Sedimentology of cores from the shelf of Lazarev Sea, East Antarctica

DOI

Distinct facies types, classified in radiocarbon-dated sediments from the shelf of the Lazarev Sea, East Antarctica, reveal a detailed history of processes that have controlled sedimentation during the deglaciation over the last 10,000 yr. The ice retreat on this part of the Antarctic shelf started 9500 yr BP, marked by the deposition of laminated sediments, deposited from a floating ice shelf. These laminites, which occur on top of diamictons laid down from a grounded ice sheet, are the basal sediments of the postglacial sequence. The intensity of the Antarctic Coastal Current (ACC), directed by shelf morphology, controlled sedimentation of the postglacial facies. A residual glaciomarine sediment with the fine fraction winnowed by strong currents developed from 9000-8000 yr BP in the western part of the investigation area and from 9000-5000 yr BP in the eastern part, closer to the prominent 'Fenno Deep' trough. Current velocities apparently decreased between 8000 and 2000 yr BP due to a deflection of the ACC by advancing ice tongues to the east of the investigation area during the 'Hypsithermal'. This led to a deposition of fine-grained sediments, and clay mineralogy suggests a continental source, possibly near the grounding line of the Nivl Ice Shelf, rather than a winnowing of sediments near the shelf break or advection from deeper water. Current velocities intensified after 2000 yr BP, removed fine material from these sediments and led to a relict sediment, consisting of coarse bryozoan and molluscan debris.

Supplement to: Gingele, Franz; Kuhn, Gerhard; Maus, Bastian; Melles, Martin; Schöne, Tilo (1997): Holocene ice retreat from the Lazarev Sea shelf, East Antarctica. Continental Shelf Research, 17(2), 137-163

Identifier
DOI https://doi.org/10.1594/PANGAEA.726640
Related Identifier https://doi.org/10.1016/S0278-4343(96)00026-X
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.726640
Provenance
Creator Gingele, Franz; Kuhn, Gerhard ORCID logo; Maus, Bastian ORCID logo; Melles, Martin ORCID logo; Schöne, Tilo ORCID logo
Publisher PANGAEA
Publication Year 1997
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Language English
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 21 datasets
Discipline Earth System Research
Spatial Coverage (11.493W, -70.013S, 12.795E, -69.800N); Weddell Sea; Lazarev Sea
Temporal Coverage Begin 1991-02-21T15:27:00Z
Temporal Coverage End 1992-03-10T20:05:00Z