Radiocarbon dating of alkenones from marine sediments

As a result of the growing use of multiple geochemical proxies to reconstruct ocean and climate changes in the past, there is an increasing need to establish temporal relationships between proxies derived from the same marine sediment record and ideally from the same core sections.Coupled proxy records of surface ocean properties, such as those based on lipid biomarkers (e.g.April 2014 Senior Scientist Department of Geology & Geophysics Woods Hole Oceanographic Institution Woods Hole, Massachusetts 02543 EMail: [email protected]: 5 Fax: 508 457-2183 B. Research Assistant, Graduate School of Oceanography, URI 1974-1979. Research Associate, Graduate School of Oceanography, URI, 1979-1980. 1984 (Jul) Cruise 19, Leg 4, northwest Pacific and Bering Sea; coring, hydro stations, dredging, sediment trap deployments. 1992 (Jun-Aug) JOIDES Resolution ODP Leg 145, North Pacific Transect. Late Cenozoic planktonic foraminiferal biostratigraphy and paleoceanography of the Panama Basin, , v.

The steps involved, which include silica gel column chromatography, urea adduction, and silver nitrate-silica gel column chromatography, exploit various structural attributes of the alkenones.

At least for certain taxa, our analysis provides evidence of their paleoenvironmental selection over the last glacial-interglacial cycle.

In marine sediment, energy-yielding electron acceptors for microbial respiration are sequentially depleted based on the amount of energy they provide, which is linked to the oxidation of organic matter.

Selection of microorganisms in marine sediment is shaped by energy-yielding electron acceptors for respiration that are depleted in vertical succession.

However, some taxa have been reported to reflect past depositional conditions suggesting they have experienced weak selection after burial.

Radiocarbon dating of alkenones from marine sediments