RV Farnella 4/81
Cruise summary report
|Ship name (ship code)||RV Farnella (74AE)|
|Cruise period||1981-11-28 — 1981-12-19|
|Port of departure||Ponta Delgada, Portugal|
|Port of return||Belem, Brazil|
|Objectives||1. To lay tide gauges at seven locations along the Mid-Atlantic Ridge between the Azores and South America.
2. To run GLORIA and other geophysical equipment between the tide-gauge deployments, with the following objectives:
(a) To determine the separation direction of the North American and African plates at several points along the Mid-Atlantic Ridge by mapping the precise locations and directions of several large-offset transform faults,
(b) To measure the ratio of inward to outward facing fault scarps near the Mid-Atlantic Ridge.
(c) To investigate the extension of Fifteen Twenty fracture zone and the possible North America/South America plate boundary west of the Mid-Atlantic Ridge.
(d) To study how fracture zone morphology is affected by spreading direction changes.
(e) To obtain some GLORIA runs over Vema fracture zone.
All the aims were successfully achieved with the exception of (d) and (e).
|Chief scientist||Roger C Searle (Institute of Oceanographic Sciences Wormley Laboratory)|
|Cruise report||(0.45 MB)|
|General||North West Atlantic Ocean (limit 40W)|
|Sea level (inc. bot. press., inverted echosounder)||Quantity: 7|
Description: 7 deepsea tide gauges between 3066 and 4850 m
|Geology and geophysics|
|Multi-beam echosounding||Quantity: track kilometres = 6482|
|Long/short range side scan sonar||Quantity: track kilometres = 5556|
|Single channel seismic reflection||Quantity: track kilometres = 1482|
|Gravity measurements||Quantity: track kilometres = 8334|
|Magnetic measurements||Quantity: track kilometres = 5926.4|