Planned maintenance — 18th January 2018 12:00 to 22nd January 2018 09:00 [more]

Cruise inventory

RRS John Murray JM9/79

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS John Murray (74MJ)
Cruise identifierJM9/79
Cruise period1979-06-29 — 1979-07-12
ObjectivesThe most important objective of the cruise was to detonate explosive charges for the South West England Seismic Experiment. Charges were detonated at the southernmost (or easternmost) point of six lines across S.W. England , and also at ten points along a line between the Lizard and Start. Because of a timing transmission breakdown, one shot had to be repeated, and in all some 37 shots were successfully detonated with no misfures. Charge sizes ranged from 100m to 800m of 'Superflex' and for the larger charges (400m+) line charges were streamed in parallel so that the charge length was never longer than 300m. Not one of the charges 'blew out'. Wherever possible, shot points were checked for fish kill.
Chief scientistP Neil Chroston (University of East Anglia School of Environmental Sciences)
ProjectSouthwest England Seismic Experiment (SWESE)
Cruise reportRRS John Murray JM9/79 cruise report john_murray9_79.pdf — access key 'C' (0.23 MB) 
Ocean/sea areas 
GeneralEnglish Channel
Track chartsRRS John Murray JM9/79 cruise track — trk2629.html
Geology and geophysics 
Single channel seismic reflectionQuantity: track kilometres = 1482
Seismic refractionQuantity: number of deployments = 45
Magnetic measurementsQuantity: track kilometres = 370.4
Description: seismic shots were fired for crews recording on land