Cruise inventory

RRS John Murray JM4/70 Leg 2

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS John Murray (74MJ)
Cruise identifierJM4/70 Leg 2
Cruise period1970-05-09 — 1970-05-20
StatusCompleted
Port of departureLa Rochelle, France
Port of returnBarry, United Kingdom
PurposeResearch
ObjectivesThe prupose of this cruise was:
1. Carry out a gravity survey in the SE corner of the Bay of Biscay
2. Reverse a refraction line.
3. Carry out a two ship seismic experiment with the Florence of the Institut Francais du Petrole, France.
4. To test a Lamont type airgun to carry out a controlled seismic reflection profile with airgun over a reversed refraction line.
Chief scientistF Gray (University of Cambridge Department of Earth Sciences)
Coordinating bodyNERC
Cruise reportRRS John Murray JM4/70 Leg 2 cruise report john_murray4_70.pdf — access key 'C' (0.28 MB) 
Ocean/sea areas 
GeneralBay of Biscay
SpecificBay of Biscay
Track chartsRRS John Murray JM4/70 Leg 2 cruise track — john_murray4_70trk.pdf (00 MB) 
Measurements 
Physical oceanography 
Surface drifters/drifting buoysQuantity: number of recoveries = 2
Description: dan buoy
Surface drifters/drifting buoysQuantity: number of deployments = 2
Description: dahn buoy
Geology and geophysics 
Gravity measurementsDescription: Askania gravimeter
Other geological/geophysical measurementsQuantity: number of experiments = 2
Description: shots using Aquaseis: 38 shots aquaseis at 2.5min intervals and 41 aquaseis at 1.5min
Other geological/geophysical measurementsQuantity: number of experiments = 2
Description: using Geophex: 30 shots at 8 minute intervals and 23 shots at 10 minute intervals