This dataset comprises the geochemical and mineralogical analysis of six samples of massive sulphide deposit. Three samples were obtained from seafloor massive sulphide (SMS) systems obtained during RV Celtic Explorer cruise CE11009 (Mid-Atlantic Ridge 45° N, 2011) and RRS James Cook cruises JC082 (Mid-Cayman Spreading Centre, 2013) and JC138 (Mid-Atlantic Ridge at 26° N, 2016). Three samples were obtained from land-based volcanogenic massive sulphide (VMS) deposits on Wetar Island, Indonesia. It is thought these samples were obtained in 2002 at Kali Kuning and Lerokis Zones 4 and 5, but users should be aware there is little to no metadata about the Wetar Island sample origins. The sample analyses includes: (1) bulk geochemical analysis of sulphide samples by inductively coupled plasma mass spectrometry (ICP-MS) for bulk and effluent analysis and inductively coupled plasma orbital emission spectrometry (ICP-OES), (2) petrographic descriptions of samples by reflective microscopy, (3) geochemical analysis of seawater samples during experiments by ICP-MS, (4) mineralogical analyses (X-ray Diffraction) of sulphide samples, (5) mineralogical analyses by Scanning Electron Microscope and energy dispersive X-ray spectroscopy (SEM-EDS) on sulphide grains, (6) SEM backscattered electron (BSE) images of reacted sulphide grains, and (7) surface areas determined by Brunauuer-Emmett-Teller (BET) surface area analysis. All analyses were undertaken as part of a PhD project which aimed to enhance understanding of sulphide oxidation kinetics, the formation of Fe-oxyhydroxide from sulphide oxidation, its capacity to retain metals that would otherwise be lost to seawater in SMS systems, and the implications for potential seafloor mining operations. Analyses took place at the University of Southampton and the National Oceanography Centre Southampton, funded under the Natural Environment Research Council (NERC) project Ultramafic-hosted mineral Resource Assessment (ULTRA) grant, NE/S004068/1. This collection consists only of the data collected under the PhD project and not all data associated with the ULTRA project.

This dataset consists of measurements of 224Ra and macronutrients in core top water, porewaters and sediments, as well as calculated 224Ra and macronutrient fluxes (via 224Ra/228Th disequilibrium) from benthic incubations of replicate mesocosms containing selected benthic macrofauna. The experiments were conducted at the Biodiversity Ecosystem Futures Facility (BEFF lab) at the National Oceanography Centre Southampton during 2022. Sediment was collected from Rame Mud, Plymouth, and benthic organisms were collected from Rame Mud and from Loch Linhe, Scotland. For each incubation, homogenised, sieved (500 µm) sediment was added to a mesocosm to 10 cm depth, overlain by approximately 15 cm (approx. 1.3 L) seawater (0.45 µm filtered, UV sterilised, salinity 33), and left to settle for 24 hours before conducting a full water exchange. After water exchange, 1 individual of either Paraleptopentacta elongata , Edwardsia claparedii, Turritellinella tricarinata, or Amphiura chiajei was weighed and morphological measurements were taken before being added to the mesocosm. 3 replicates containing 1 individual were run for each species, in addition to 3 replicate control mesocosms containing no macrofauna. All mesocosms were continually aerated and maintained in a temperature-controlled water bath for 10 days under a 12:12h on/off light cycle. On days 4 and 8, 2.5ml of a mixed Phaeodactylum tricornutum: Tetraselmis suecica phytoplankton culture was added to all mesocosms. For a subset of mesocosms (mesocosms 14 and 15 ), daily water column nutrient samples (10 ml, 0.2 µm filtered) were taken ~5 cm below the water surface and frozen at -20°C for subsequent analysis. Experiments 1 & 2 were set up in the same manner, except that in experiment 2 only one species was included, but at higher replication (8 replicate mesocosms containing 1 individual each of E. claparedii + 1 control mesocosm). Water samples for macronutrient concentrations were analysed using a QuAAtro 39 autoanalyser (Seal Analytical) and samples for Ra activity were analysed using a Radium Delayed Coincidence Counter (RaDeCC) system.The work was conducted to quantify the influence of different species and individuals of benthic macrofauna on benthic flux, using 224Ra as a naturally occurring tracer of sediment-seawater exchange. For further information, please see the associated research paper doi: 10.1002/lno.70033

