skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Radiocarbon ages of sedimentary lipids as tracers of organic carbon input to marine sediments

Abstract

A novel analytical approach, Preparative Capillary Gas Chromatography (PCGC), has been used to isolate sufficient quantities of individual hydrocarbon lipids from two marine surface sediments (Black Sea, Arabian Sea) for radiocarbon dating by Accelerator Mass Spectrometry (AMS). {Delta}{sup 14}C values for bulk sedimentary organic carbon (OC) from the Black and Arabian Sea samples are -105 and -112{per_thousand} respectively. In the Black Sea, extended [higher plant] n-alkanes (n-C{sub 29}, n-C{sub 31}) are significantly enriched relative to bulk OC (ave -80{per_thousand}), indicating input of {open_quotes}fresh{close_quotes} terrestrial organic matter, while shorter chain homologues (n-C{sub 23}, n-C{sub 25}) exhibit depleted (ca. -160{per_thousand}) values, in keeping with the total hydrocarbon fraction (-150{per_thousand}). Arabian Sea hydrocarbons exhibit a much wider range of {Delta}{sup 14}C values (from -38 to -780{per_thousand}). Markers for diatoms (highly branched isoprenoid alkenes) show the youngest radiocarbon ages while saturated hydrocarbons display the oldest ages. We interpret these variations in terms of uptake of atmospheric CO{sub 2} and contributions from relic carbon sources. These and related data will be discussed in the context of organic carbon input and preservation in these marine systems.

Authors:
; ;  [1]
  1. Woods Hole Oceanographic Institution, MA (United States); and others
Publication Date:
OSTI Identifier:
370446
Report Number(s):
CONF-960376-
TRN: 96:003805-0498
Resource Type:
Conference
Resource Relation:
Conference: Spring national meeting of the American Chemical Society (ACS), New Orleans, LA (United States), 24-28 Mar 1996; Other Information: PBD: 1996; Related Information: Is Part Of 211th ACS national meeting; PB: 2284 p.
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; LIPIDS; ISOTOPE DATING; ALKANES; ARABIAN SEA; CARBON SOURCES; GAS CHROMATOGRAPHY; ORGANIC MATTER; SEDIMENTS; CARBON 14; CARBON DIOXIDE; BLACK SEA

Citation Formats

Eglinton, T I, Nelson, B, and McNichol, A P. Radiocarbon ages of sedimentary lipids as tracers of organic carbon input to marine sediments. United States: N. p., 1996. Web.
Eglinton, T I, Nelson, B, & McNichol, A P. Radiocarbon ages of sedimentary lipids as tracers of organic carbon input to marine sediments. United States.
Eglinton, T I, Nelson, B, and McNichol, A P. Tue . "Radiocarbon ages of sedimentary lipids as tracers of organic carbon input to marine sediments". United States.
@article{osti_370446,
title = {Radiocarbon ages of sedimentary lipids as tracers of organic carbon input to marine sediments},
author = {Eglinton, T I and Nelson, B and McNichol, A P},
abstractNote = {A novel analytical approach, Preparative Capillary Gas Chromatography (PCGC), has been used to isolate sufficient quantities of individual hydrocarbon lipids from two marine surface sediments (Black Sea, Arabian Sea) for radiocarbon dating by Accelerator Mass Spectrometry (AMS). {Delta}{sup 14}C values for bulk sedimentary organic carbon (OC) from the Black and Arabian Sea samples are -105 and -112{per_thousand} respectively. In the Black Sea, extended [higher plant] n-alkanes (n-C{sub 29}, n-C{sub 31}) are significantly enriched relative to bulk OC (ave -80{per_thousand}), indicating input of {open_quotes}fresh{close_quotes} terrestrial organic matter, while shorter chain homologues (n-C{sub 23}, n-C{sub 25}) exhibit depleted (ca. -160{per_thousand}) values, in keeping with the total hydrocarbon fraction (-150{per_thousand}). Arabian Sea hydrocarbons exhibit a much wider range of {Delta}{sup 14}C values (from -38 to -780{per_thousand}). Markers for diatoms (highly branched isoprenoid alkenes) show the youngest radiocarbon ages while saturated hydrocarbons display the oldest ages. We interpret these variations in terms of uptake of atmospheric CO{sub 2} and contributions from relic carbon sources. These and related data will be discussed in the context of organic carbon input and preservation in these marine systems.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1996},
month = {10}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: