Cruise inventory

RRS Discovery D178

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Discovery (74E3)
Cruise identifierD178
Cruise period1988-11-08 — 1988-12-07
Port of departureViana do Castelo, Portugal
Port of returnGibraltar, Gibraltar
ObjectivesTo investigate the nature and crustal structure of the Madeira-Tores Rise in the vicinity of Josephine Seamount using:
1. A 250km long wide-angle seismic line recorded on six Cambridge digital ocean-bottom seismometers (DOBS), using closely spaced explosve charges and airgun shots.
2. A grid of underway single channel reflection, gravity, magnetic and bathymetry profiles in order to give regional control.
3. A test of the DOBS triggered mode, to monitor micro-earthquake activity on the sea bed.
4. Heat flow profiles.
Work was confined to a small area of international water between Portugal, Madeira and the Azores. Investigations concentrated on the Madeira-Tores Rise, the Horseshoe Abyssal Plain and the Ampere Seamount. Work was confined to a box delineated by 38N 15W, 39N 14W, 35N 12W, 34N 12W, 34N 12.5W, 37N 16W and to international waters within this box. The main DOBS/shot firing line ran between 35 37N 13 17W and 38 11N 14 53W.
Chief scientistPenny J Barton (University of Cambridge Department of Earth Sciences)
Cruise reportRRS Discovery D178 cruise report d178.pdf — access key 'C' (1.43 MB) 
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
SpecificMadeira - Tore Rise
Track chartsRRS Discovery D178 cruise track — trk3608.html
Physical oceanography 
BathythermographQuantity: number of profiles = 6
Other physical oceanographic measurementsQuantity: number of profiles = 1
Description: sound velocity
Geology and geophysics 
Single-beam echosoundingQuantity: track kilometres = 2850
Multichannel seismic reflectionQuantity: track kilometres = 1440
Seismic refractionQuantity: track kilometres = 270
Gravity measurementsQuantity: track kilometres = 2850
Magnetic measurementsQuantity: track kilometres = 1850
Other geological/geophysical measurementsQuantity: number of measurements = 24
Description: geothermy