This dataset comprises physical, chemical and biological oceanographic measurements collected from the Mid-Atlantic Ridge as part of the UK 'RidgeMix' project between 2015 and 2016. Physical measurements include water column profiles of temperature, conductivity, current speed/direction and turbulence. These are supplemented by i) chemical samples targeting inorganic nutrients, oxygen and isotopes of radium/nitrate, ii) biological samples to understand plankton distribution and to determine chlorophyll and enzyme concentrations. Samples were collected from the water column above the Mid-Atlantic Ridge, between latitudes of approximately 23 and 39 degrees North. Sampling commenced in September 2015 with the deployment of moored sensors (thermistors, MicroCATs and ADCPs). This was followed up with a dedicated research cruise (JR15007) between May and July 2016. During this cruise standard observational measurements were undertaken (including CTD, LADCP, SADCP and discrete water sampling), together with more specialised data collection activities (including deployment of turbulence profilers, standalone pumps, zooplankton nets, ocean gliders and a drifting wirewalker mooring). The cruise was also used to recover the moored instruments deployed the previous year. RidgeMix aims to investigate the mixing from internal tides over ridges and seamounts and the biogeochemical implications of this. The project is funded by a Responsive Mode grant from the UK Natural Environment Research Council (NERC) and ran from 2014 until 2019. RidgeMix was led by Professor Jonathan Sharples from the University of Liverpool, in collaboration with Principal Investigators from the National Oceanography Centre (Dr Matthew Palmer) and University of Southampton (Professor Alberto Naveira Garabato). This dataset collection brings together the observational component of RidgeMix. Users are advised to contact Principal Investigators for access to associated ocean modelling output from the project. Assembly of the observational dataset is still ongoing with BODC currently holding CTD and discrete sample data (chlorophyll and dissolved inorganic nutrients).

This dataset comprises a variety of sediment core data from the Semenov Hydrothermal Field region of the Mid-Atlantic Ridge, collected during RRS James Cook cruises JC224 (March - April 2022) and JC254 (October - November 2023). A total of 29 gravity cores, 9 mega-cores, and 25 push cores were successfully recovered. Analysis of the sediment core samples was conducted at the British Ocean Sediment Core Research Facility (BOSCORF), where the cores are held for long term storage, and included: imaging, spectrometry, geophysical and geochemical measurements of sediment and porewaters, radiocarbon dating, and stable isotope analysis. The main coring equipment used during both cruises was a gravity corer to collect sediment cores of up to 3 m in length. For JC224, a mega-core, with a USBL transponder attached to the frame, was used to obtain undisturbed cores from the upper 40 cm of the sediment surface. For JC254, push cores were also collected during several Remotely Operated Vehicle (ROV) dives using the Isis vehicle. The key objectives of the sediment coring were: (1) to reconstruct the history of the hydrothermal activity by dating plume fallout layers in the sedimentary record, and (2) to assess the role of the sediment cover in the preservation of seafloor massive sulphide (SMS) deposits in an ultra-slow spreading scenario. The data were collected as part of a PhD project funded under the Natural Environment Research Council (NERC) project Ultramafic-hosted mineral Resource Assessment (ULTRA) grant, NE/S004068/1. This collection consists only of the data collected under the PhD project and not all data associated with the ULTRA project.

This dataset comprises the following water body parameters: pressure; density; salinity; temperature; fluorescence; oxygen; dissolved inorganic nutrients; dissolved inorganic carbon (DIC); particulate carbon (PC); particulate organic carbon (POC); particulate nitrogen (PN); alkalinity; pH; chlorophyll; photosynthetically active radiation (PAR); delta 15 N isotopic composition of PN and nitrate; delta 13 C isotopic composition of POC; delta 18 O isotopic composition of nitrate; ratio of oxygen isotopes. This dataset also includes dissolved inorganic nutrients in sediment pore water, and major and minor element concentrations in sediment. Data were sampled on the West Antarctic Peninsula (WAP), more specifically in Ryder and Marguerite Bays. Measurements were obtained from in situ sensors, samples collected by box coring, or by Niskin bottles mounted on the CTD rosette of RRS James Clark Ross during cruises JR20141231 (JR307, JR308) and JR15003, which took place from 31 December 2014 to 07 January 2015 and from 17 December 2015 to 13 January 2016 respectively. Samples were also collected from Niskin bottles deployed with a hand-cranked winch or 12 V electric bilge pump from a rigid-hulled inflatable boat between 16 November 2013 and 21 March 2016. Sediment samples were analysed for major and minor element composition by X-ray fluorescence spectroscopy at the School of Geosciences, University of Edinburgh. This research project aimed to examine the ways in which ongoing climate change and sea ice decline at the WAP impact upon nutrient budgets and biogeochemical cycling throughout the region, and to trace the movement and modification of circumpolar deep water across the WAP shelf and its influence on macronutrient and inorganic carbon supply to productive coastal regions. Data were generated by Sian Henley (University of Edinburgh), Hugh Venables and Michael Meredith (British Antarctic Survey), Elizabeth Jones (University of Groningen), Katharine Hendry (University of Bristol), and Yvonne Firing (NOC Southampton), with funding from NERC Independent Research Fellowship (NE/K010034/1), the University of Edinburgh School of Geosciences, the British Antarctic Survey Polar Oceans Program, the Netherlands Polar Program (NOW), British Antarctic Survey CGS-109, and NERC NC Funding for SR1b repeat transect (PI Firing). Additional contributors to the dataset were Malcolm Woodward (Plymouth Marine Laboratory), Melanie Leng (British Geological Survey) and Colin Chilcott and Nicholas Odling (University of Edinburgh). All data have been received by BODC to be processed and quality controlled using in-house BODC procedures and made available online.

