Hellevoetsluis Formation

Code
DCDH
Status
Formal (Van Adrichem Boogaert & Kouwe 1995).
Lithological description

Succession of interbedded 1 to 15 m thick sandstone beds and silty to sandy, carbonaceous mudstones containing occasional coal seams. Sands are predominantly grey or white, fine- to coarse-grained, well- to moderately-sorted and subangular and occur in sheets and channel fills, locally stacked up to 30 m thick, with frequent metre-scale mudstone intercalations.
Mudstone intervals are predominantly greenish-grey or beige, frequently with purple or red-brown horizons in the their upper parts. Coal seams are rare, associated with grey claystone intervals of 5 to 55 m thick.

Depositional setting

Amalgamated braided fluvial channel fills, with overbank deposits (crevasses, sheet floods).
Poorly- or fairly-drained flood-plains and with local swamps. Sandstone-dominated and mudstone-dominated intervals can be correlated on a local to regional scale, implying a depositional cyclicity.

Definition of lower boundary

Contact with the underlying Maurits Formation is marked by the incursion of thick, argillaceous matrix-poor sandstone beds, commonly in combination with a decrease in the frequency of coal seams.

Definition of upper boundary

Marked by a transition towards thick, greenish-grey or orange-red mudstones with fewer intercalated sheet sandstones, typical for the overlying Strijen Formation. The boundary is defined at the base of the first mudstone-dominated interval of more than 60 m thick. This diachronous change occurred earlier in the centre of the basin than along its margins.

Thickness indication
Up to 414 m.
Geographical distribution
Regional correlation
UK: ? / GER: ? / BEL: ?.
Age
Moscovian.
Holostratotype
Depth (thickness) AH:
2957 - 3214 m (257 m)
Parastratotype
Depth (thickness) AH:
1725 - 1880 m (155 m)
Parastratotype
Depth (thickness) AH:
3766 - 3881 m (115 m)
Parastratotype
Depth (thickness) AH:
2950 - 3033 m (83 m)
Parastratotype
Depth (thickness) AH:
2765 - 3023 m (258 m)
Parastratotype
Depth (thickness) AH:
3355 - 3516 m (161 m)
Origin of name
Named after the Dutch town of Hellevoetsluis in the southwest of the province of Zuid-Holland, where the type well is located.
Previous name(s)
Informal reffered to by some oil companies as the 'Twente Sandstone'.
Reviewed by (date)
Tom van Hoof (2017).
References
Van Adrichem Boogaert, H.A. & Kouwe, W.F.P. 1995. Stratigraphic nomenclature of The Netherlands, revision and update by RGD and NOGEPA, Section C, Silesian. Mededelingen Rijks Geologische Dienst, 50, 1-40.
Cite as
TNO-GDN ([YEAR]). Hellevoetsluis Formation. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from http://www.dinoloket.nl/en/stratigraphic-nomenclature/hellevoetsluis-formation.