Seabirds and North Sea oil

The history of large and well-publicized incidents of seabird mortality resulting from oil pollution from tanker accidents (such as the Torrey Canyon in 1967) and from unattributed oil slicks at sea, gave rise to real fears that the development of North Sea oilfields would result in serious mortality and declines in the large populations of seabirds breeding and wintering in and around the North Sea. The oil industry recognized the problem and attempted to minimize pollution risks in all exploration, production and transport operations. Preliminary maps were prepared showing the distribution of vulnerable concentrations of breeding and wintering birds to facilitate contingency planning, and, particularly in Shetland, Orkney and the Moray Firth, extensive and long-term programmes are established to monitor: (1) the numbers of breeding birds; (2) wintering concentrations (particularly of sea ducks); (3) the distribution and abundance of seabirds at sea; (4) the numbers, and percentage oiled, of birds found dead on beaches. The feared increase in oil pollution incidents has not materialized. The few accidents associated with offshore production have had little effect on seabirds. Tanker accidents have been few, but have had large, temporary and local effects (e.g. the Esso Bernicia at Sullom Voe in 1978-79). Breeding seabird populations in the area have increased, although in recent years, in some places, some species may have declined, but these declines cannot be attributed to oil activities in the North Sea. The Beached Bird Survey suggests that chronic oil-induced mortality is at a relatively low level.

Clay Minerals ◽  
1990 ◽  
Vol 25 (4) ◽  
pp. 519-541 ◽  
Author(s):  
M. J. Pearson

AbstractClay mineral abundances in Mesozoic and Tertiary argillaceous strata from 15 exploration wells in the Inner and Outer Moray Firth, Viking Graben and East Shetland Basins of the northern North Sea have been determined in <0·2 µm fractions of cuttings samples. The clay assemblages of more deeply-buried samples cannot be unambiguously related to sedimentary input because of the diagenetic overprint which may account for much of the chlorite and related interstratified minerals. Other sediments, discussed on a regional basis and related to the geological history of the basins, are interpreted in terms of clay mineral provenance and control by climate, tectonic and volcanic activity. The distribution of illite-smectite can often be related to volcanic activity both in the Forties area during the M. Jurassic, and on the NE Atlantic continental margin during the U. Cretaceous-Early Tertiary which affected the North Sea more widely and left a prominent record in the Viking Graben and East Shetland Basin. Kaolinite associated with lignite-bearing sediments in the Outer Moray Firth Basin was probably derived by alteration of volcanic material in lagoonal or deltaic environments. Some U. Jurassic and L. Cretaceous sediments of the Inner Moray Basin are rich in illite-smectite, the origin of which is not clear.


1982 ◽  
Vol 8 ◽  
pp. 9-26
Author(s):  
Claus Andersen ◽  
Jens Christian Olsen ◽  
Olaf Michelsen ◽  
Erik Nygaard

The Central Graben is a broad, complex trough with a long history of differential subsidence. It was probably initiated in the Permian and was controlled by major rifting during the Mesozoic. To the south in the Dutch sector the trough is divided into two parts. From here it passes northwards and divides the southern North Sea Basin into the Anglo-Dutch Basin and the Northwest German Basin. It also separates the Mid North Sea High from the Ringkøbing-Fyn High. These highs form broad, east-west trending, relative stable ridges. The further continuation of the Central Graben is to the northwest, towards the centre of the North Sea, where it passes into the Viking Graben and the Moray Firth Basin at about 58° N. Where the Central Graben divides the two major highs, there is an elongate central narrow horst, the Dogger High, which is the southernmost of a row of mid-Graben highs. Both sides of the Graben are clearly defined by normal rotational faults that were intermittently active from Triassic to Early Cretaceous times.


2008 ◽  
Author(s):  
Kevin Arthur Bourassa ◽  
Tove Husby ◽  
Rick Deuane Watts ◽  
Dale Oveson ◽  
Tommy M. Warren ◽  
...  