The Northern Seas Programme dataset comprises hydrographic, biogeochemical, biological and meteorological data. Hydrographic profiles provided measurements of parameters such as temperature, salinity, fluorescence and dissolved oxygen, while current velocities and acoustic backscatter were also measured. A comprehensive water sampling program permitted the collection of biogeochemical data including concentrations of various organic compounds, dissolved gas concentrations and radioactivity. Water samples were also analysed for phytoplankton, zooplankton and viruses. Larger biological samples were obtained from the water column using trawl nets and cetacean distributions were monitored using hydrophone arrays. Sediment samples were collected at various locations and analysed for biogeochemical parameters and zoobenthos. Sample data were supplemented by those derived from experiments, while bathymetry and meteorological parameters were measured across the study area. Data collection was undertaken in the Irish and northern North Seas, across the NE Atlantic and up to the marginal Arctic pack ice zone. This includes the territorial waters of the UK, Norway and the Russian Arctic, and extends from coastal fjords to the ocean margins. The data were collected during the period 2001-2007 over a number of cruises: RRS Discovery cruise D257, RRS James Clark Ross cruises JR75 and JR127, RRS Charles Darwin cruise CD176 and FS Poseidon cruise PO300/2. Measurements were taken using a variety of instrumentation, including conductivity-temperature-depth (CTD) profilers with attached auxiliary sensors, bathymetric echosounders, sediment samplers, trawl nets and acoustic Doppler current profilers (ADCPs), while incubation chambers were used for shipboard experiments. The programme was designed to advance the understanding of how marine systems in Northern Seas respond to environmental and anthropogenic change and was developed in three themes: Theme A - Understanding fjordic systems insights for coastal and oceanic processes; Theme B - Ocean Margins: the interface between the coastal zone and oceanic realm; Theme C - Measuring and modelling change: sea sensors and bioinformatics. Theme B included the Ellett Line Time Series. The Northern Seas Programme was co-ordinated by the Scottish Association for Marine Science (SAMS). Data from the programme are held at the British Oceanographic Data Centre.

The dataset contains hydrographic and biogeochemical data, including continuous underway measurements of surface temperature, salinity, nutrients, chlorophyll and attenuance, irradiance and bathymetric depth. Underway dissolved oxygen and/or trace metal measurements were also collected on occasion. Hydrographic profiles of temperature, salinity, transmittance, fluorescence, dissolved oxygen (data often of poor quality) and scalar irradiance were undertaken, and associated water samples were routinely analysed for suspended particulate material (SPM), chlorophyll, nutrients and particulate organic carbon/particulate organic nitrogen (POC/PON). In addition, dissolved and particulate trace metals, production, contaminants, dissolved organic carbon/total dissolved nitrogen (DOC/TDN) were determined in some cases. Benthic measurements were also collected, including benthic flux determinations (microcosm experiments), sediment characterisation, pore water chemistry measurements and the quantification of the benthic macrofauna. The coastal oceanographic data set was collected along the east coast of England between Great Yarmouth and Berwick upon Tweed. Data were collected between December 1992 and July 1995 during a series of 17 RRS Challenger cruise legs. Most cruises covered two survey grids: one from Great Yarmouth to the Humber designed around the distribution of the sandbanks and a second simple zig-zag grid from the Humber to Berwick on Tweed. A large number of anchor stations, usually over one or two tidal cycles, were worked in the vicinity of the Humber mouth or the Holderness coast. Each cruise leg returned underway data and conductivity-temperature-depth (CTD) data and water bottle rosette samples from grid nodes. A Lasentech in-situ particle sizer was used to obtain grain size distributions at spot depths for each CTD station on many of the cruise legs. Box and multicorer samples were collected on approximately one third of the cruise legs. The River-Atmosphere-Coast Study (RACS) was the component of the Land Ocean Interaction Study (LOIS) programme looking at processes from the river catchment into the coastal sea. Investigators include representatives of Plymouth University, Southampton University, Liverpool University, University of East Anglia, Newcastle University, Plymouth Marine Laboratory, and the University of Wales, Bangor. All data sets collected during the RACS Challenger cruises are held by the British Oceanographic Data Centre (BODC). All underway and CTD data have been fully calibrated and quality controlled by BODC. The water sample and benthic data sets have been quality controlled by the data originators and submitted to BODC. The data are held in the BODC project database and have been published as part of a fully documented CD-ROM product.

