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

Cruise inventory

Surveyor 71/1 Leg 3

Cruise summary report

Cruise Info. 
Ship nameSurveyor
Cruise identifier71/1 Leg 3
Cruise period1971-03-31 — 1971-04-11
Port of departureStornoway, United Kingdom
Port of returnBarry, 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.

After some initial equipment problems the PES fish was streamed. Surveyor then steamed to the position of tide gauge 2. The gauge was tracked overnight but without success but when the internal pinger was switched on the gauge was located easily and recovered. The ship then proceeded to the site of tide gauge 1 after a period of dragging the tide gauge was recovered. Stations 106 - 184 dredging from St Kilda southwards towards Malin Head. At each station 2 grab samples were normally taken using the 01.1m2 Smith McIntyre grab. If there was shelly material present then the rock dredge was used.

1. 2 tide gauges successfully recovered.
2. Samples of living and dead benthic fauna were obtained from 78 stations.
3. NIO transistored precision-echo-sounder system was used
Chief scientistJohn B Wilson (National Institute of Oceanography)
Cruise reportSurveyor 71/1 Leg 3 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 3 cruise track — surveyor_feb71track.pdf (0.06 MB) 
Biology and fisheries 
Sediment trapsQuantity: number of stations = 78
Description: bottom sediment samples collected
Geology and geophysics 
DredgeQuantity: number of stations = 78
Description: benthic faunal samples taken
GrabQuantity: number of stations = 78
Description: benthic faunal samples taken
In-situ seafloor measurement/samplingQuantity: number of stations = 78
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 was recovered from 102m depth.
Other physical oceanographic measurements58° 3' 59" N  8° 33' 0" W — tide gauge recovered from 49m depth