(Table 1) Age markers and errors for the last 1215 ka in IODP Exp302


Despite its importance in the global climate system, age-calibrated marine geologic records reflecting the evolution of glacial cycles through the Pleistocene are largely absent from the central Arctic Ocean. This is especially true for sediments older than 200 ka. Three sites cored during the Integrated Ocean Drilling Program's Expedition 302, the Arctic Coring Expedition (ACEX), provide a 27 m continuous sedimentary section from the Lomonosov Ridge in the central Arctic Ocean. Two key biostratigraphic datums and constraints from the magnetic inclination data are used to anchor the chronology of these sediments back to the base of the Cobb Mountain subchron (1215 ka). Beyond 1215 ka, two best fitting geomagnetic models are used to investigate the nature of cyclostratigraphic change. Within this chronology we show that bulk and mineral magnetic properties of the sediments vary on predicted Milankovitch frequencies. These cyclic variations record ''glacial'' and ''interglacial'' modes of sediment deposition on the Lomonosov Ridge as evident in studies of ice-rafted debris and stable isotopic and faunal assemblages for the last two glacial cycles and were used to tune the age model. Potential errors, which largely arise from uncertainties in the nature of downhole paleomagnetic variability, and the choice of a tuning target are handled by defining an error envelope that is based on the best fitting cyclostratigraphic and geomagnetic solutions.

Depths are given in revised meters composite depth (rmcd) with the best estimate for the age provided in the second column. The type of marker that was used to derive the age estimate is given in the third column; SC is stratigraphic correlation to cores 96/12-1PC and PS2185-6; NGS is Norwegian-Greenland Sea. Minimum and maximum age estimates are provided with both the method of determination and the source of the error estimate where applicable.

DOI https://doi.org/10.1594/PANGAEA.733880
Related Identifier IsPartOf https://doi.org/10.1594/PANGAEA.832427
Related Identifier References https://doi.org/10.1029/2007PA001551
Related Identifier IsDocumentedBy https://doi.org/10.1029/2007PA001484
Related Identifier IsDocumentedBy https://doi.org/10.1016/j.pepi.2005.10.009
Related Identifier IsDocumentedBy https://doi.org/10.1016/0033-5894(87)90046-9
Related Identifier IsDocumentedBy https://doi.org/10.1007/s005310050250
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.733880
Creator O'Regan, Matthew; King, John W; Backman, Jan; Jakobsson, Martin ORCID logo; Pälike, Heiko ORCID logo; Moran, Kathryn; Heil, Chip; Sakamoto, Tatsuhiko; Cronin, Thomas M; Jordan, Richard William ORCID logo
Publisher PANGAEA
Publication Year 2010
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Resource Type Dataset
Format text/tab-separated-values
Size 124 data points
Discipline Earth System Research
Spatial Coverage (137.650 LON, 87.890 LAT)