Cruise inventory

RRS James Clark Ross JR20080823 (JR211)

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS James Clark Ross (74JC)
Cruise identifierJR20080823 (JR211)
Cruise period2008-08-23 — 2008-09-24
StatusCompleted
Port of departureLongyearbyen, Svalbard and Jan Mayen
Port of returnImmingham, United Kingdom
PurposeResearch
ObjectivesThe cruise, which was part of the International Polar Year programme, investigated evidence for the existence of methane hydrate in the sediment of the continental margin of northwestern Svalbard, and evidence for the escape of methane gas released by the hydrate into the water column during the period following the last glaciation to the present day (approximately 15,000 years). It used geophysical and geological techniques to detect methane hydrate beneath the seabed, discovered and sampled features through which methane escapes to the seafloor, and measured methane concentration in the water column and the atmosphere.

The seabed was imaged and mapped using multibeam sonar (Simrad EM120), Simrad EK60 echo sounder, TOBI deep-towed sidescan sonar (30 kHz), and Widescan sidescan sonar (100 and 325 kHz). The sedimentary layers and geological structures beneath the seabed were imaged with the 7kHz profiler in TOBI, a TOPAS sub-bottom acoustic profiler and multichannel seismic reflection (96 channels with 6.25-metre group spacing) using two GI guns in true GI mode 45/105 cu. In. More accurate information on seismic velocity will be obtained by deploying 4 ocean-bottom seismometers on the seabed for two or three days at a time. Samples of sediment, two of them containing hydrate, were taken, using piston corer, gravity corer and box corer.

Water chemistry was measured from samples taken with bottles attached to ctds and continuously from the ship using the uncontaminated seawater supply. Air samples were taken.
Chief scientistGraham K Westbrook (University of Birmingham School of Geography, Earth and Environmental Sciences)
ProjectIPY - Gas Hydrates
Cruise reportRRS James Clark Ross JR20080823 (JR211) cruise report jr211.pdf — access key 'C' (126.75 MB) 
Ocean/sea areas 
GeneralArctic Ocean
SpecificArctic Ocean
Track chartsRRS James Clark Ross JR20080823 (JR211) cruise track — jr211trk.pdf (00 MB) 
Measurements 
Physical oceanography 
Surface measurements underway (T,S)Quantity: track kilometres = 6437
Description: Underway measurements of temperature, salinity
Water bottle stationsQuantity: number of stations = 13
Description: 24-bottle rosette
CTD stationsQuantity: number of stations = 13
Description: CTD
Chemical oceanography 
Other chemical oceanographic measurementsQuantity: number of measurements = 1100
Description: Flux of methane and carbon dioxide from surface seawater to air, using an automated equilibrator and Gas Chromatograph
Meteorology 
Atmospheric chemistryQuantity: number of samples = 83
Description: 5-litre samples of air taken to measure methane concentration.
Atmospheric chemistryQuantity: number of measurements = 1100
Description: Flux of methane and carbon dioxide from surface seawater to air, using an automated equilibrator and Gas Chromatograph
Geology and geophysics 
Core - soft bottomQuantity: number of cores = 33
Description: 16 box cores, 15 gravity cores, 2 piston cores
Single-beam echosoundingQuantity: track kilometres = 5300
Description: SIMRAD EK60 multi-frequency single-beam sonar (echo-sounder), SIMRAD TOPAS parametric sub-bottom profiler
Multi-beam echosoundingQuantity: track kilometres = 5300
Description: SIMRAD EM120 multibeam echo sounder
Long/short range side scan sonarQuantity: track kilometres = 58
Description: Widescan 100 and 325 kHz deep-towed sonar with total swath widths of 200, 400 and 800 m
Long/short range side scan sonarQuantity: track kilometres = 249
Description: TOBI 30 kHz deep-towed sonar with maximum total swath width of 6 km
Multichannel seismic reflectionQuantity: track kilometres = 1180
Description: Streamer: 96-channel, 6.25-m group spacing, Two GI guns 45/105 cu. in.
Other geological/geophysical measurementsQuantity: number of deployments = 13
Description: 13 4-component (hydrophone and 3 orthogonal geophones) ocean-bottom seismometers deployed at 5 locations.
Data held at BODC 
Series/Profiles 
1  Single-beam echosounder
Bathymetry and Elevation
Horizontal spatial co-ordinates
Reference numbers
Bathymetry and Elevation
Horizontal spatial co-ordinates
Reference numbers

BODC idDate/TimeLocationDoc.
11713132008-08-23 00:00  — 2008-09-24 00:00 77° 34' 59" N  5° 3' 12" E — 80° 0' 50" N  10° 4' 57" E  View metadata report for BODC series reference number 1171313
Discrete samples 
65  Atmospheric air sampling pumpConcentration of alkanes in the atmosphere
Stable isotope enrichment in the atmosphere
6  Box coreConcentration of inorganic halogens in sediment pore waters
Sediment water content, porosity and surface area
Trace metalloid concentrations in sediment pore water
Metal concentrations in sediment pore waters
Concentration of inorganic sulphur species in sediment pore water
Carbonate chemistry in sediment pore waters
Concentration of aliphatic hydrocarbons in sediment samples
Dissolved concentration parameters for other gases in sediment pore waters
11  CTD frame plus rosette samplerConcentration of alkanes in the water column
Dissolved oxygen parameters in the water column
4  Gravity CorerConcentration of inorganic halogens in sediment pore waters
Sediment water content, porosity and surface area
Stable isotope enrichment in sediment
Trace metalloid concentrations in sediment pore water
Metal concentrations in sediment pore waters
Concentration of inorganic sulphur species in sediment pore water
Carbonate chemistry in sediment pore waters
Concentration of aliphatic hydrocarbons in sediment samples
Dissolved concentration parameters for other gases in sediment pore waters
1  Piston corerConcentration of inorganic halogens in sediment pore waters
Sediment water content, porosity and surface area
Trace metalloid concentrations in sediment pore water
Metal concentrations in sediment pore waters
Concentration of inorganic sulphur species in sediment pore water
Carbonate chemistry in sediment pore waters
Concentration of aliphatic hydrocarbons in sediment samples
Dissolved concentration parameters for other gases in sediment pore waters