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| Titel |
New insights into the earliest Quaternary environments in the Central North Sea from 3D seismic |
| VerfasserIn |
Rachel Lamb, Mads Huuse, Margaret Stewart, Simon H. Brocklehurst |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250086847
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| Publikation (Nr.) |
 EGU/EGU2014-782.pdf |
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| Zusammenfassung |
| In the past the transition between an unconformable surface in the south to a conformable
horizon towards the north has made identification and mapping the base-Quaternary in the
central North Sea difficult (Sejrup et al 1991; Gatliff et al 1994). However recent
integration of biostratigraphy, pollen analysis, paleomagnetism and amino acid
analysis in the Dutch and Danish sectors (Rasmussen et al 2005; Kuhlmann et al
2006) has allowed greater confidence in the correlation to the region 3D seismic
datasets and thus has allowed the base-Quaternary to be mapped across the entire
basin.
The base-Quaternary has been mapped using the PGS MegaSurvey dataset from wells in
the Danish Sector along the initially unconformable horizon and down the delta front into the
more conformable basin giving a high degree of confidence in the horizon pick.
The revised base-Quaternary surface reaches a depth of 1248 ms TWT with an
elongate basin shape which is significantly deeper than the traditionally mapped
surface.
Using RMS amplitudes and other seismic attributes the revised base-Quaternary has been
investigated along the horizon and in time slice to interpret the environments of the earliest
Quaternary prior to the onset of glaciation. Combined with analysis of aligned elongate
furrows over 10 km long, 100 m wide and 100 m deep suggest a deep marine environment in
an almost enclosed basin with persistent strong NW-SE bottom currents in the deepest parts.
Pockmarks were formed by the escape of shallow gas on the sides of a small delta in the
eastern part of the basin. The progradation of large deltas from both the north and
south into the basin make up the majority of the deposition of sediment into the
basin.
Key Words: base-Quaternary; seismic interpretation; paleoenvironments
References:
Gatliff, R.W, Richards, P.C, Smith, K, Graham, C.C, McCormac, M, Smith, N.J.P, Long,
D, Cameron, T.D.J, Evans, D, Stevenson, A.G, Bulat, J, Ritchie, J.D, (1994) ‘United
Kingdom offshore regional report: the geology of the central North Sea.’ London: HMSO for
the British Geological Survey
Kuhlmann, G., Langereis C.G., Munsterman, D., van Leeuwen, R.-J., Verreussel,
R., Meulenkamp, J.E., Wong, Th.E., 2006 ‘Intergrated chronostratigraphy of the
Pliocene-Pliestocene interval and its relation to the regional stratigraphical stages in the
Southern North Sea region’ Netherlands Journal of Geosciences 85(1), 29-45
Rasmussen, E.A., Vejb?k O.V., Bidstrup, T., Piasecki, S., Dybkj?r, K., 2005 ‘Late
Cenozoic depositional history of the Danish North Sea Basin: implications for the petroleum
systems in the Kraka, Halfdan, Siri and Nini fields’, Petroleum Geology Conference series 6,
1347-1358
Sejrup, H.P., Aareseth, I., Haflidason, H., 1991 ‘The Quaternary succession in the
northern North Sea’ Marine Geology 101 103-111 |
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