Breeveertien Formation SLDB

 

Premise Formation defined by van Adrichem Boogaert & Kouwe (1993). Contains deposits, which would formerly have been placed in the Delfland Formation occurring in the Broad Fourteens Basin.
Derivatio nominis Named after the Breeveertien (= Broad Fourteens) fishing grounds, where the type area is situated.
Type section Location map See figure (pdf)
  Well K15-01 (pdf)
  Location N 53°13’28.2
E 03°53’47.6
  Depth 1559 to 2270 m
  Length 711 m along hole
Definition Interval of predominantly grey-brown, carbonaceous, but also variegated or red, silty claystones, fine- to medium-grained sandstones with bed thicknesses up to several metres, and coarse-grained, thick-bedded sandstones. Coal/lignite beds are virtually absent. Dispersed lignitic matter, siderite spherulites and concretions are common. Cored sections show extensive mottling of the variegated claystones. Locally, intercalated calcareous clay- stones and a few nodular evaporitic beds occur. Sands occur in sheets, isolated channels, or stacked valley fills.
Upper Boundary The Rijnland Group (mostly Vlieland Sandstone Formation) unconformably overlies this formation if a Late Kimmerian II unconformity is developed. At other localities, the two formations partially interfinger (Kotter Member and Helder Member of Vlieland Sandstone Formation, and Helm Member of Breeveertien Formation). In inverted settings the formation is unconformably covered by the Chalk Group or Lower North Sea Group.
Lower Boundary In the central part of the Broad Fourteens Basin this formation unconformably (Late Kimmerian I phase) overlies the Altena Group (marine claystones and sandy carbonates of the Aalburg Formation, Werkendam Formation or Brabant Formation). Along the margins of the basin it rests on deposits of Triassic or older age (mainly red beds, carbonates and evaporites)
Distribution The Breeveertien Formation is restricted to the Broad Fourteens Basin.
Age The formation is of Early Kimmeridgian - Valanginian age (partly on the basis of datings from the Rijnland Group). Dating the Breeveertien Formation remains difficult because of the restricted occurrence of dinoflagellates. Some members can be dated more accurately (see fol-lowing sections). At certain levels stratigraphically significant ostracods may be abundant. One of the most characteristic shifts in palynology is seen at the Portlandian-Ryazanian boundary. Classopollis, characteristically dominant in the Portlandian, shows a remarkable drop in abundance, and is replaced by Cicatricosisporites in the Ryazanian (van Amerom, Herngreen and Romein (1976) ; Herngreen et al (1980) ). This is seen as the reflection of a climatic change from dryer to more humid conditions (Herngreen, pers. comm.). In the Breeveertien Formation this transition is found in the Driehuis Mottled Claystone Member or equivalent Fourteens Claystone Member
Depositional Setting Sands were deposited both as stacked and isolated channels, and as lacustrine-deltas and crevasse-splays in a flood-plain setting. Fines were laid down in lakes and on flood-plains. Mottling and concretions reflect soil formation caused by fluctuating groundwater-tables and long periods of non-deposition. The abundant plant material indicate periods of widespread vegetation.
Sequence Stratigraphy The Breeveertien Formation corresponds to Haq (1988) ’s sequences LZA 4.4 to LZB 2.2. The individual members are more confined in time and space. The correlation between lithofacies and systems tract is discussed under the Schieland Group.
Subdivision  
  In NAM and RGD (1980) the ’Delfland Group’ was subdivided into three formations: the Upper and Lower Delfland Formations, separated by the Fourteens Claystone Formation. The transfer of the ’Delfland Group’ in the Broad Fourteens Basin to the Breeveertien Formation has lowered the status of the previous subdivision to members. The former ’Upper Delfland Formation’ has been further subdivided. Except for the well-established Fourteens Clay, new names have been chosen for the members.
  SL Schieland Group
  SLD Delfland Subgroup
  SLDB Breeveertien Formation
  SLDBH Helm Member
  SLDBN Neomiodon Claystone Member
  SLDBB Bloemendaal Member
  SLDBM Driehuis Mottled Claystone Member
  SLDBS Santpoort Member
  SLDBC Fourteens Claystone Member
  SLDBA Aerdenhout Formation
  The Aerdenhout Member is the new equivalent of the former Lower Delfland Formation The former Upper Delfland Formation (in K15) more or less equates to the Bloemendaal Member and Neomiodon Claystone Member of K18-P03. The Santpoort and Driehuis Mottled Claystone Member of K18-P03 are lateral equivalents of the upper parts of the Fourteens Claystone Member in Q01 (southwest) and K15 (northeast).
References See References Upper Jurassic/ Lower Cretaceous

Van Adrichem Boogaert, H.A. & Kouwe, W.F.P., 1993-1997. [Stratigraphic unit]. In: Stratigraphic Nomenclature of the Netherlands.
Retrieved [Datum] from [url].