Cruise inventory

RRS John Murray JM2/70

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS John Murray (74MJ)
Cruise identifierJM2/70
Cruise period1970-03-02 — 1970-03-07
Port of departureBarry, United Kingdom
Port of returnBarry, United Kingdom
ObjectivesThe purpose of the cruise was to test the spherical pressure vessels for the ocean bottom seismographs in deep water and to check the descent, bottom release, tracking and recovery of a twin sphere assembly which would hold a seismograph. All taks successfully accomplished.

A subsidiary purpose was to gain familiarity with the use of Ag/AgCl non-polarising electrodes in measuring potential gradients in the sea.
Chief scientistTim J G Francis (National Institute of Oceanography)
Cruise reportRRS John Murray JM2/70 cruise report john_murray2_70.pdf — access key 'C' (0.25 MB) 
Ocean/sea areas 
GeneralCeltic Sea
North East Atlantic Ocean (limit 40W)
SpecificCeltic Sea, North East Atlantic
Track chartsRRS John Murray JM2/70 cruise track — john_murray2_70trk.pdf (0.03 MB) 
Biology and fisheries 
Gear researchDescription: test spherical pressure vessels for ocean bottom seismographs in deep water
Geology and geophysics 
Other geological/geophysical measurementsQuantity: number of recoveries = 1
Description: dahn buoy recovered
Other geological/geophysical measurementsDescription: towing non-polarising electrodes
Other geological/geophysical measurementsQuantity: number of deployments = 1
Description: dahn buoy laid