Academic Research Projects using INSS data

Xavier Monteys: GSI
Mapping West of the Porcupine Bank

Recent depositional environments and processes are being investigated on the upper continental slope of the western margin of the Porcupine Bank. A multidisciplinary study using high-resolution deep-towed sidescan sonar, multibeam sonar, shallow seismic, underwater TV-system and bottom sampling was conducted on this area which is dominated by a recently discovered large cluster of giant carbonate mounds limited eastwards by a N/S fault scarp system and to the west by the steep edge of the deep water canyon, Porcupine Bank canyon.

Amongst the main goals is the study in detail of the morphology, structure and composition of seabed features such as carbonate mounds, scarps, faults, iceberg ploughmarks and other glacial features. Particular attention is being paid to the biology of the mounds, deep water corals and microfauna, and to their relationship with the underlying basement. Several outcrops were identified both in mounds and on the actual fault scarp and sampled for further laboratory studies. All of this research will contribute to a better understanding of the regional hydrodynamic regime as well as creating a better framework for paleoclimate studies.

Multibeam seabed unsupervised classification, based on backscatter image segmentation, has been performed to the entire region.

Lena Øverbø: UCD
Spatial and temporal variations in bottom currents and other slope processes operating on the marginal slopes of the Rockall Trough, offshore West Ireland

Shallow coring of the marginal slopes of the Rockall Trough was undertaken by M.V. Challenger and M.V. Polarboy during summers 1998 and 1999 under the auspices of the Rockall Studies Group of the Irish Petroleum Infrastructure Programme. This project studies a subset of 60 of these gravity cores integrating them with other seabed data such as shallow seismic, TOBI sidescan imagery and high-resolution GSI bathymetry data. The cores ranges in length from 0.35 to 3.14 m and were acquired on four sites along the margins of the trough: (i) West Porcupine Bank Slopes; (ii) North Porcupine Bank Slopes; (iii) East Rockall Trough and (iv) West Rockall Trough. Key aims of the study are to characterise the magnitude and frequency of gravity-driven, downslope sediment transfer and to assess the importance of bottom current reworking and winnowing on the slope. In particular the project will study how the bottom currents vary with time and space within the Rockall Trough. The study also aims to provide new insights into the evolution of the NE Atlantic slopes under glacial/interglacial forcing.

Archie Donovan: GSI
The GIS integration of off-shore and on-shore data utilising the specific case study area of Dublin Bay

There are various integration issues involved with the unification of off-shore to on-shore datasets, these include, but are not limited to, datums (both horizontal and vertical), projections, the temporal nature of data, accuracy, scale and generalisation.
Mariners desire is for seamless geo-spatial digital data which can provide the backdrop to their needs; be this navigation, warfare, fishing, mineral exploration, leisure or a multitude of other activities. Geographers and GIS users wish to use the data seamlessly for their modelling needs; such as modelling of slope stability, flood plane, river estuarine process, tide, seabed bottom type classification, habitat mapping and coastal erosion and vulnerability and other activities.

The creation of seamless data is, understandably, far more than just joining more than one digital dataset together. Issues such as horizontal datum, projection, temporal changes, error budgets (including accuracy, scale and generalisation) and vertical datums must be considered. Vertical datums are particularly relevant to mariners, particularly in the near-shore area. Ignoring these technical concerns will cause datasets of geo-spatial information to end up as potentially meaningless and unreliable information. It is proposed to research, evaluate, comment and hopefully to suggest solutions where possible and areas for further research.

Niall Mc Cormack: DIT Bolton St.
An investigation into the accuracy of the Polpred and Fugro HP MSS methods of tidal prediction

The aim of the thesis is to examine the accuracies of two tidal prediction computer programs, Polpred and Fugro HP MSS. These two prediction programs are being compared against both coastal and offshore tide gauge data.

The correct tide model is essential to the accurate surveying of the bathymetry of the seabed. The comparison is being made in the Irish Conservation Box, Southern Section. This area is located off the coast of Tralee, Co. Kerry. This area contains very few coastal or offshore tide gauges, and relies heavily on the accuracy of tidal prediction models. A coastal tide gauge was installed at Allihies on the 7th of September 2004. This coastal tide gauge is being used as a cross check on the accuracy of the prediction programs, in an effort to detect gross errors. In addition to this offshore tide gauges have been deployed in the survey area, and left to collect data for a period of approximately 5 days. There is one offshore tide gauge onboard the R.V. Celtic Explorer, which has been deployed on 4 separate occasions. The thesis will examine the relationship between the coastal tide gauge at Allihies, the offshore tide gauge data, Fugro HP MSS and Polpred prediction program. A complication in using the offshore tide gauge data is that it is not referenced to the Irish vertical datum at Malin Head, Co. Donegal. The Polpred Mean Sea Level must therefore be used for the offshore tide gauge. If possible, the accuracy of this Polpred Mean Sea Level will be determined

Gavin Elliot: UCD
The development of Cenozoic basin margins, slopes and slope failures in the Porcupine and Rockall troughs, offshore Ireland

INSS data is being used as part of a PhD project in the Department of Geology at UCD that commenced in October 2002. The PhD project, entitled " The development of Cenozoic basin margins, slopes and slope failures in the Porcupine and Rockall troughs, offshore Ireland" is being carried out under the supervision of Prof P.M. Shannon and Dr P.D.W. Haughton. INSS data is being integrated with existing datasets (2D seismic reflection data, TOBI sidescan sonar & 3.5 kHz echosounder) to look at the evolution of the basin margins through the Cenozoic, with an emphasis on looking at the styles of failure in both time and space along the margins. Particular interest is focused on utilising the INSS data to examine the canyon systems on the eastern margin of the Rockall Trough and the large-scale failure features on the western side of the trough. See departmental website for further details of the project: http://www.ucd.ie/geology/home.html
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