Geochemistry and age determination of zircons in Cretaceous to Quaternary sediments

DOI

In central Antarctica, drainage today and earlier back to the Paleozoic radiates from the Gamburtsev Subglacial Mountains (GSM). Proximal to the GSM past the Permian-Triassic fluvial sandstones in the Prince Charles Mountains (PCM) are Cretaceous, Eocene, and Pleistocene sediment in Prydz Bay (ODP741, 1166, and 1167) and pre-Holocene sediment in AM04 beneath the Amery Ice Shelf. We analysed detrital zircons for U-Pb ages, Hf-isotope compositions, and trace elements to determine the age, rock type, source of the host magma, and "crustal" model age (T(C)DM). These samples, together with others downslope from the GSM and the Vostok Subglacial Highlands (VSH), define major clusters of detrital zircons interpreted as coming from (1) 700 to 460 Ma mafic granitoids and alkaline rock, epsilon-Hf 9 to -28, signifying derivation 2.5 to 1.3 Ga from fertile and recycled crust, and (2) 1200-900 Ma mafic granitoids and alkaline rock, epsilon-Hf 11 to -28, signifying derivation 1.8 to 1.3 Ga from fertile and recycled crust. Minor clusters extend to 3350 Ma. Similar detrital zircons in Permian-Triassic, Ordovician, Cambrian, and Neoproterozoic sandstones located along the PaleoPacific margin of East Antarctica and southeast Australia further downslope from central Antarctica reflect the upslope GSM-VSH nucleus of the central Antarctic provenance as a complex of 1200-900 Ma (Grenville) mafic granitoids and alkaline rocks and older rocks embedded in 700-460 Ma (Pan-Gondwanaland) fold belts. The wider central Antarctic provenance (CAP) is tentatively divided into a central sector with negative ?Hf in its 1200-900 Ma rocks bounded on either side by positive epsilon-Hf.The high ground of the GSM-VSH in the Permian and later to the present day is attributed to crustal shortening by far-field stress during the 320 Ma mid-Carboniferous collision of Gondwanaland and Laurussia. Earlier uplifts in the ~500 Ma Cambrian possibly followed the 700-500 Ma assembly of Gondwanaland, and in the Neoproterozoic the 1000-900 Ma collisional events in the Eastern Ghats-Rayner Province at the end of the 1300-1000 Ma assembly of Rodinia.

Supplement to: Veevers, John J; Saeed, Ayesha; O'Brien, Philip E (2008): Provenance of the Gamburtsev Subglacial Mountains from U-Pb and Hf analysis of detrital zircons in Cretaceous to Quaternary sediments in Prydz Bay and beneath the Amery Ice Shelf. Sedimentary Geology, 211(1-2), 12-32

Identifier
DOI https://doi.org/10.1594/PANGAEA.767504
Related Identifier IsSupplementTo https://doi.org/10.1016/j.sedgeo.2008.08.003
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.767504
Provenance
Creator Veevers, John J; Saeed, Ayesha; O'Brien, Philip E ORCID logo
Publisher PANGAEA
Publication Year 2008
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 32 datasets
Discipline Earth System Research
Spatial Coverage (70.290W, -69.900S, 76.382E, -66.400N); Prydz Bay
Temporal Coverage Begin 1988-01-27T12:00:00Z
Temporal Coverage End 2000-02-28T08:25:00Z