As part of the the CHIMNEY project (NERC grant NE/N016130/1), multibeam bathymetry data were collected during RRS James Cook cruise JC152 to a subsea chimney structure in the northern North Sea around Scanner Pockmark in August-September 2017. Multibeam data were acquired using a Kongsberg EM-710 multibeam echosounder and processed by the JC152 Science Party. In conjunction with seismic profile data acquired on the same cruise, these data will help scientists understand the surface and internal structure and origin of the chimney structure. This will facilitate estimation of the permeability of the chimney and its surroundings, and enable leakage pathways to be determined. The potential for past oil and gas reservoirs and saline aquifers to be used as Carbon Capture and Storage (CCS) reservoirs of atmospheric CO2 can subsequently be explored. The safety of storing CO2 in such reservoirs is dependent on fully exploring the risks of any leakage via such chimney structures, which the CHIMNEY project will investigate. CHIMNEY is funded by the Natural Environment Research Council (NERC), and involves scientists from the National Oceanography Centre, Southampton and the University of Edinburgh. Investigators will work closely with project partners GEOMAR, Lawrence Berkley National Laboratory, CGG and Applied Acoustics. The project is complementary to the EU-funded Horizon 2020 project: Strategies for Environmental Monitoring of Marine Carbon Capture and Storage (STEMM-CCS).

The GEBCO_2021 Grid is a global continuous terrain model for ocean and land with a spatial resolution of 15 arc seconds. In regions outside of the Arctic Ocean area, the grid uses as a base, Version 2.2 of the SRTM15+ data set between latitudes of 50 degrees South and 60 degrees North. This data set is a fusion of land topography with measured and estimated seafloor topography. This version of SRTM15+ is similar to version 2.1 [Tozer et al., 2020] with minor updates. Version 2.2 uses predicted depths based on the V29 gravity model [Sandwell et al., 2019] and approximately 400 small areas containing suspect data were visually identified and removed from the grid. Included on top of this base grid are gridded bathymetric data sets developed by the four Regional Centers of The Nippon Foundation-GEBCO Seabed 2030 Project. The GEBCO_2021 Grid represents all data within the 2021 compilation. The compilation of the GEBCO_2021 Grid was carried out at the Seabed 2030 Global Center, hosted at the National Oceanography Centre, UK, with the aim of producing a seamless global terrain model. Outside of Polar regions, the gridded bathymetric data sets are supplied by the Regional Centers as sparse grids, i.e. only grid cells that contain data were populated, were included on to the base grid without any blending. The data sets supplied in the form of complete grids (primarily areas north of 60N and south of 50S) were included using feather blending techniques from GlobalMapper software. The primary GEBCO_2021 grid contains land and ice surface elevation information - as provided for previous GEBCO grid releases. In addition, for the 2021 release a version with under-ice topography/bathymetry information for Greenland and Antarctica is also available. The GEBCO_2021 Grid has been developed through the Nippon Foundation-GEBCO Seabed 2030 Project. This is a collaborative project between the Nippon Foundation of Japan and the General Bathymetric Chart of the Oceans (GEBCO). It aims to bring together all available bathymetric data to produce the definitive map of the world ocean floor by 2030 and make it available to all. Funded by the Nippon Foundation, the four Seabed 2030 Regional Centers include the Southern Ocean - hosted at the Alfred Wegener Institute, Germany; South and West Pacific Ocean - hosted at the National Institute of Water and Atmospheric Research, New Zealand; Atlantic and Indian Oceans - hosted at the Lamont Doherty Earth Observatory, Columbia University, USA; Arctic and North Pacific Oceans - hosted at Stockholm University, Sweden and the Center for Coastal and Ocean Mapping at the University of New Hampshire, USA.

This geophysical survey has been carried out by Marine Geophysics Unit of British Geological Survey (BGS) for BGS, the survey took place from June to July 1971 in the North Scotland and Minch area, on board the MV Surveyor. The purpose was to collect data as part of a regional mapping programme. Sea floor data were collected using Echosounder and Transit sonar. These data are archived by BGS. No BGS survey report currently available, IGS 1971 annual report contains summary.

This British Geological Survey (BGS) marine geophysical survey took place in December 1969 in the Firth of Clyde on board the MV Stella Maris. The purpose was to investigate the superficial deposits of the clyde area, this survey was Phase 4 of a 5 phase project. Sea floor data were collected using echosounder. Sub-bottom seismic profiling data were collected using Pinger and Sparker. These records are archived by BGS. Details of the survey are contained in IGS report 73/9.

This British Geological Survey (BGS) marine geophysical survey took place in March 2009 in the Medway & Swale Estuaries on board the Medway Surveyor. The purpose was to obtain the data necessary for the Coastal Evolution of the Medway & Swale estuary targeting the Holocene thickness and distribution of sediments within the Paleo Valley. Sea floor data were collected using a ODOM Echotrac III run by Peel Ports. Sub bottom seismic profiling data were gathered by BGS using a surface tow boomer. Most of the data were recorded digitally, but paper records were generated also. These data are archived by BGS. Technical details of the survey are contained in BGS Internal Report OR/09/014.

