RRS Discovery D178
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS Discovery (74E3) |
| Cruise identifier | D178 |
| Cruise period | 1988-11-08 — 1988-12-07 |
| Status | Completed |
| Port of departure | Viana do Castelo, Portugal |
| Port of return | Gibraltar, Gibraltar |
| Purpose | Research |
| Objectives | To 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 scientist | Penny J Barton (University of Cambridge Department of Earth Sciences) |
| Cruise report |  (1.43 MB) |
| Ocean/sea areas | |
| General | North East Atlantic Ocean (limit 40W) |
| Specific | Madeira - Tore Rise |
| Track charts |  |
| Measurements | |
| Physical oceanography | |
| Bathythermograph | Quantity: number of profiles = 6 |
| Other physical oceanographic measurements | Quantity: number of profiles = 1 Description: sound velocity |
| Geology and geophysics | |
| Single-beam echosounding | Quantity: track kilometres = 2850 |
| Multichannel seismic reflection | Quantity: track kilometres = 1440 |
| Seismic refraction | Quantity: track kilometres = 270 |
| Gravity measurements | Quantity: track kilometres = 2850 |
| Magnetic measurements | Quantity: track kilometres = 1850 |
| Other geological/geophysical measurements | Quantity: number of measurements = 24 Description: geothermy |
