Incised palaeo-channels of the late Middle Pleistocene Thames: age, origins and implications for fluvial palaeogeography and sea-level reconstruction in the southern North Sea basin

The sedimentary sequence on the shelf of the southern North Sea records Quaternary climatic changes in two ways. They are indicated directly by moraine and glaciofluvial deposits from the Elsterian, Saalian and Weichselian glacial periods when the British and the Scandinavian ice sheets covered parts of the area. An indirect response to the climate is indicated by sea-level changes. Phases of cooling are characterized by regressions and low sea-level stands; phases of warming are indicated by marine transgressions and high sea levels during the Holsteinian, Eemian and Holocene periods. The seismic characteristics of the different lithological units, the sedimentary sequences and their fossil content are described for the offshore area and the adjacent coastal zone. This provides a record of the interaction of sedimentary processes and the palaeogeographic development as a response to climatic changes.

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Holocene coastal lowland evolution: reconstruction of land-sea transitions in response to sea-level changes (Jade Bay, southern North Sea, Germany)

Zeitschrift der Deutschen Gesellschaft für Geowissenschaften ◽

10.1127/zdgg/2017/0105 ◽

2017 ◽

Vol 168 (1) ◽

pp. 21-38

Author(s):

Martina Karle ◽

Manfred Frechen ◽

Achim Wehrmann

Keyword(s):

Sea Level ◽

North Sea ◽

Sea Level Changes ◽

Southern North Sea ◽

Coastal Lowland ◽

Jade Bay

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Holocene relative sea-level data for the East Frisian barrier coast, NW Germany, southern North Sea

Netherlands Journal of Geosciences – Geologie en Mijnbouw ◽

10.1017/njg.2021.11 ◽

2021 ◽

Vol 100 ◽

Cited By ~ 1

Author(s):

Friederike Bungenstock ◽

Holger Freund ◽

Alexander Bartholomä

Keyword(s):

Sea Level ◽

North Sea ◽

Level Curve ◽

Relative Sea Level ◽

Southern North Sea ◽

Isostatic Adjustment ◽

Landscape Reconstruction ◽

Time Period ◽

Level Data ◽

Age Constraints

Abstract Collecting sea-level data from restricted coastal areas is essential for understanding local effects on relative sea level. Here, a revised relative mean sea-level curve for the area of the East Frisian island Langeoog, northwestern Germany, for the time period from 7200 cal BP until Recent is presented. The revision is based on the reinterpretation of previously published and unpublished data following the HOLSEA standardisation of data handling. Altogether 68 sea-level data taken from 32 cores and outcrops from Langeoog, its back-barrier and the adjacent mainland, which have been collected since the 1950s for mapping and landscape reconstruction purposes, are presented. The age constraints, derived from radiocarbon ages of basal peat, intercalated peat and molluscs and optical dating of tidal deposits, were evaluated in terms of the HOLSEA sea-level protocol and their stratigraphic context. For 7200 cal BP until modern times, 30 sea-level index points with different uncertainty ranges were defined. Additionally, a factor of decompaction was estimated for the remaining basal peat samples as well as for the underlying sediments of intercalated peat samples. The comparison of the Langeoog relative sea-level curve with the relative sea-level curve from the western Netherlands shows that the Langeoog curve lies up to 0.80 m lower than the Dutch curve and diverges for the time before 6000 cal BP. Though the offset coincides with the overall predicted trend of glacial-isostatic adjustment, it is less than predicted. Our study provides a useful assessment of legacy data and contributes to an improved sea-level index dataset for the southern North Sea coast.

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