The GEBCO_2019 Grid is a global continuous terrain model for ocean and land with a spatial resolution of 15 arc seconds. The grid uses as a ‘base’ Version 1 of the SRTM15_plus data set (Sandwell et al). This data set is a fusion of land topography with measured and estimated seafloor topography. It is largely based on version 11 of SRTM30_plus (5). Included on top of this base grid are gridded bathymetric data sets developed by the four Regional Centers of The Nippon Foundation-GEBCO Seabed 2030 Project, and from a number of international and national data repositories and regional mapping initiatives. The GEBCO_2019 Grid represents all data within the 2019 compilation. The compilation of the GEBCO_2019 Grid was carried out at the Seabed 2030 Global Center, hosted at the National Oceanography Centre, UK, with the aim of producing a seamless global terrain model. The majority of the compilation was done using the 'remove-restore' procedure (Smith and Sandwell, 1997; Becker, Sandwell and Smith, 2009 and Hell and Jakobsson, 2011). This is a two stage process of computing the difference between the new data and the ‘base’ grid and then gridding the difference and adding the difference back to the existing ‘base’ grid. The aim is to achieve a smooth transition between the 'new' and 'base' data sets with the minimum of perturbation of the existing base data set. The data sets supplied in the form of complete grids (primarily areas north of 60N and south of 50S) were included using feather blending techniques from GlobalMapper software. The GEBCO_2019 Grid has been developed through the Nippon Foundation-GEBCO Seabed 2030 Project. This is a collaborative project between the Nippon Foundation of Japan and the General Bathymetric Chart of the Oceans (GEBCO). It aims to bring together all available bathymetric data to produce the definitive map of the world ocean floor by 2030 and make it available to all. Funded by the Nippon Foundation, the four Seabed 2030 Regional Centers include the Southern Ocean - hosted at the Alfred Wegener Institute, Germany; South and West Pacific Ocean - hosted at the National Institute of Water and Atmospheric Research, New Zealand; Atlantic and Indian Oceans - hosted at the Lamont Doherty Earth Observatory, Columbia University, USA; Arctic and North Pacific Oceans - hosted at Stockholm University, Sweden and the Center for Coastal and Ocean Mapping at the University of New Hampshire, USA).

This marine geophysical survey took place in March 2009 in Loch Fitty in Fife aboard the small outboard powered 'Tuppence' provided by ACS Coring Services. This survey was carried out by the British Geological Survey (BGS) as part of a study commissioned by Scottish Coal to ascertain the depth of sediment covering the coal seams beneath Loch Fitty. BGS personnel were also involved in the operation. Subsurface seismic data were gathered using a Surface Tow Boomer. Most of the data were recorded digitally, but paper records were generated also. These data are archived by BGS. Technical details of the survey are contained in BGS Internal Report CR/09/014.

This marine geophysical survey took place from 05/07/92 – 06/07/92 in the area of the Barra Fan on board the RV Kommandor Michael. The survey was carried out by the British Geological Survey (BGS), Marine Biological Association and Dunstaffnage Marine Laboratory. The aim of the survey was to investigate the source and fate of methane in marine sediments. Sub bottom seismic profiling data were collected using a Deep Tow Boomer. These data are archived by BGS. Technical details are contained in BGS Report WB/92/27. Report: Dobinson, A. 1992. Barra Fan Project: Geophysical Operations Report - Project 92/02, https://nora.nerc.ac.uk/id/eprint/529922/. GeoIndex Offshore - https://mapapps2.bgs.ac.uk/geoindex_offshore/home.html?cruise=1992/2&.

This high resolution marine multi-channel seismic survey commissioned by the Institute of Geological Sciences on behalf of Department of Energy took place in the Northern North Sea during 1st-27th November 1979 (Phase 1) aboard MV Aqua Star and 1st-14th February 1980 (Phase2) aboard Gardline Tracker. Phase 1 (Lines 1-5) was carried out by Fairfield Auatronics Ltd and Phase 2 (lines 5B-9) by Gardline surveys Ltd. Line coverage total 445km (Phase1 - 180km; Phase 2 - 265km). Sea floor data were collected using Echo sounder. Subsurface seismic data were gathered using a 9/15KJ sparker and line 4, Fairflex sleeve exploder. Survey details are contained in Fairfield and gardline acquisition reports and BGS technical report WB/MG/81/124.

This marine geophysical survey took place in August 2000 on board the RV Hakon Mosby on the AFEN slide, Shetlands margin area. This was a joint contribution of the University of Bergen and the British Geological Survey to the EU COSTA (Continental Slope Stability) project. The main objective of the COSTA project is the assessment of continental slope stability along the European Continental Margin with respect to natural processes and human activity. Subsurface seismic data was collected using BGS Deep-tow boomer and Halliburton sleeve gun system. Technical details of the survey are contained in University of Bergen report 100-02/00 (BGS2000/074).