Cruise inventory

RRS Discovery D16

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74E3)
Cruise identifierD16
Cruise period1967-01-20 — 1967-05-06
StatusCompleted
Port of departurePlymouth, United Kingdom
Port of returnPlymouth, United Kingdom
PurposeResearch
Objectives1. Stability trials of a one third scale model of GLORIA to be made on passage to Malta.
2. Seismic refraction stations and further gravity measurements to be made in the north end of the Red Sea and the Gulf of Aqaba.
3. Selected magnetic tracks to establish and map main E-W anomaly at Gulf of Aden.
4. Gulf of Aden - special area studies:-
(a) Survey and sampling programme in a one degree square in the Central Rough Zone.
(b) Survey programme in sediment filled south main trough.
(c) Dredging and seismic programme on cliffs and flanks of Alula-Fartak trench where gravity measurements have indicated high density rocks near the surface.
5. To survey magnetic and topographic lineations as far as possible in towards Afar depression and to sample exposures on cliffs.
6. Seismic refraction stations to determine crustal structure and nature and depth of Moho boundary.
7. Topographic, magnetic and gravity survey to determine the nature of the connection between the central rough zone of the Gulf of Aden and the Owen fracture zone with special reference to the epicentre belt.
8. Topographic and seismic reflection survey to determine direction of continuity (if any) of the fracture zone and whether the Somali Basin was at one time enclosed.
9. Samples obtained in 1963 in area 40 showed variable composition over short ranges. Dredging, coring, grabbing, photography and water sampling planned in relation to topography.
10. Chemical and thermal structure in bottom 200 metres to be studied with closely spaced water bottles and continuous temperature recorder.
11. Simultaneous measurement of temperature gradients above and below the sediment-water interface.
12. Sampling programme of sediment and bottom water in the deep holes along the Red Sea rift for geochemical studies.
Chief scientistAnthony S Laughton (National Institute of Oceanography)
Cruise reportRRS Discovery D16 cruise report d16.pdf — access key 'C' (1.15 MB) 
Ocean/sea areas 
GeneralRed Sea
Gulf of Aden
SpecificRed Sea, Gulf of Aden,
Track chartsRRS Discovery D16 cruise track — d16track.pdf (00 MB) 
Measurements 
Physical oceanography 
Water bottle stationsQuantity: number of stations = 5
Description: water bottle stations for pH, salinity, dissolved oxygen and silicate analyses.
Chemical oceanography 
OxygenQuantity: number of stations = 5
Description: water bottle stations for pH, salinity, dissolved oxygen and silicate analyses.
SilicateQuantity: number of stations = 5
Description: water bottle stations for pH, salinity, dissolved oxygen and silicate analyses.
pHQuantity: number of stations = 5
Description: water bottle stations for pH, salinity, dissolved oxygen and silicate analyses.
Biology and fisheries 
Gear researchDescription: GLORIA model trials.
Geology and geophysics 
DredgeQuantity: number of deployments = 20
GrabQuantity: number of samples = 2
Core - soft bottomQuantity: number of cores = 7
Bottom photographyQuantity: number of stations = 2
Single channel seismic reflectionQuantity: 5
Description: Airgun seismic reflection profiles.
Seismic refractionQuantity: 12