| 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 |
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| Depth | 3065 to 3246 m | ||
| Length | 181 m along hole | ||
| Additional section | Location map | See figure (pdf) | |
| Well | F18-02 (pdf) | ||
| Location | N 53°56’55.4 E 04°40’22.0 |
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| Depth | 2182 to 2426 m | ||
| Length | 244 m along hole | ||
| Well | F15-A-01 (formerly F15-04) (pdf) | ||
| Location | N 54°12’58.6 E 04°49’42.4 |
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| Depth | 2598 to 2692 m | ||
| Length | 94 m along hole | ||
| Definition | Well sorted, greenish-grey, argillaceous, glauconitic sandstone. Strongly bioturbated, locally pyritic and lignitic. | ||
| Upper Boundary | The upper boundary, with the Spiculite Member, is marked by a funnel-shaped GR-log pattern, resulting from the upward-decreasing clay content. To the south this change can be seen better on a porosity log. | ||
| Lower Boundary | The lower contact, with the Scruff Basal Sandstone Member, is marked by a downward drop in GR readings (bell-shape). To the south (proximal) this change may be clearer on a porosity log. When the Kimmeridge Clay Formation is present beneath this member, an increase in clay content (GR-log) is seen. In the eastern Terschelling Basin (see pdf) (seen in F15-A-01) the Scruff Argillaceous Member rests directly upon the Oyster Ground Claystone Member. No angular unconformity is seen, but stratigraphic data suggest a time gap between the two, representing the time of deposition of the Scruff Basal Sandstone Member. | ||
| Distribution | The Scruff Argillaceous Member is restricted to the southern Dutch Central Graben (southern F-quadrant) and Terschelling Basin (see pdf) areas. It is not recognised in the northern Dutch Central Graben (F03), and has been eroded below the unconformity underneath the Stortemelk Member in the southern rim zone of the Central Graben (L02-L05). The Kimmeridge Clay Formation forms a lateral equivalent to the north (northern Central Graben), and locally to the south (L03-01) | ||
| Age | An Early Portlandian to Early Ryazanian age is inferred (see Herngreen and Wong (1989) ). Late Early Portlandian markers are Dingodinium spinosum, Egmontodinium polyplacophorum, E. expiratum, Gochteodinia villosa, G. virgula (kerberus- and anguiformis-zones, Herngreen and Wong (1989) ). Older Early Portlandian ages are indicated by Glossodinium dimorphum, Gochteodinia mutabilis, and Muderongia sp.A Herngreen and Wong (1989) . Late Portlandian forms are Gochteodinia virgula, Batioladini-um sp. Ryazanian dinoflagellate forms comprise Canno-sphaeropsis thula and Gochteodinia villosa, and their sporomorph assemblages are characterised by an abundance of Cicatricosisporites spp. | ||
| Depositional Setting | These sands were deposited in a middle- to lower-shoreface marine setting. The lithofacies suggests reworking and deposition as storm-sand sheets from offshore- shoals. Compared to the other members the more argillaceous nature of the member suggests greater water-depths. The overall funnel-shaped GR-log pattern sug-gests coastal progradation. | ||
| Sequence Stratigraphy | The deposition of the Scruff Argillaceous Member spans most of the sequences LZB 1.2 (Highstand systems tracts) - 1.5 (Early Highstand systems tract). Individual sequence boundaries that fall in this interval are often inconspicuous. | ||
| 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]. |
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