Quantitative analysis of submarine fans in the Tertiary of the North Sea Basin

Abstract. Based upon a combination of biometric and quantitative analysis on the Arkhangelskiella cymbiformis group, six additional datums were obtained in the Campanian to Maastrichtian interval of the North Sea area. These datums are in ascending order: 1. first common to abundance occurrence of A cymbiformis (Var. NT); 2. last common to abundance occurrence of A. cymbiformis (Var. NT); 3. first common to abundant occurrence of A. cymbiformis (var. N); 4. first common to abundant occurrence of A. cymbiformis (Var. W); 5. last common to abundant occurrence of A. cymbiformis (Var. N); and 7. last common to abundant occurrence of A. cymbiformis (Var. W). The width of the shield is taken as a main criterion for biometric analysis.

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Lithology and subsidence in the North Sea

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1982.0027 ◽

1982 ◽

Vol 305 (1489) ◽

pp. 85-99 ◽

Cited By ~ 4

Keyword(s):

North Sea ◽

Late Jurassic ◽

Late Carboniferous ◽

Delta Front ◽

Submarine Fans ◽

The North ◽

Late Tertiary ◽

Moray Firth ◽

Deltaic Sedimentation ◽

The North Sea

The North Sea sedimentary basin has developed on the northwestern margin of the European tectonic plate and contains an almost continuous record of epeirogenic marine and deltaic sedimentation from Carboniferous to Recent times. The subsidence required to accommodate the pile of sediment deposited, which in places exceeds 12 km, has been brought about at various times and in various places by differing geodynamical processes. As a result the types of sedimentary rocks deposited vary widely both in time and space, but the nature of the mechanism is reflected in the sedimentary type deposited. The following broad generalizations can be made. The late Carboniferous was a period of deltaic sedimentation during which eustatic changes in sea level or local variations in subsidence rates are reflected in the typical Coal Measures swamp deposits. Late Carboniferous - early Permian times saw the silting up of this basin, and in an arid climate aeolian sands were deposited grading laterally to sabkha shales and evaporites. The Permian culminated in a series of widespread marine incursions during which repetitive evaporites were deposited. Triassic times were marked by a period of major rifting and the deposition of thick sequences of continental elastics in the north, while widespread marine sedimentation persisted in southern areas. Jurassic times saw the re-establishment of marine to deltaic deposition in a series of basins possibly controlled in their distribution by the Triassic fault systems. Late Jurassic deposits were laid down in a sea whose bathymetry reflected the structure of the underlying horsts and grabens inherited from Triassic times, and towards the close of the Jurassic the bottom waters at least of this sea become increasingly stagnant. Sands deposited during the late Jurassic were deposited as near-shore marine bars, beach sands, and proximal and distal submarine fans. Triassic to early Cretaceous deposition was concentrated in the areas now occupied by the main grabens of the North Sea, i.e. the Viking, Central and Moray - Witch Ground grabens. Subsequent deposition in late Cretaceous to Tertiary times took place in a more widely subsiding area, resulting in progressive onlap onto the surrounding basin margins. Deposition within this broadly subsiding and relatively unfaulted basin is characterized by chalky limestones in southern areas, giving way laterally to shales and minor sands to the north. During early Tertiary times a large delta was formed in the area beneath the present Moray Firth, and from this delta a supply of sand was fed into submarine fans to the northeast and southeast of the delta front. Late Tertiary deposition is largely represented by a monotonous sequence of marine shales.

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The First Waves of Internationalization: A Comparison of Early Modern North Sea and Nineteenth-Century Transatlantic Labour Migrations

Maritime Transport and Migration ◽

10.5949/liverpool/9780973893434.003.0002 ◽

2007 ◽

Author(s):

Jelle van Lottum

Keyword(s):

Nineteenth Century ◽

Quantitative Analysis ◽

North Sea ◽

Mobility Patterns ◽

Urban Populations ◽

Migration Patterns ◽

Chain Migration ◽

The North ◽

Mass Migration ◽

The North Sea

This chapter argues that prior to the mass migration and globalisation of the nineteenth century, an earlier era of mass migration can be identified in the North Sea region between 1600 and 1950. It offers a quantitative analysis of Northwest Europe’s first major waves of internationalisation. It provides and analyses emigration rates and mobility patterns throughout the period, and seeks to determine the causes of increased migration within the region spanning Scotland, England, the Netherlands, Germany, Denmark, Sweden, and Norway. It identifies two main waves of migration, occurring between 1550-1800 and 1850-1950 respectively. In exploring migration patterns, it defines four phases of movement: introductory, growth, saturation, and regression. Chain migration, industrialisation, the growth of urban populations, and the needs of the labour market are all considered, before concluding that the populace of the pre-industrialisation North Sea region was fairly mobile, linked to the supply of labour across the region, and statistically similar to the age of mass migration that followed later.

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