Echteld Formation

NUEC

Formal (Weerts & Busschers 2003).

Heterogeneous. Humic clay with thin discontinuous peat layers, silty and sandy clay intercalated with thin sand layers, very fine to very coarse sand. Local gravel lags, mollusks, diatoms and ostracods. Decreasing grain size and gravel content from east to west.

Anastomosing or meandering fluvial (Rhine-Meuse system), fresh- to brackish water. Including point bar and channel (sandy, fining upward with basal lag), residual channel (clay to medium sand with intercalated peat), natural levee (laminated clay to fine sand), flood basin (organic-rich clay), crevasse splay (very fine to very coarse sand), dike breach (heterogeneous and chaotic), and lake (layered sand and clay, and basal organics) (Berendsen 1982; Weerts 1996; Arnoldussen 2000; Weerts & Busschers 2003; Weerts et al. 2005; Bos 2010).

Sharp contact with fluvial clay (Wijchen Bed, Kreftenheye), sharp contact with coarse to very coarse fluvial sand (Kreftenheye Formation), gradual transition in case of coarse channel deposits. Sharp contact with fine to medium aeolian and local river sand (Boxtel Formation).

Generally, exposed at the surface. Elsewhere, unconformable, mostly sharp contact with clastic tidal deposits (sand and clay with marine shells; Naaldwijk Formation), peat (Hollandveen Member, Nieuwkoop Formation; common interfingering), or eolian sand (Delwijnen Member, Boxtel Formation).

Up to about 15 m in its westernmost reach.

Different architectural elements each have their own unique distribution (Berendsen 1982, 1984a, 1984b; Berendsen & Stouthamer 2001; Weerts & Busschers 2003; Westerhoff & Weerts 2013). Offshore, limited to the entrance to Rotterdam Harbour.

North Sea: not distinguished; UK: not present; GER: equivalent sediments of the Rhine are placed in the 'Jung- Mittel- and Altholozän' (cf. Klostermann 1992; see also Brunnacker 1978; Braun & Thiermann 1981; Klostermann 1989); BEL: not present.

Holocene.

Named after the village of Echteld, southeast of Utrecht.

Rhine deposits of the Betuwe Formation (Doppert et al. 1975). Also includes the Tiel and Gorkum Deposits of the Westland Formation (Doppert et al. 1975).

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

Arnoldussen, S. 2000. Covered with Clay. Man and Landscape during the Late Neolithic up to the Middle Bronze Age in the Dutch central river area, Leiden (unpublished MA thesis), 146 p.

Berendsen, H.J.A. 1982. De genese van het landschap in het zuiden van de provincie Utrecht, een fysisch-geografische studie. Proefschrift, Utrechtse Geografische Studies 25, 255 p.

Berendsen, H.J.A. 1984a. Quantitative analysis of radiocarbon dates of the perimarine area in the Netherlands. Geologie en Mijnbouw, 63, 343-350.

Berendsen, H.J.A. 1984b. Problems of lithostratigraphic classification of Holocene deposits in the perimarine area of the Netherlands. Geologie en Mijnbouw, 63, 351-354.

Berendsen, H.J.A., Stouthamer, E. 2001. Palaeogeographic Development of the Rhine-Meuse Delta, the Netherlands. Koninklijke van Gorcum B.V., 280 p.

Bos, I.J. 2010. Distal delta-plain successions. Architecture and lithofacies of lake fills and organics in the Holocene Rhine-Meuse delta, The Netherlands. Ph.D. Thesis, Utrecht University, 208 p.

Braun, F.J., Thiermann, A. 1981. Geologische Karte von Nordrhein-Westfalen 1:25.000. Erläuterungen zu Blatt 4130 Emmerich. Geologisches Landesamt Nordrhein-Westfalen, Krefeld.

Brunnacker, K. 1978. Der Niederrhein im Holozän. Fortschritte in der Geologie von Rheinland und Westfalen, 339-440.

Doppert, J.W.Chr., Ruegg, G.H.J., Van Staalduinen, C.J., Zagwijn, W.H., Zandstra, J.G. 1975. Formaties van het Kwartair en Boven-Tertiair in Nederland. In: Zagwijn, W.H., Van Staalduinen, C.J. (eds.): Toelichting bij geologische overzichtskaarten van Nederland. Rijks Geologische Dienst, Haarlem, 11-56.

Klostermann, J. 1989. Geologische Karte von Nordrhein-Westfalen 1:25.000. Erläuterungen zu Blatt 4304 Xanten. Mit Beiträgen von J. Nötting, W. Paas & H.-W. Rehagen. Geologisches Landesamt Nordrhein-Westfalen, Krefeld.

Klostermann, J. 1992. Das Quartär der Niederrheinischen Bucht. Geologisches Landesamt Nordrhein-Westfalen, Krefeld, 200 p.

Makaske, B. 1998. Anastomosing rivers. Forms, processes and sediments. Ph.D. Thesis, Utrecht University, 287 p.

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

Weerts, H.J.T. 1996. Complex Confining Layers. Architecture and hydraulic properties of Holocene and Late Weichselian deposits in the fluvial Rhine-Meuse delta, The Netherlands. Ph.D. Thesis, Utrecht University / Netherlands Geographical Studies, 213, 189 p.

Weerts, H.J.T., Westerhoff, W.E., Cleveringa, P., Bierkens, M.F.P., Veldkamp, J.G., Rijsdijk, K.F. 2005. Quaternary geological mapping of the lowlands of The Netherlands, a 21st century perspective. Quaternary International, 133-134, 159-178.

Westerhoff, W.E., Weerts, H.J.T. 2013. Lithostratigraphy. In: Elias, S.A., Mock, C.J. (eds.): Encyclopedia of Quaternary Science. 2nd edition. Elsevier B.V., Amsterdam, 227-242.