RRS Charles Darwin CD102
Cruise summary report
|Ship name (ship code)||RRS Charles Darwin (74AB)|
|Cruise period||1996-09-05 — 1996-10-03|
|Port of departure||Ponta Delgada, Portugal|
|Port of return||Ponta Delgada, Portugal|
|Objectives||There were two objectives of this cruise. The first was to recover eight moorings that were deployed in August 1995 as part of the BRIDGE "FLUXES" programme. This programme sought to examine segment scale processes within the Broken Spur Vent Field segment of the Mid-Atlantic Ridge at 29degN, 43degW. Four days were allocated for the recovery operations, which allowed for their depth, complexity and possibilities of dragging for failed releases. The moorings all had single top-sided buoyancy followed by strings of various current meters, thermistors and thermistor chains and, on three of the eight, sediment traps. The longest mooring was 1500m and the shortest was 200m. The second object of the cruise was to recover sediments by coring in order to determine the relationship between microbial activity and diagenesis in metalliferous hydrothermal sediments using the following techniques:
1) To collect hydrothermal sediments from the MIR mounds in the TAG hydrothermal area using a variety of coring techniques (gravity corer, box corer and multi corer).
2) To extract porewaters from these sediments for on board analysis of nutrients and trace element analysis on archived samples on return to the UK.
3) To prepare core materials for microbiological analysis on board (flux measurements) and on material returned to Bristol (incubation experiments, MPN, etc.).
4) To preserve the solid phase in a form that would allow detailed geochemical and mineralogical analysis of the material on return to Bristol.
The research to be undertaken as a result of this cruise built on the results of previous BRIDGE cruises to the TAG area by members of CD102 and other UK and overseas scientists.
|Chief scientist||Martin R Palmer (University of Bristol Geology Department)|
|Cruise report||(1.58 MB)|
|General||North Atlantic Ocean|
|Specific||Mid Atlantic Ridge|
|Subsurface temperature and salinity measurements||Quantity: number of samples = 2|
Description: 2 surface water samples
|Subsurface temperature and salinity measurements||Quantity: number of measurements = 1|
Description: 1 swath bathymetry profile
|Current meters||Quantity: number of recoveries = 8|
Description: 8 moooring recoveries from various stations.
|Other physical oceanographic measurements||Quantity: number of deployments = 5|
Description: 5 transponder net deployments
|Other physical oceanographic measurements||Quantity: number of measurements = 1|
Description: 1 sound velocity profile
|Geology and geophysics|
|Core - soft bottom||Quantity: number of cores = 58|
Description: 58 3m gravity cores
|Core - soft bottom||Quantity: number of cores = 7|
Description: 7 multi corer
|Core - soft bottom||Quantity: number of cores = 2|
Description: 2 2m Gravity Cores
|Core - soft bottom||Quantity: number of cores = 6|
Description: 1m Gravity core
|Core - soft bottom||Quantity: number of cores = 16|
Description: 16 Box cores