Scruff Basal Sandstone Member SGGSB

 

Premise Member defined by van Adrichem Boogaert & Kouwe (1993).
Derivatio nominis Named after the offshore Upper Scruff Bank near well F03-03.
Type section Location map See figure (pdf)
  Well F15-02 (pdf)
  Location N 54°14’18.5
E 04°50’44.9
  Depth 3246 to 3276 m
  Length 30 m along hole
Definition Moderately to well-sorted, greenish-grey non-argilla-ceous, calcite-cemented, glauconitic sandstone, with fine to medium sand (up to gravel) grain sizes. The member is usually bioturbated locally shell debris is found.
Upper Boundary The upper boundary, with the Argillaceous Member or Kim-meridge Clay Formation, is marked by a gradual upward increase in GR-readings (bell shape).
Lower Boundary The lower boundary, with the Oyster Ground Claystone Member (Friese Front Formation), is marked by a sharp downward increase in GR readings, although a gentle funnel shape can be observed in the uppermost parts of the Oyster Ground Claystone Member in some wells.
Distribution Southern Dutch Central Graben, southern F-quadrant. In basin-margin settings (northern L-quadrant, eastern Terschelling Basin (see pdf) (F15-A-01) the Basal Sandstone Member was not deposited or has been eroded. The member is mutually exclusive with the Terschelling Sandstone of the Friese Front Formation. It is a lateral equivalent of the Terschelling Sandstone Member (Friese Front Formation), which constitutes a basin-fringe equivalent in the northern L-quadrant.
Age An earliest Portlandian(-latest Kimmeridgian) age is in-ferred from Ctenidodinium culmulum, C. panneum, Glos-sodinium dimorphum, Gochteodinia mutabilis and Seno-niasphaera jurassica. Sporomorphs are Cicatricosispo-rites spp. and Parvisaccites radiatus (Herngreen and Wong (1989) ).
Depositional Setting These sands were deposited in a transgressive shoreface setting. In the northern L-quadrant they grade into coast-al-barrier and tidal-inlet deposits of the Terschelling Sandstone Member The lithofacies suggests reworking- and winnowing-controlled sheet-sand deposition. Glauconite and fossils attest to the marine, reworked nature of the deposit.
Sequence Stratigraphy The Basal Sandstone Scruff Member reflects the Transgres-sive systems tract of Haq (1988) ’s sequence LZB 1.2.
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].