RRS James Clark Ross JR20090804 (JR175)
Cruise summary report
|Ship name (ship code)||RRS James Clark Ross (74JC)|
|Cruise identifier||JR20090804 (JR175)|
|Cruise period||2009-08-04 — 2009-09-11|
|Port of departure||Falmouth, United Kingdom|
|Port of return||Immingham, United Kingdom|
|Objectives||Marine geophysical and geological investigations of past flow and stability of a major Greenland ice stream in the late Quaternary
The aim of cruise JR175 to the West Greenland continental margin and Baffin Bay was to collect blocks of marine geophysical data using EM120 multibeam swath bathymetry and subbottom profiling, as well as transects of sediment cores using vibro-, box, and gravity coring from the continental shelf, slope and adjoining deep-sea basin offshore of Jakobshavns Isbrae in order to answer a number of scientific questions including:
- How long has this ice stream been in existence, what were its dimensions during past glaciations and particularly the LGM?
- When and how rapidly did it last retreat from the continental shelf of Greenland?
- What are the processes responsible for the high flow velocities of this ice stream and what are the major controls on its location?
- What is the nature of sedimentation associated with Jakobshavns Isbrae and has it undergone large-scale collapse prior to modern times?
|Chief scientist||Colm O'Cofaigh (University of Durham Department of Geography)|
|Cruise report||(1.06 MB)|
|General||The Northwestern Passages - Baffin Bay|
|Specific||West Greenland and Baffin Bay|
|Track charts||(00 MB)|
|Bathythermograph||Quantity: number of profiles = 33|
Description: XBTs collected for underway correction of EM120 multibeam swath bathymetry data
|CTD stations||Quantity: number of stations = 7|
Description: CTD stations.
|Geology and geophysics|
|Core - soft bottom||Quantity: number of cores = 55|
Description: 46 vibrocores (up to 6 m in length), 3 gravity cores (up to 6 m in length), 6 box cores (up to 0.49 m long)
|Multi-beam echosounding||Quantity: activity duration in days = 28|
Description: EM120 multibeam swath bathymetry data collection
|Other geological/geophysical measurements||Quantity: activity duration in days = 28|
Description: TOPAS sub-bottom profiler data collection