Sedimentology of surface samples from the Weddell Sea, Antarctica

DOI

Mineralogical and granulometric properties of glacial-marine surface sediments of the Weddell Sea and adjoining areas were studied in order to decipher spatial variations of provenance and transport paths of terrigenous detritus from Antarctic sources. The silt fraction shows marked spatial differences in quartz contents. In the sand fractions heavy-mineral assemblages display low mineralogical maturity and are dominated by garnet, green hornblende, and various types of clinopyroxene. Cluster analysis yields distinct heavy-mineral assemblages, which can be attributed to specific source rocks of the Antarctic hinterland. The configuration of modern mineralogical provinces in the near-shore regions reflects the geological variety of the adjacent hinterland. In the distal parts of the study area, sand-sized heavy minerals are good tracers of ice-rafting. Granulometric characteristics and the distribution of heavy-mineral provinces reflect maxima of relative and absolute accumulation of ice-rafted detritus in accordance with major iceberg drift tracks in the course of the Weddell Gyre. Fine-grained and coarse-grained sediment fractions may have different origins. In the central Weddell Sea, coarse ice-rafted detritus basically derives from East Antarctic sources, while the fine-fraction is discharged from weak permanent bottom currents and/or episodic turbidity currents and shows affinities to southern Weddell Sea sources. Winnowing of quartz-rich sediments through intense bottom water formation in the southern Weddell Sea provides muddy suspensions enriched in quartz. The influence of quartz-rich suspensions moving within the Weddell Gyre contour current can be traced as far as the continental slope in the northwestern Weddell Sea. In general, the focusing of mud by currents significantly exceeds the relative and absolute contribution of ice-rafted detritus beyond the shelves of the study area.

Supplement to: Diekmann, Bernhard; Kuhn, Gerhard (1999): Provenance and dispersal of glacial-marine surface sediments in the Weddell Sea and adjoining areas, Antarctica: ice-rafting versus current transport. Marine Geology, 158(1-4), 209-231

Identifier
DOI https://doi.org/10.1594/PANGAEA.730459
Related Identifier https://doi.org/10.1016/S0025-3227(98)00165-0
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.730459
Provenance
Creator Diekmann, Bernhard ORCID logo; Kuhn, Gerhard ORCID logo
Publisher PANGAEA
Publication Year 1999
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 3 datasets
Discipline Earth System Research
Spatial Coverage (-69.049W, -78.262S, 37.480E, -48.723N); Southern Ocean; Filchner Trough; Filchner Shelf; King George Island, Antarctic Peninsula; South Orkney; Weddell Sea; Bransfield Strait; Halley Bay; Gould Bay; Camp Norway; Atka Bay; Lyddan Island; Eastern Weddell Sea, Southern Ocean; Kapp Norvegia; Cape Fiske; Maud Rise; Argentine Islands; Vestkapp; Barents Sea; Hope Bay; Drake Passage; Antarctic Peninsula; Adelaide Island; Anvers Island; Wegener Canyon; Fram Strait; Greenland Slope; Lazarev Sea; Astrid Ridge; Polarstern Kuppe; South Atlantic; South Atlantic Ocean; Scotia Sea, southwest Atlantic; Islas Orcadas; Riiser-Larsen Sea; Cosmonauts Sea
Temporal Coverage Begin 1983-02-13T00:00:00Z
Temporal Coverage End 1997-03-03T15:38:00Z