scholarly journals Protecting the North Sea: Cleaver Bank.

2020 ◽  
Author(s):  
Oceana ◽  
Helena Álvarez ◽  
Allison L. Perry ◽  
Jorge Blanco ◽  
Cecilie Petersen ◽  
...  
Keyword(s):  
North Sea ◽  
Ecological Integrity ◽  
Current Management ◽  
Entire Area ◽  
Marine Life ◽  
The North ◽  
Management Measures ◽  
The North Sea ◽  
The Uk ◽  
Benthic Ecosystems

Cleaver Bank represents the largest area of hard substrate in the Dutch North Sea, and its biodiversity importance has been repeatedly recognised. The combination of oceanographic and geological patterns found in the area (e.g., depth, low currents and light penetration) makes Cleaver Bank a unique enclave of marine life in the Dutch EEZ. Thus, it has already been designated under various figures of protection (see Box 4). However, current management measures for these areas fail to secure the preservation of the area’s fragile combination of features. Bearing in mind that the disappearance of the former rocky banks in Dutch waters was caused by their direct removal in bottom trawls, and the threat that fishing activities pose to the fragile and varied seabed of Cleaver Bank, Oceana proposes that the entire area of Klaverbank SAC should be closed to all type of bottom-contacting gears. Continued bottom-contact fishing in Klaverbankrepresents a clear threat to the fragile benthic ecosystems found in the area. On the UK side, Oceana’s findings have further confirmed that Cleaver Bank as a whole (both the Dutch and UK sides) is characterised by very similar habitats and communities. Oceana urges the UK government to carry out more detailed habitat mapping, in order to better identify the range of features present, and determine which conservation and management measures are needed to preserve and restore the ecological integrity of Cleaver Bank.

scholarly journals Protecting the North Sea: New research for biodiversity recovery.

2020 ◽  
Author(s):  
Oceana ◽  
Helena Álvarez ◽  
Allison L. Perry ◽  
Jorge Blanco ◽  
Silvia Garcia ◽  
...  
Keyword(s):  
North Sea ◽  
Marine Biodiversity ◽  
Legal Requirements ◽  
Marine Life ◽  
The North ◽  
Marine Habitats ◽  
Wide Range ◽  
The Face ◽  
The North Sea ◽  
New Research

To help fill gaps in knowledge about marine biodiversity in the North Sea, Oceana carried out two eight week research expeditions, in 2016 and 2017. Oceana’s surveys documented a wide range of habitats and species that are considered priorities for conservation, under national, EU, and international frameworks that recognise them as threatened and/or establish legal requirements for their protection.Oceana’s research has underscored the fact that much remains to be discovered about marine life on the seabed of the North Sea. Continued research is critical for informing efforts to recover biodiversity, an urgent priority in the face of the multiple, intense pressures facing the North Sea’s marine habitats and species.

Towards a vulnerability assessment of the UK and northern European coasts: the role of regional climate variability

2005 ◽  
Vol 363 (1831) ◽  
pp. 1329-1358 ◽  
Author(s):  
M.N Tsimplis ◽  
D.K Woolf ◽  
T.J Osborn ◽  
S Wakelin ◽  
J Wolf ◽  
...  
Keyword(s):  
Sea Level ◽  
Wave Height ◽  
North Sea ◽  
Positive Response ◽  
Sea Level Change ◽  
Empirical Relationships ◽  
Level Change ◽  
The North ◽  
The North Sea ◽  
The Uk

Within the framework of a Tyndall Centre research project, sea level and wave changes around the UK and in the North Sea have been analysed. This paper integrates the results of this project. Many aspects of the contribution of the North Atlantic Oscillation (NAO) to sea level and wave height have been resolved. The NAO is a major forcing parameter for sea-level variability. Strong positive response to increasing NAO was observed in the shallow parts of the North Sea, while slightly negative response was found in the southwest part of the UK. The cause of the strong positive response is mainly the increased westerly winds. The NAO increase during the last decades has affected both the mean sea level and the extreme sea levels in the North Sea. The derived spatial distribution of the NAO-related variability of sea level allows the development of scenarios for future sea level and wave height in the region. Because the response of sea level to the NAO is found to be variable in time across all frequency bands, there is some inherent uncertainty in the use of the empirical relationships to develop scenarios of future sea level. Nevertheless, as it remains uncertain whether the multi-decadal NAO variability is related to climate change, the use of the empirical relationships in developing scenarios is justified. The resulting scenarios demonstrate: (i) that the use of regional estimates of sea level increase the projected range of sea-level change by 50% and (ii) that the contribution of the NAO to winter sea-level variability increases the range of uncertainty by a further 10–20 cm. On the assumption that the general circulation models have some skill in simulating the future NAO change, then the NAO contribution to sea-level change around the UK is expected to be very small (<4 cm) by 2080. Wave heights are also sensitive to the NAO changes, especially in the western coasts of the UK. Under the same scenarios for future NAO changes, the projected significant wave-height changes in the northeast Atlantic will exceed 0.4 m. In addition, wave-direction changes of around 20° per unit NAO index have been documented for one location. Such changes raise the possibility of consequential alteration of coastal erosion.