The dataset includes physical and biogeochemical measurements of water properties, meteorological data and biogeochemical measurements of sediment parameters. Temperature, salinity, turbidity, oxygen, nutrients, dissolved organic carbon/total dissolved nitrogen (DOC/TDN), particulate organic carbon/particulate organic nitrogen (POC/PON), contaminants and pH were measured at most of the data collection sites, with additional biogeochemical measurements collected at various locations. Temperature, salinity and nutrients are available for virtually all data collection campaigns. The data were collected in a number of estuaries around the UK between 1993 and 1997. The Humber estuarine data set was collected during a series of 33 campaigns on the EA vessels Sea Vigil and Water Guardian in the Humber, Trent and Ouse systems at approximately monthly intervals between June 1993 and December 1996. The measurements were taken over two or three one-day cruises that covered the estuary from the tidal limits of both Trent and Ouse to Spurn Point. Instrumental and sample data are available from a series of fixed stations that were sampled during every campaign. The Tweed estuarine data set was collected during a series of 13 campaigns using RV Tamaris and a rigid inflatable vessel at approximately monthly intervals between July 1996 and July 1997. Data were collected throughout the tidal reaches of the River Tweed. The dataset forms part of the NERC Land Ocean Interaction Study project. Key investigators for this LOIS sub-project included Plymouth Marine Laboratory. The data are held in the British Oceanographic Data Centre project database.

The dataset comprises physical, biogeochemical and biological oceanographic, surface meteorological and benthic measurements. Hydrographic profiles including temperature, salinity, fluorescence, transmissance and suspended sediment concentration were collected at numerous stations, while surface hydrographic (fluorescence, transmissance, sea surface temperature, salinity) and meteorological (irradiance, air temperature, humidity, wind speed/direction) data were collected across the survey areas. Sediment, pore water and water column samples were also collected for biogeochemical analysis, as were biological samples for the purposes of species classification and abundance analyses. The data were collected across the Indian Ocean, Arabian Sea and Pakistan margin areas between March and October 2003. Data collection was undertaken by the RRS Charles Darwin during four cruises: CD145 (12 March 2003 to 9 April 2003), CD146 (12 April 2003 to 30 May 2003), CD150 (22 August 2003 to 15 September 2003) and CD151 (17 September 2003 to 20 October 2003). Conductivity-temperature-depth (CTD) profilers with auxiliary sensors, benthic samplers and nets were deployed from the ship, while underway sensors provided continuous surface ocean, meteorological and bathymetric data. The study was designed to investigate an oxygen-minimum zone (OMZ) in the northern Arabian Sea. Chief Investigators include Gregory L Cowie (University of Edinburgh School of GeoSciences) and Brian J Bett (Southampton Oceanography Centre), while other institutions including the Dunstaffnage Marine Laboratory, University of Liverpool and Netherlands Institute of Ecology were also involved in the research. Data management is being undertaken by BODC. Some of the data are still undergoing processing at BODC and further data are expected from originators in the future.

This dataset includes physical, biological and biogeochemical measurements of both the water column and seabed sediments. Hydrographic data include temperature, salinity, attenuance, dissolved oxygen, fluorescence, photosynthetically active radiation (PAR), sound velocity and current velocities, while biogeochemical analyses of water samples provided measurements of nutrients and biological sampling provided measurements of zooplankton abundance. A large number of benthic parameters were measured, including concentrations of substances such as nutrients, metals and carbon in both sediments and sediment pore waters. Benthic fauna were also studied, while rates of sedimentation flux were quantified. These oceanographic and benthic data were supplemented by satellite ocean colour imagery. The data were collected in the North Atlantic Ocean at the Mouth of Rockall Trough, Hatton-Rockall Basin and the Flank of Feni Drift between August 1997 and June 1999 over four cruises, comprising a preliminary site assessment (CD 107 August, 1997) followed by two process cruises (CD 111, April-May 1998, and CD 113, June-July 1998). A further cruise (CH 143) was part-funded by BENBO to retrieve moorings. The data were collected using a variety of instrumentation, including shipboard deployment of conductivity-temperature-depth (CTD) profilers with attached auxiliary sensors, benthic samplers, landers, cameras and incubation chambers, water samplers and continuous underway sensors. These were supplemented by moored sensor and satellite data. The BENBO programme was led by the Scottish Association for Marine Science/Dunstaffnage Marine Laboratory involved researchers from Southampton Oceanography Centre, Scottish Universities Research and Reactor Centre, Plymouth Marine Laboratory, Lancaster University, Leeds University, Edinburgh University, Cambridge University and the University of Wales, Bangor.