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Research Themes

This section provides examples and descriptions of the range of SERPENT activities and research aims carried out during offshore visits in this region.

Biodiversity & Habitat Mapping

The assessment of physical impacts on the sediment environment and the associated organisms around the well head can be made visually by carrying out ROV operated video inspections. This involves conducting radiating transects around the well head, and using these data to produce sediment impact maps that help to outline the horizontal extent of the disturbance. The transect data are also used to examine the impact on the megafaunal community around the survey area.

Sedimentation

The visual approach of mapping the drill spoil distribution is complemented by the deployment of graduated poles (marker buoys) around the well head. The accumulated sediment along the marker buoys adds a vertical component to the impact assessment.

Changes in particle size & chemical analysis

Sediment push cores can be utilised to obtain virtually undisturbed sediment samples from pinpointed locations around the drilling area. These samples are analysed for a suite of chemical parameters as well as particle size distributions and as such can be used in groundtruthing the sediment impact maps based on visual inspections.

Macrofauna sediment sampling

Sediment samples for macrofaunal analysis can be collected by using a modified Ekman Grab. The Ekman Grab is essentially a box shaped (15x15x15 cm) sampling device that has spring loaded doors that close and seal the sample when the device is triggered. Due to its larger size (surface area) this sampler is more suitable for collecting macrofaunal samples.

Animal Stress

Building on the impact on biodiversity patterns through drilling, our work on Animal stress examines shock proteins that are sequestered by an animal when it is placed under a level of stress. We aim to look at how the species present in UK waters respond to habitat disturbance and to examine the level of stress and recovery in these species. The collection of high quality samples and habitat mapping with an ROV is integral to this work.

Ecological Highlights and specimen capture

The scientific purpose of collecting extended close-up video footage and digital stills images is to aid in the identification of the organisms as well as to highlight interesting patterns in their behaviour. Visual footage provides a record of the appearance of animals in life as this can often differ significantly from its appearance as observed from the specimens collected by more traditional benthic trawling methods.

Species level identification requires the collection of actual specimens in virtually all cases. Capturing examples of the dominant fauna can enhance the quality and value of the video surveys. Specimen capture can be done very precisely using a suction sampler, such as a zip pump. Samples of scavenging macrofauna can also be collected in baited traps.

In situ experiments

Benthic incubation chambers
These chambers can measure the oxygen consumption rates of benthic organisms and may be used to investigate ecotoxicology related to increased levels of drilling fluids, discharge muds and production water. This system can also be used to look at burial stress impacts on the sponge and coral species found in the area.

Amphipod traps/Baited treatments
Amphipods are extremely common in the deep sea and are important scavengers, aiding in the decomposition of dead marine animals. Free swimming scavenging species are notoriously difficult to capture, however the SERPENT scavenger traps have proved very successful on a number of missions. Mackerel or other oily fish is used as bait to attract the amphipods, which enter the chamber through a one-way valve trapping them in the collection tube. The traps are planted into the sediment, but remain free to rotate and align with the current to optimise their trapping efficiency.

Bioturbation
Bioturbation can be defined as sediment reworking of particles by organisms inhabiting the seabed environment. As such it has direct influences on the depth of the oxygenated sediment layer and the rate of recycling chemical compounds. This experiment aims to investigate the bioturbation rates across a gradient of impacted and non-impacted sediments.

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Research Locations

Buzzard Field

The Buzzard field is located in the Outer Moray Firth, central North Sea, 100km northeast of Aberdeen. The field straddles two licences - P.986 (Blocks 19/10 and 20/6) and P.928(S) (Blocks 19/5a and 20/1S) - and the water depth in the area is about 100m.

The field will be developed by three bridge-linked platforms supporting the wellhead facilities (W), production facilities (P) and a third platform supporting living quarters and utilities (UQ).

Foinaven Field

The Foinaven field is located 190km west of the Shetland Islands in UK blocks 204/19 and 204/24a and takes its name from the prominent mountain of North West Sutherland. The average water depth at field location is circa 450m (1470ft) - beyond the limits of most fixed jacket installations commonly used in the more shallow waters of the North Sea. The key distinctive physical characteristics of the marine environment in the Foinaven area are the water depth (450m), strong subsea currents (4.5 km/hr) and low seabed temperatures (-1.5C).

Schiehallion Field

The Schiehallion field was discovered in 1993, some 15 kilometres to the east of the earlier Foinaven Field. The field lies predominantly in blocks 204/20 and 204/25, 175 km west of Shetland in a water depth of between 350 to 450 metres.

Laggan Field

The Laggan field is situated on the southern bank of the Faroe-Shetland Channel. The location is in approximately 600m of water on the east slope of the Faroe-Shetland Channel, 80km from the Shetland Islands and 60km from the UK-Faroes median line.

It is a very interesting area where the warm Atlantic surface waters meet Arctic temperature (0 to -2 degrees C) deep waters from the Norwegian Sea.

Rosebank & Lochnagar Field

The Rosebank and Lochnagar work site lies in an area of permanent cold-water within the Faroe-Shetland Area of the North East Atlantic, approximately 126km from the closest coast (Esha Ness on Shetland), in water depths approaching 1200m.. The Faroe-Shetland Channel is an important area for exchange of water between the Arctic and Atlantic oceans with north west flowing Atlantic water (>8°C) overlaying cold, subzero temperature, Norwegian Sea Deep Water (approx. 2 to -1°C) flowing to the south west.