RRS James Cook JC132

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS James Cook (740H)
Cruise identifierJC132
Cruise period2016-01-14 — 2016-02-24
Port of departureMindelo, Cape Verde
Port of returnPort of Spain, Trinidad and Tobago
ObjectivesThe primary objective of RRS James Cook cruise JC132 was to acquire the active-source geophysical data and seafloor imagery to complement the passive recordings of microseisms made by 25 ocean-bottom seismographs (OBS) deployed at the 13°20'N oceanic core complex on the Mid-Atlantic Ridge during JC102 and recovered during JC109.
Four main data types were collected during JC132: wide-angle recordings of airgun shots by up to 58 OBS; multichannel seismic (MCS) reflection data recorded by a 3 km streamer and airgun sources; near seafloor magnetic data and seafloor imagery recorded by Autosub. Gravity and swath bathymetry data were also acquired port-to-port. The swath bathymetry data were calibrated with a sound velocity dip undertaken at the lateral centre of the ocean-bottom seismograph grid; in the same location as sampled during JC102 and JC109.
Good quality near-seabed bathymetry and magnetic data, and both wide-angle refraction and normal incidence reflection seismic data were acquired throughout the cruise with which to address the science objectives.
Chief scientistChristine Peirce (University of Durham, Department of Earth Sciences), Timothy Reston (University of Birmingham School of Geography, Earth and Environmental Sciences)
ProjectThe Role and Extent of Detachment Faulting at Slow-Spreading Mid-Ocean Ridges
Coordinating bodyNatural Environment Research Council (NERC)
Cruise reportRRS James Cook JC132 cruise report jc132.pdf (130.18 MB) 
Ocean/sea areas 
GeneralNorth Atlantic Ocean
SpecificCentral Atlantic
Track chartsRRS James Cook JC132 cruise track — jc132trk.pdf (0.15 MB) 
Physical oceanography 
Other physical oceanographic measurementsQuantity: number of deployments = 3
Description: Sound velocity / temperature vs depth in three locations.
Geology and geophysics 
Multi-beam echosoundingQuantity: activity duration in days = 42
Description: Swath bathymetry during all seismic profiles and during transit to-from the work area
Multichannel seismic reflectionQuantity: number of profiles = 27
Description: Multichannel seismic data between 13 40N - 12 00N; 44 30 - 45 30 W
Seismic refractionQuantity: number of deployments = 68
Description: Ocean bottom seismograph
Gravity measurementsQuantity: activity duration in days = 42
Description: Gravity run continuously from Cape Verde to study area to Trinidad
Magnetic measurementsQuantity: number of profiles = 1
Description: Magnetics recorded during multichannel seismic profiles (G76) and from AUV (G90) near-seafloor transects
Other geological/geophysical measurementsQuantity: number of profiles = 1
Description: Eh, Turbidity, microbathymetry and near seafloor magnetics collected by AUV Autosub 6000 in work area around 13 20'N
Data held at BODC Get data
Discrete samples 
3  Sound Velocity Probe