A. Mackensen, G. Schmiedl
Jul 3, 2019
Citations
3
Influential Citations
64
Citations
Journal
Earth-Science Reviews
Abstract
Abstract Carbon is one of the key elements in organisms and non-living compounds on Earth. Carbon dioxide and methane are important greenhouse gases in the atmosphere, dissolved inorganic (DIC) and organic carbon (DOC) determine water biogeochemistry, and carbonates are major constituents of marine sediments. Stable carbon isotope ratios ( 13 C/ 12 C), expressed as δ 13 C values, are widely used in Modern Earth sciences. δ 13 C CO2 values of atmospheric carbon dioxide reflect global climate evolution and change. Marine δ 13 C DIC is used as water-mass tracer and helps quantifying the anthropogenic CO 2 uptake of the ocean. The δ 13 C values of fossil planktic and benthic carbonates indicate changes in circulation pattern and deep-water ventilation of ancient oceans, as well as paleoproductivity at the sea surface and methane release at the sea floor. The δ 13 C OM values of sedimentary organic matter (OM) and compound-specific δ 13 C values of molecular organic biomarkers indicate whether the organic carbon is of marine or terrestrial provenience. Secular δ 13 C variations and excursions in carbonates are important stratigraphic marker and tie points. Here we review the application of stable carbon isotope ratios in ocean water and biogenic carbonates as proxies in paleoceanography, including the atmospheric and sedimentary reservoirs oceanic carbon is in exchange with. Due to the wide use of δ 13 C values in Earth sciences, this overview necessarily does not claim to be complete; rather we focus on field-based stable carbon isotope research and its significance in paleoceanography. This may assist in evaluating general circulation model results and foster development of new innovative proxies.