The Leman Field, Blocks 49/26, 49/27, 49/28, 53/1, 53/2, UK North Sea

2003 ◽  
Vol 20 (1) ◽  
pp. 761-770 ◽  
Author(s):  
A. P. Hillier
Keyword(s):  
North Sea ◽  
Gas Field ◽  
Dune Sands ◽  
The North ◽  
The North Sea ◽  
To Come ◽  
The Uk

AbstractDiscovered in 1966 and starting production in 1968, Leman was the second gas field to come into production in the UK sector of the North Sea and is still producing gas today. It is classified as a giant field with an estimated initial gas-in-place of 397 BCM of gas in the aeolian dune sands of the Rotliegend Group. The field extends over five blocks and is being developed by two licence groups with Shell and Amoco (now BP Amoco) being the operators

Cold Induced Abnormal Catches of Sole

1998 ◽  
Vol 78 (1) ◽  
pp. 345-347 ◽  
Author(s):  
J.W. Horwood ◽  
R.S. Millner
Keyword(s):  
North Sea ◽  
Cold Water ◽  
The South ◽  
Total Allowable Catch ◽  
The North ◽  
Solea Solea ◽  
The North Sea ◽  
The Uk ◽  
The Eu ◽  
Made In

Large catches of sole (Solea solea) were made in early 1996 from the south-western North Sea. Sole suffer physiological damage in waters below 3–4 C. In February 1996 cold water of 3–4 C unusually extended from the Continental coast onto the Dogger Bank. It is likely that the increased catches were due to the consequential distribution and behaviour of the sole, making them more susceptible to capture.Exceptionally large catches of mature sole (Solea solea (L.)) were made in February 1996 by Lowestoft fishermen from the south-western North Sea. Surprisingly this was not welcome. The UK allocation of the North Sea sole is -4 % of the EU Total Allowable Catch (TAC), and fishermen are restricted nationally, and by the fishing companies, to a tightly managed ration. The Lowestoft Journal (8 March 1996) reported the suspension of a local fishing skipper for not throwing back 5000 kg of sole caught in the Silver Pits. We will show that the abnormal catches were due to exceptionally cold waters.Sole in the North Sea are at the northern extremity of their range, with sole seldom living in waters below 5°C (Horwood, 1993). In fact, North Sea sole were successfully introduced into Lake Quarun, Egypt, where they lived in temperatures in excess of 30°C (El-Zarka, 1965). Young sole migrate from their shallow inshore nursery grounds, such as the Waddensea, as winter approaches (Creutzberg & Fonds, 1971).

The Cormorant Field, Blocks 211/21a, 211/26a, UK North Sea

1991 ◽  
Vol 14 (1) ◽  
pp. 73-82 ◽  
Author(s):  
D. J. Taylor ◽  
J. P. A. Dietvorst
Keyword(s):  
North Sea ◽  
Shetland Islands ◽  
The North ◽  
Stock Tank ◽  
Delta System ◽  
The North Sea ◽  
Reservoir Porosity ◽  
The Uk ◽  
Exploration Well ◽  
Water Depths

AbstractThe Cormorant Oilfield is located approximately 150 km northeast of the Shetland Islands in Blocks 211/2la and 211/ 26a of the UK sector of the North Sea, in water depths of 500-550 ft. The field was discovered in 1972 by exploration well 211/ 26-1 and consists of four discrete accumulations spread along a major, north-south trending fault terrace. Hydrocarbons are produced from Middle Jurassic (Bajocian) sands of the Brent Group, which was deposited in a wave-dominated delta system. The reservoir has a typical gross thickness of 250-300 ft, locally increasing to 550 ft over faults active during sedimentation. Reservoir porosity varies from 16-28%, with average permeabilities ranging from tens of md to 1300md. The accumulation contains under-saturated 34-36° API oil which was initially overpressured by some 1000-1270 psi. The stock tank oil initially in place and ultimate recovery are estimated at 1568 MMBBL and 623 MMBBL, respectively, reflecting a recovery factor of 39%. The reserves are produced through crestally-located wells supported by down-dip water injectors, and exported via two fixed platforms and an underwater manifold centre. To date, 59 wells have been drilled and 324 MMBBL (52%) of the estimated reserves have been produced.

