RRS James Cook JC089
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS James Cook (740H) |
| Cruise identifier | JC089 |
| Cruise period | 2013-08-04 — 2013-08-27 |
| Status | Completed |
| Port of departure | Vigo, Spain |
| Port of return | Vigo, Spain |
| Purpose | Research |
| Objectives | JC089 set sail from Vigo, Spain, on 04 August 2013, two days behind schedule. The objective of the cruise was to collect geophysical data, water column samples, and sediment cores to support a proposal under consideration by the Integrated Ocean Drilling Program (IODP) to drill a series of sites on the SW Iberian Margin.
A total of 755 line kilometres of seismic reflection profiles were acquired using a three kilometre streamer and a small airgun source consisting of two generator-injector guns. There were significant problems with using two guns and the bulk of the survey was acquired using a single gun. Despite this problem together with weather downtime issues, data quality is generally good. Penetration of 3-4 seconds two-way travel time has been achieved at high fold with excellent resolution. The resulting set of crossing lines will provide an ideal basis for revising and resubmitting the IODP proposal which this cruise was designed to underpin. An important by-product of this seismic survey is imaging of the water column which has been calibrated by a combination of disposable hydrographic probes and CTD casts. Multibeam bathymetry and 3.5 kHz echosounder date were collected continuously during the seismic survey. 13 CTD casts were made using a trace metal free system to characterize the physical and chemical properties of water masses on the Iberian Margin, which will be used to interpret the water-column MCS profiles and for groundtruthing palaeoceanographic proxies in surface sediment. Water was collected at 13 stations using 10 liter Niskin bottles, totaling 246 bottles from which subsamples were taken for isotopic and elemental anlaysis.Sediment cores were acquired along a bathymetric transect ranging from 405 to 4670 m to meet IODP site survey requirements and study sediment processes (e.g., sediment provenance and focussing), bioturbation, and calibrate geochemical and sedimentological proxies on the Iberian Margin. A variety of coring systems were used including piston, Kasten, gravity, Megacore, and a grab sampler. Pore-water oxygen gradients were determined using micro-electrodes and interstitial waters were extracted from Megacore tubes at 1-cm intervals using Rhizon samplers (Rhizosphere Research Products, http://www.rhizosphere.com/). |
| Chief scientist | David Hodell (University of Cambridge Department of Earth Sciences) |
| Project | Integrated Ocean Drilling Program (IODP) |
| Cruise report |  (49.19 MB) (512.38 MB) |
| Ocean/sea areas | |
| General | North East Atlantic Ocean (limit 40W) |
| Specific | Promonotorio dos Principes de Avis on the southwestern Iberian Margin. |
| Track charts | (0.75 MB) |
| Measurements | |
| Physical oceanography | |
| Surface measurements underway (T,S) | Quantity: activity duration in days = 25 Description: Underway Surfnet Surface hydrography suite |
| Bathythermograph | Quantity: number of deployments = 108 Description: Subsurface measurements underway (96 XBTs and 12 XCTDs) |
| Water bottle stations | Quantity: number of stations = 13 Description: 13 Water bottle stations totalling 246 bottles |
| CTD stations | Quantity: number of deployments = 108 Description: Subsurface measurements underway (96 XBTs and 12 XCTDs) |
| CTD stations | Quantity: number of profiles = 13 Description: 13 CTD casts |
| Subsurface temperature and salinity measurements | Quantity: number of deployments = 108 Description: Subsurface measurements underway (96 XBTs and 12 XCTDs) |
| Current profiler (eg ADCP) | Quantity: activity duration in days = 25 Description: Underway vessel mounted ADCP |
| Meteorology | |
| Routine standard measurements | Quantity: activity duration in days = 25 Description: Underway Surfnet Meteorology suite |
| Geology and geophysics | |
| Grab | Quantity: number of samples = 1 Description: Grab sample |
| Core - soft bottom | Quantity: number of cores = 93 Description: 93 total Megacore tubes taken at 13 stations |
| Core - soft bottom | Quantity: number of cores = 10 Description: 10 Kasten cores totalling 35.9 meters of sediment |
| Core - soft bottom | Quantity: number of cores = 9 Description: 9 Piston cores totalling 80.8 meters of sediment |
| Core - soft bottom | Quantity: number of cores = 12 Description: 12 Box cores taken at 12 stations |
| Core - soft bottom | Quantity: number of cores = 4 Description: 4 Gravity cores totalling 20.15 meters of sediment |
| Geophysical measurements made at depth | Quantity: activity duration in days = 25 Description: SBP120 Sub Bottom Profiler |
| Single-beam echosounding | Quantity: activity duration in days = 25 Description: Single beam echosounder (EK60 Echo Sounder and Kongsberg EA600) |
| Multi-beam echosounding | Quantity: activity duration in days = 25 Description: Multibeam sonar (Kongsberg EM120) |
| Multichannel seismic reflection | Quantity: track kilometres = 755 Description: 755 line kilometres of seismic reflection profiles were acquired using a 3-km streamer and a small airgun source consisting of two generator-injector guns. |
| Gravity measurements | Quantity: activity duration in days = 25 Description: Gravity |
| Magnetic measurements | Quantity: track kilometres = 755 Description: Magnetics - magnetometer deployed during seismic survey |
| Other geological/geophysical measurements | Quantity: number of deployments = 6 Description: Stand-Alone Pumps (SAPs) |
