Fine-silt luminescence dating and mineral composition of sediments from the Arctic Ocean, supplement to: Berger, Glenn W (2006): Trans-arctic-ocean tests of fine-silt luminescence sediment dating provide a basis for an additional geochronometer for this region. Quaternary Science Reviews, 25(19-20), 2529-2551

DOI

New geochronometers are needed for sediments of the Arctic Ocean spanning at least the last half million years, largely because oxygen-isotope stratigraphy is relatively ineffective in this ocean, and because other dating techniques require significant assumptions about sedimentation rates. Multi-aliquot luminescence sediment-dating procedures were applied to polymineral, fine-silt samples from 9 core-top and 37 deeper samples from 20 cores representing 19 sites across the Arctic Ocean. Most samples have independent age assignments and other known properties (e.g., % coarse fraction, % carbonate, U-Th isotopes). Thick-source alpha-particle counting indicates that for most regions the contribution of measured unsupported 230Th and 231Pa to calculated dose rates is <ca+5–11%. IR-PSL dating of polymineral fine-silt fractions from core-top and near-core-top samples indicates that three sites (mainly from the western Arctic Ocean) have long-bleach inherited ages of only 3–7 kyr, suggesting potential for accurate PSL and TL dating without an inherited correction when older interglacial samples are selected. Samples from a giant gravity core from the western region (Northwind Ridge) yield acceptable long-bleach TL and IR-PSL ages up to 100 kyr. A sample from the eastern region (near Gakkel Ridge) gives a long-bleach age of ca 60 kyr, agreeing with an independent age assignment. Several samples in the 10–40 kyr 14C range from other sites produce large long-bleach age overestimates, indicating the variable effects of ice-rafting and other depositional and bottom-currentreworking (re-suspension) processes during glacial stages. Short-bleach dating tests provide IR-PSL age estimates for core tops that appear to penetrate the 'reworking veil' of inherited ages, and not only suggest a procedure to greatly reduce long-bleach inherited ages but also have implications for the 14C reservoir correction. This study identifies the most promising regions for future luminescence dating, and suggests that for several regions of the Arctic Ocean, interglacial-stage (foram-'rich') sediments from ridge tops are preferred for the fine-grain luminescence dating methods.

Identifier
DOI https://doi.org/10.1594/PANGAEA.669644
Related Identifier https://doi.org/10.1016/j.quascirev.2005.07.024
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.669644
Provenance
Creator Berger, Glenn W
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2007
Rights Creative Commons Attribution 3.0 Unported
OpenAccess true
Representation
Language English
Resource Type Supplementary Collection of Datasets
Format application/zip
Size 18 datasets
Discipline Earth System Research
Spatial Coverage (-2.557W, 71.070S, 9.617E, 88.870N); Arctic Ocean; Svalbard; Antarctic Ocean; Gakkel Ridge, Arctic Ocean; Amundsen Basin; Lomonosov Ridge, Arctic Ocean; Morris Jesup Rise
Temporal Coverage Begin 1987-07-27T00:00:00Z
Temporal Coverage End 1991-09-22T00:00:00Z