Storm Xaver over Europe in December 2013 and its energy meteorological impacts

2020 ◽  
Author(s):  
Anthony Kettle
Keyword(s):  
Storm Surge ◽  
North Sea ◽  
Tide Gauge ◽  
Offshore Wind ◽  
Northern Europe ◽  
Energy Infrastructure ◽  
The North ◽  
Short Period ◽  
The North Sea ◽  
The Uk

&lt;p&gt;Storm Xaver impacted the northern Europe on 5-6 December 2013. &amp;#160;It developed southeast of Greenland and passed north of Scotland and across southern Norway on a trajectory that led to a cold air outbreak across the North Sea and intense convection activity in northern Europe.&amp;#160; Strong sustained north winds led to a high storm surge that impacted all countries bordering the North Sea. &amp;#160;Storm Xaver was a century scale event with certain locations around the North Sea reporting their highest ever water levels since the start of modern records.&amp;#160; Media reports from the time of the storm chronicle the scale of the disruptions, including many cancelled flights, interrupted rail networks, closed bridges and roads, coastal building collapses, and power blackouts across northern Europe. &amp;#160;Much of this was due to the strong winds, but coastal storm surge flooding was important in the UK, and it led to interrupted port operations around the North Sea.&lt;/p&gt;&lt;p&gt;The storm was important for energy infrastructure and particularly for wind energy infrastructure.&amp;#160; In the northern North Sea, petroleum platforms were evacuated and operations closed ahead of the storm as a precautionary measure.&amp;#160; A number of onshore wind turbines were badly damaged by high winds and lightning strikes in the UK and Germany.&amp;#160; Over the North Sea, wind speeds exceeded the turbine shutdown threshold of 25 m/s for an extended period of time, with economic impacts from the loss of power generation.&amp;#160;&amp;#160; In the German Bight, the FINO1 offshore wind energy research platform was damaged at the 15 m level by large waves. &amp;#160;This was the third report of storm damage to this platform after Storm Britta in 2006 and Storm Tilo in 2007. &amp;#160;Researchers have highlighted the need to reassess&amp;#160; the design criteria for offshore wind turbines based on these kinds of extreme meteorological events. &amp;#160;For the offshore wind industry, an important element of energy meteorology is to characterize both the evolving wind and wave fields during severe storms as both elements contribute to turbine loads and potential damage.&lt;/p&gt;&lt;p&gt;The present conference contribution presents a literature review of the major events during Storm Xaver and impacts on energy infrastructure.&amp;#160; Tide gauge records are reanalyzed to trace the progress of the storm surge wave around the North Sea.&amp;#160; A spectral analysis is used to separate the long period storm surge component, diurnal/semidiurnal tide, and short period components in the original water level record. &amp;#160;The short period component of the tide gauge record is important as it may be linked with infragravity waves that have been implicated in certain cases of offshore infrastructure damage in addition to coastal erosion. &amp;#160;Discussion is made of offshore wave records during the storm.&amp;#160; Storm Xaver is compared with two damaging offshore storms in 2006 and 2007.&lt;/p&gt;

Removal of Topside Units in a Single Lift: The Repsol Yme Field Case Study

2018 ◽  
Author(s):  
Beatriz Alonso Castro ◽  
Terje Birkenes ◽  
Huib Oosterveld
Keyword(s):  
North Sea ◽  
Ballast Water ◽  
Structural Integrity ◽  
Dry Weight ◽  
The North ◽  
Offshore Installations ◽  
Safety And Health ◽  
The North Sea ◽  
The Uk ◽  
Water Tanks

Decommissioning is an emerging sector in the UK and Norway, accounting for 2% of total industry expenditure in 2010 increasing to 8% in 2017. In accordance with existing regulations in the North Sea (OSPAR), dumping, and leaving wholly or partly in place disused offshore installations within the maritime area is prohibited. Over the next eight years, 200 platforms are expected to be removed in the North Sea. There are a number of methods to remove offshore installations: Piece small, Reverse installation and Single lift. In the Single lift approach the jacket or the topside is removed in one piece, minimizing significantly the time offshore and therefore the safety and health incidents. But the Piece Small and Reverse Installation are the most common methods and are established and secure although are time consuming and labor intensive [1]. Several potential candidates for single lift technology at varying levels of technical readiness were considered in the past. The majority of the concepts remained on the drawing board, while some were awaiting project commitment. The only that was matured further than this is the Pioneering Spirit. Yme, its first commercial lift, gave this concept the “proven” status. The Yme MOPU, owned by Repsol, was a jack-up type platform standing on three steel legs of 3.5 m diameter. The dry weight of the MOPU was approximately 13,500 t. The Yme MOPU was a challenging unit to remove mainly for three reasons: The platform motions due to the lack of stiffness in the leg support, its position in contact with the caisson wellhead platform, and the fact that the legs could not be pre-cut before the operation. The method selected to remove the platform was Single lift, using the dynamically positioned platform installation and removal vessel Pioneering Spirit. The lifting arrangement consisted of 12 lift beams combined and connected in pairs to yokes. Five specifically designed yokes were installed. The yokes connect the TLS with the MOPU. The structural integrity of each interface was assessed with FE analysis. The Ballast system was used to provide additional clearance. Pioneering Spirit has a total of eighty-seven ballast water tanks, including four so called ‘Quick Drop Ballast Water Tanks’. The removal of the MOPU was performed successfully the 22nd August 2016, after two days work offshore.

