Sediment record from the western Arctic Ocean with an improved Late Quaternary age resolution: HOTRAX core HLY0503-8JPC, Mendeleev RidgeShow others and affiliations
Responsible organisation
2009 (English)In: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 68, no 1-2, p. 18-29Article in journal (Refereed) Published
Abstract [en]
Sediment core HLY0503-8JPC raised by the HOTRAX'05 expedition from the Mendeleev Ridge was analyzed for multiple lithological, paleontological, and stable-isotopic proxies to reconstruct paleoceanographic conditions in the western Arctic Ocean during the Late Quaternary. The core, extensively sampled in the upper 5 m, reveals pronounced changes in sedimentary environments during the ca. 250 kyr interval encompassing Marine Isotopic Stages (MIS) 1 to 7. An estimated average resolution of 500 yr/sample, at least for the last glacial cycle including the last interglacial, provides more detail than seen in other sedimentary records from the western Arctic Ocean. The age control is provided by 14C and amino acid racemization measurements on planktonic foraminifers and correlations with the stratigraphy developed for the central Lomonosov Ridge and with glacial events at the Eurasian Arctic margin. Cyclic variations in lithology combined with foraminiferal abundance and stable-isotopic composition indicate profound changes in hydrographic and depositional environments between interglacial-type and glacial-type periods apparently reflecting a combination of 100-kyr and precessional time scales. This periodicity is complicated by abrupt iceberg- and/or meltwater-discharge events with variable (Laurentide vs. Eurasian) provenance. The proxy record from the interval identified as the last interglacial (MIS 5e), which may aid in understanding the future state of the Arctic Ocean, indicates low ice conditions and possibly enhanced stratification of the water column.
Place, publisher, year, edition, pages
2009. Vol. 68, no 1-2, p. 18-29
Keywords [en]
Arctic Ocean, Mendeleev Ridge, sediment stratigraphy, Late Quaternary, glaciations, last interglacial, HOTRAX 2005, SWEDARCTIC 2005
Research subject
SWEDARCTIC 2005, Beringia 2005
Identifiers
URN: urn:nbn:se:polar:diva-21DOI: 10.1016/j.gloplacha.2009.03.026OAI: oai:DiVA.org:polar-21DiVA, id: diva2:568151
Note
Source: Polardok by Swedish Polar Research Secretariat
Special Issue "The 2005 HOTRAX Expedition to the Arctic Ocean"
2012-11-152012-11-152017-12-07