Cruise inventory

RRS Discovery D331T

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74E3)
Cruise identifierD331T
Cruise period2008-07-24 — 2008-08-15
StatusCompleted
Port of departurePortland Harbour, United Kingdom
Port of returnSt John, Canada
PurposeResearch
ObjectivesThis was the second cruise undertaken to the Mid-Atlantic Ridge as part of the NERC-funded consortium project (NE/C512961/1) entitled ECOMAR - Ecosystem of the Mid-Atlantic Ridge at the Sub-Polar Front and Charlie Gibbs Fracture Zone. ECOMAR - Ecosystem of the Mid-Atlantic Ridge at the Sub-Polar Front and Charlie Gibbs Fracture Zone.(http://www.oceanlab.abdn.ac.uk/ecomar/index.php)

ECOMAR forms part of the Census of Marine Life MAR-ECO project which is an international study of life in the northern mid-Atlantic Ocean with scientists from 16 nations participating in research of the waters around the mid-Atlantic Ridge from Iceland to the Azores (http://www.mar-eco.no). ECOMAR is focussed on patterns and processes in an area approximately half way between Iceland and the Azores in the vicinity of the Charlie-Gibbs Fracture Zone. The fracture zone represents a major discontinuity in the structure of the ridge but is also the latitude at which the north Atlantic current crosses the ridge from west to east delineating the position of the sub-polar front with cooler productive waters to the north and warmer more oligotrophic to the south. A voyage of the RV GO Sars in 2004 had indicated important differences in fauna across this boundary.

The first cruise in the ECOMAR series (JC 11) established a detailed bathymetric survey of the 4 sites, deployed long-term moorings at each ECOMAR site, and carried out a series of scientific surveys to build up an understanding of the physical, chemical, and biological characteristics of the area.

The second cruise (D331) in the ECOMAR series was meant to continue the detailed scientific survey work and recover, service and redeploy each of the long-term moorings. However, due to the Discovery's extended refit the second cruise was reduced to a trials cruise (D331T) with the specific objectives of:
- Recovering, servicing, and redeploying each of the four ECOMAR moorings situated at SE, SW, NE, & NW mooring sites;
- Recover, service and redeploy the DOBO Lander;
- Recover, and redeploy the ECOMAR Bathysnap Lander;
- Recover the PAP Bathysnap Lander;
- Perform winch trials.

Due to the reduction of D331 to a trials cruise, the remaining ECOMAR cruise programme will be altered to allow research cruises in summer 2009 (RRS James Cooke), and a further cruise in 2010 with the ISIS ROV (RRS James Cook).
Chief scientistPhilip Bagley (University of Aberdeen, Oceanlab)
ProjectECOMAR
Coordinating bodyUniversity of Aberdeen, Oceanlab
Cruise reportRRS Discovery D331T cruise report d331t.pdf — access key 'C' (7.71 MB) 
Ocean/sea areas 
GeneralNorth Atlantic Ocean
SpecificMid-Atlantic Ridge around the Charlie Gibbs fracture zone
Track chartsRRS Discovery D331T cruise track — d331ttrk.pdf (00 MB) 
Measurements 
Physical oceanography 
CTD stationsQuantity: number of profiles = 4
Description: One CTD taken at each of the 4 mooring locations prior to mooring deployment
Moorings, landers, buoys 
Physical oceanography 
Current meters49° 2' 35" N  27° 43' 30" W — SE Mooring (Sediment trap & current meters)
Current meters53° 59' 17" N  36° 7' 23" W — NW Mooring (Sediment traps & current meters)
Current meters54° 0' 0" N  34° 10' 35" W — NE Mooring (Sediment traps, current meters, & ADCP)
Current meters48° 46' 48" N  28° 38' 24" W — SW Mooring (Sediment trap & current meters)
Current profiler (eg ADCP)54° 0' 0" N  34° 10' 35" W — NE Mooring (Sediment traps, current meters, & ADCP)
Biology and fisheries 
Sediment traps54° 0' 0" N  34° 10' 35" W — NE Mooring (Sediment traps, current meters, & ADCP)
Sediment traps48° 46' 48" N  28° 38' 24" W — SW Mooring (Sediment trap & current meters)
Sediment traps49° 2' 35" N  27° 43' 30" W — SE Mooring (Sediment trap & current meters)
Sediment traps53° 59' 17" N  36° 7' 23" W — NW Mooring (Sediment traps & current meters)
Other biological/fisheries measurement54° 1' 29" N  34° 10' 35" W — NE Whale bone
Other biological/fisheries measurement53° 59' 17" N  36° 11' 42" W — NW Whale bone