Author(s):  
P. E. P. Norton

SynopsisThis is a brief review intended to supply bases for prediction of future changes in the North Sea Benthos. It surveys long-term changes which are affecting the benthos. Any prediction must take into account change in temperature, depth, bottom type, tidal patterns, current patterns and zoogeography of the sea and the history of these is briefly touched on from late Tertiary times up to the present. From a prediction of changes in the benthos, certain information concerning the pelagic and planktonic biota could also be derived.


1977 ◽  
Vol 1977 (1) ◽  
pp. 45-52 ◽  
Author(s):  
D. R. Blaikley ◽  
G. F. L. Dietzel ◽  
A. W. Glass ◽  
P. J. van Kleef

ABSTRACT The reasons are introduced for the development of a simulator sufficiently simple to enable weather data normally acquired for E & P operations to be used. “SLIKTRAK,” developed by Shell, applies a slick description and combat concept, developed within the E & P Forum for well blowouts in the North Sea, but applicable to other areas. This concept includes costs for cleanup, damages and the effect of phenomena such as evaporation and natural dispersion. These factors are based on industry experience and vary primarily with sea conditions. The computer programme simulates the continued creation of an oil spill and applies weather data to predict movements of each day's spillage for successive days at sea and quantities of oil left after each day until the oil either disappears or reaches a coastline. Cumulative probability curves for the oil volumes cleaned up, oil arriving at specified shores, total costs, etc., are produced by random selection of input variables such as well location, weather data, the possibility of well bridging etc., and repetition of simulated spill incidents over a large number of cycles. Trace-plots of individual spills may also be generated. In association with the E & P Forum's position as technical advisers to the North West European Civil Liability Convention for Oil Pollution Damage from Offshore Operations, a study based on the North Sea areas has been made. These results and further developments of the program are discussed.


1991 ◽  
Author(s):  
Gary Hampson ◽  
Terje Hansen ◽  
H. Jakubowicz ◽  
John V. Kingston

2008 ◽  
Vol 65 (8) ◽  
pp. 1392-1397 ◽  
Author(s):  
Peter Heslenfeld ◽  
E. Lisette Enserink

Abstract Heslenfeld, P., and Enserink, E. L. 2008. OSPAR Ecological Quality Objectives: the utility of health indicators for the North Sea. – ICES Journal of Marine Science, 65: 1392–1397. Committed to the ecosystem approach to management, OSPAR has accumulated 15 years of experience in developing a conceptual framework for ecological indicators and objectives, and in applying the framework to the North Sea as a test case. These Ecological Quality Objectives (EcoQOs) have become a model for the implementation of the new European Marine Strategy Framework Directive. We describe the history of EcoQO development, its current status, and future needs. We also present our positive and negative experiences in developing the approach, and conclude that regional sea conventions and marine research institutes in Europe should join forces to accelerate the development of ecosystem indicators and objectives, using existing concepts.


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.


2014 ◽  
Vol 35 (2) ◽  
pp. 200-219
Author(s):  
Eike-Christian Heine

The Kiel Canal (built between 1886 and 1895) connects the North Sea and the Baltic for seagoing vessels, yet, being 100 km long, about 10 m deep and 100 m wide, it also divides a landscape. This finding is the starting point for analysing the effects of infrastructure that facilitates communication and exchange but also produces obstructions and rivalries. This article explores the ambiguous effects this piece of infrastructure had on politics, technology, labour, trade and military strategy. The ‘deep ditch’ also had severe environmental consequences that were palpable until well into the twentieth century. By considering both the ‘positive’ and the ‘negative’ of the waterway, the narrative of ‘connect-and-divide’ avoids the still-too-often told affirmative story of transport infrastructure. Instead, it and opens the outlook to a multi-faceted history of transport infrastructures.


Sign in / Sign up

Export Citation Format

Share Document