Abstract:
Dredge sampling was carried out aboard the James Clark Ross (cruise no JR77 ) during Feb and Mar 2004. The dredge target area was along the eastern segments of the West Scotia Ridge, an ocean spreading centre which stopped spreading about 10 million years ago. The spreading centre has high topographic relief and contains an axial rift, which has flanks that are suitable for dredging. The plan was to map the spreading centre using the swath bathymetry system, and then to use this map to locate the best dredging sites. Thirteen dredges were successful in recovering oceanic rocks of mixed sizes, up to and including very large boulders and dredge paths of up to 1 km were followed.
Keywords:
axial rift, dredge, global upper mantle fluxes, mantle domain boundary, mantle flow, mantle provenance, oceanic rock, peridotite, spreading centre
| Access Constraints: | Requests for data can be made via the UK Polar Data Centre (UK PDC) at BAS. |
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| Creation Date: | 2007-08-24 |
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| Dataset Progress: | Complete |
| Dataset Language: | English |
| ISO Topic Categories: |
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| Parameters: |
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| Personnel: | |
| Name | UK PDC |
| Role(s) | Metadata Author |
| Organisation | British Antarctic Survey |
| Name | Dr Tiffany Barry |
| Role(s) | Investigator |
| Organisation | The Open University |
| Name | Dr P Leat |
| Role(s) | Investigator |
| Organisation | British Antarctic Survey |
| Name | Dr I Millar |
| Role(s) | Investigator |
| Organisation | British Geological Survey |
| Name | Prof J Pearce |
| Role(s) | Investigator |
| Organisation | University of Cardiff |
| Parent Dataset: | N/A |
| Reference: | Pearce, J.A. & Stern, R.J., 2006. The origin of back-arc basin magmas: trace element and isotope perspectives. AGU Geophys. Monograph Series, 166, 63-86 Pearce J.A. 2005. Mantle Preconditioning by Melt Extraction during Flow: Theory and Petrogenetic Implications. J. Petrol. 48 , 973-998. Barry, T.L., Pearce, J.A., Leat, P.T., Millar, I.L. and A.P. le Roex. Hf isotope evidence for selective mobility of high-field-strength elements in a subduction setting: South Sandwich Islands. Earth and Planetary Science Letters, 252, 223-244. Barry, T.L., Pearce, J.A., Leat, P.T. and Millar, I.L. 2005. Some isotopic constraints on fluid versus melt transfer from slab to wedge: Hf isotope evidence from the South Sandwich Arc. Geochim. Cosmochim. Acta, 69, A634-A634. Leat, P.T., Pearce, J.A., Barker, P.F., Millar, I.L. and Larter, R.D. 2004. Magma genesis and mantle flow at a subducting slab edge: the South Sandwich arc-basin system. Earth and Planetary Science Letters, 227, 17-35. Pearce, J.A., Stern, R.J., Barry, T.L., Leat, P.T. and Millar, I.L. 2004. Geochemical tracing of mantle flow above subduction zones. EOS Trans. Amer. Geophys. Union, 80 (47), T23D-02. Leat, P.T., Pearce, J.A., Livermore, R. and Morris, P. 2004. Cruise Report: JR77 & JR78. AFI project no: AFI 02/36 Geochemical Tracing of Pacific-to-Atlantic Mantle Flow through the Drake Passage/Scotia Sea Gateway |
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| Lineage: | ||
| Temporal Coverage: | |
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| Start Date | 2004-02-19 |
| End Date | 2004-03-03 |
| Spatial Coverage: | |
| Latitude | |
| Southernmost | -58 |
| Northernmost | -54 |
| Longitude | |
| Westernmost | -55 |
| Easternmost | -40 |
| Altitude | |
| Min Altitude | N/A |
| Max Altitude | N/A |
| Depth | |
| Min Depth | N/A |
| Max Depth | N/A |
| Location: | |
| Location | Southern Ocean |
| Detailed Location | Drake Passage |
| Location | Southern Ocean |
| Detailed Location | Burdwood Fracture Zone |
| Location | Southern Ocean |
| Detailed Location | Scotia Sea |
| Location | Southern Ocean |
| Detailed Location | Lost Fracture Zone |
| Location | Southern Ocean |
| Detailed Location | Endurance Fracture Zone |
| Location | Southern Ocean |
| Detailed Location | Quest Fracture Zone |
| Distribution: | |
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| Distribution Media | Online FTP |
| Distribution Size | N/A |
| Distribution Format | N/A |
| Fees | See Natural Environment Research Council (NERC) Data Policy |
| Data Storage: | This data is managed by the UK Polar Data Centre (UK PDC) Geological Data Manager at BAS, and held on the BAS Storage Area Network (SAN). The geophysical data held for this and the linked datasets is: Multibeam swath bathymetry data, raw, processed and xyz formats, with a total storage of 17.6Gb, and TOPAS sub-bottom profiler data, 3Gb. |