RRS Discovery D171
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS Discovery (74E3) |
| Cruise identifier | D171 |
| Cruise period | 1987-10-23 — 1987-11-27 |
| Status | Completed |
| Port of departure | Barry, United Kingdom |
| Port of return | Nassau, Bahamas |
| Purpose | Research |
| Objectives | The objectives of this cruise were to return to an area of the Mesozoic North Atlantic where an earlier reconnaissance multichannel seismic profile had imaged reflectors within the oceanic crust, and to make a detailed seismic survey of the area. In particular, we were to use two-ship expanding spread profiles (ESP's) to determine the velocity structure of the crust and hence to identify the main reflectors seen on normal incidence seismic reflection profiles.
We planned to work across a normal ribbon of oceanic crust and the adjacent small-offset Blake-Spur fracture zone so as to investigate the structure of both normal oceanic crust and fracture zone crust. We used two research ships each equipped with multichannel seismic systems, the RRS Discovery and RV Conrad. The project was run jointly between Cambridge and the University of Rhode Island. |
| Chief scientist | Robert S White (University of Cambridge Department of Earth Sciences) |
| Cruise report |  (0.95 MB) |
| Ocean/sea areas | |
| General | North West Atlantic Ocean (limit 40W) |
| Track charts |  |
| Measurements | |
| Physical oceanography | |
| Bathythermograph | Quantity: number of profiles = 6 |
| Geology and geophysics | |
| Multi-beam echosounding | Quantity: track kilometres = 4074 |
| Single channel seismic reflection | Quantity: 400 |
| Seismic refraction | Quantity: track kilometres = 1111 |
| Gravity measurements | Quantity: track kilometres = 4074 |
| Magnetic measurements | Quantity: track kilometres = 4074 |