The Flora Field, Blocks 31/26a, 31/26c, UK North Sea

2003 ◽  
Vol 20 (1) ◽  
pp. 549-555 ◽  
Author(s):  
R. D. Hayward ◽  
C. A. L. Martin ◽  
D. Harrison ◽  
G. Van Dort ◽  
S. Guthrie ◽  
...  
Keyword(s):  
North Sea ◽  
Upper Jurassic ◽  
Water Contact ◽  
Upper Carboniferous ◽  
The North ◽  
Recoverable Reserves ◽  
The North Sea ◽  
Oil Water ◽  
The Uk ◽  
Clay Formation

AbstractThe Flora Field straddles Blocks 31/26a and 31/26c of the UK sector of the North Sea on the southern margin of the Central Graben. The field is located on the Grensen Nose, a long-lived structural high, and was discovered by the Amerada Hess operated well 31/26a-12 in mid-1997.The Flora Field accumulation is reservoired within the Flora Sandstone, an Upper Carboniferous fluvial deposit, and a thin Upper Jurassic veneer, trapped within a tilted fault block. Oil is sourced principally from the Kimmeridge Clay Formation of the Central Graben and is sealed by overlying Lower Cretaceous marls and Upper Cretaceous Chalk Group.Reservoir quality is generally good with average net/gross of 85% and porosity of 21%, although permeability (Kh) exhibits a great deal of heterogeneity with a range of 0.1 to <10000mD (average 300 mD). The reservoir suffers both sub-horizontal (floodplain shales) and vertical (faults) compartmentalization, as well as fracturing and a tar mat at the oil-water contact modifying flow and sweep of the reservoir. Expected recoverable reserves currently stand at 13 MMBBL

The Magnus Field, Block 211/7a, 12a, UK North Sea

1991 ◽  
Vol 14 (1) ◽  
pp. 153-157 ◽  
Author(s):  
M. Shepherd
Keyword(s):  
North Sea ◽  
Upper Jurassic ◽  
Hydrocarbon Source Rock ◽  
Submarine Fan ◽  
Oil Accumulation ◽  
The North ◽  
Fault Block ◽  
The North Sea ◽  
The Uk ◽  
Clay Formation

abstractMagnus is the most northerly producing field in the UK sector of the North Sea. The oil accumulation occurs within sandstones of an Upper Jurassic submarine fan sequence. The combination trap style consists of reservoir truncation by unconformity at the crest of the easterly dipping fault block structure and a stratigraphic pinchout element at the northern and southern limits of the sand rich fan. The reservoir is enveloped by the likely hydrocarbon source rock, the organic rich mudstones of the Kimmeridge Clay Formation.

Stratigraphy of the oil and gas reservoirs: UK Continental Shelf

1991 ◽  
Vol 14 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Stewart Brown
Keyword(s):  
Continental Shelf ◽  
North Sea ◽  
Oil And Gas ◽  
Sedimentary Basins ◽  
Public Domain ◽  
The Public ◽  
The North ◽  
Marine Gravity ◽  
The North Sea ◽  
The Uk

The petroliferous sedimentary basins of the UK Continental Shelf are remarkable for the diversity of their reservoir strata. Reservoir rocks in fields currently in production range in age from Devonian to earliest Eocene, but significant hydrocarbon discoveries have also been made in rocks as as young as the mid-Eocene. The reservoirs are predominantly siliciclastic rocks, with facies ranging from continental fluvial and aeolian, to marine gravity flow deposits from sub-wave base environments.In this paper stratigraphic context of the producing horizons in the UK Continental Shelf (UKCS), principally the North Sea, is reviewed, and the sedimentation of the reservoir strata placed in an outline geological history. The main producing horizons are described in summary. Matters of stratigraphic terminology and correlation both between fields and between basins are discussed.A lithostratigraphy for the UK southern North Sea was established by Rhys (1974), and for the central and northern North Sea by Deegan & Scull (1977). Although these schemes have proved to be fairly robust, in the last 13 years the acquisition of new data plus a proliferation of new terms not fully documented in the public domain, argue strongly for a comprehensive revision and rationalization which is beyond the scope of this paper. Attempts in the public domain to standardize nomenclature across international boundaries in the North Sea, pursued by Deegan & Scull (1977) for the UK and Norwegian sectors, have lapsed for the most part in subsequent years.Economic basement in the UK North Sea can be regarded at present

Sign in / Sign up

Export Citation Format

Share Document