Planned maintenance — 18th January 2018 12:00 to 22nd January 2018 09:00 [more]

Cruise inventory

Surveyor 71/1 Leg 1

Cruise summary report

Cruise Info. 
Ship nameSurveyor
Cruise identifier71/1 Leg 1
Cruise period1971-02-26 — 1971-03-08
Port of departureBarry, United Kingdom
Port of returnStornoway, United Kingdom
ObjectivesTide Gauges - Geology and geophysics on the Hebridean Shelf and on the Rockall Plateau

1. To obtain a months continuous tide record on the outer part of the shelf as part of a continuing programme of tide and current observations.
2. To compare the living faunal distribution with that deduced from the biogenic carbonate fraction of the sediments and to investigate the processes involved in its production.

The PES fish was streamed in the North Channel and acoustic tests were carried out on the 2 NIO tide gauges. Magnetometer was streamed and tested. The laying of the first tide gauge was delayed by bad weather, laid at 58° 03.9'N 08° 32.6'W at a depth of 27 fathoms. Further acoustic test on tide gauge 2 revealed a fault, this was repaired whilst grab station 1 was worked. The second tide gauge was laid successfully at 58° 46.1'N 07° 30.3W at 56 fathoms depth. The remainder of the leg was devoted to bottom sediment and faunal sampling using the 0.1m2 Smith McIntyre grab and rock dredge. Samples collected from 57 stations on the Hebridean Shelf north of St Kilda, at each station 2 grab samples were normally taken .

1. 2 tide gauges successfully deployed.
2. Samples of living and dead benthic fauna were obtained from 57 stations.
3. Total magnetic field - short traverse was made to test the equipment.
Chief scientistJohn B Wilson (National Institute of Oceanography)
Cruise reportSurveyor 71/1 Leg 1 cruise report surveyor_feb71.pdf — access key 'C' (0.77 MB) 
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
Track chartsSurveyor 71/1 Leg 1 cruise track — surveyor_feb71track.pdf (0.06 MB) 
Biology and fisheries 
Sediment trapsQuantity: number of stations = 57
Description: bottom sediment samples collected
Geology and geophysics 
DredgeQuantity: number of stations = 57
Description: benthic faunal samples taken
GrabQuantity: number of stations = 57
Description: benthic faunal samples taken
In-situ seafloor measurement/samplingQuantity: number of stations = 57
Description: bottom sediment samples collected
Multi-beam echosoundingQuantity: number of measurements = 1
Description: acoustic tests
Moorings, landers, buoys 
Physical oceanography 
Other physical oceanographic measurements58° 45' 59" N  7° 30' 0" W — tide gauge deployed at 102m depth
Other physical oceanographic measurements58° 3' 59" N  8° 33' 0" W — deployment of tide gauge at a depth 49m