous name(s)
Schelde-1, -2, -3 and -4 deposits (Vos 1992). Upper Schelde deposits (Sc.b) and Lower Schelde deposits (Sc.o) (Vos & Van Heeringen 1997).
Reviewed by (date)
Wim Dubelaar (2018), Sytze van Heteren (2019).
References
Bos, J.A.A., Huisman, D.J., Kiden, P., Hoek, W.Z., Van Geel, B. 2005. Early Holocene environmental change in the Kreekrak area (Zeeland, SW-Netherlands): a multi-proxy analysis. Palaeogeography, Palaoeclimatology, Palaeoecology 227, 259-289.
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.
Kiden, P., Gouw, M. 2010. Beschrijving lithostratigrafische eenheid. Nederlands Instituut voor Toegepaste Geowetenschappen TNO. Utrecht.
Vos, P.C., Van Heeringen, R.M. 1997. Holocene geology and occupation history of the province of Zeeland. Mededelingen Nederlands Instituut voor Toegepaste Geowetenschappen TNO 59, NITG-TNO, Utrecht, 5-109.
Vos, P.C. 1992. Toelichting kaartblad 43/49 West en 49 Oost - Concept toelichting 43/49 West: Holocene deel, RGD-Rapport 1454. Rijks Geologische Dienst, Haarlem, 41 p.
Cite as
TNO-GDN ([YEAR]). Kreekrak Formation. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from https://www.dinoloket.nl/en/stratigraphic-nomenclature/kreekrak-formation.