Distinct iron isotopic signatures and supply from marine sediment dissolution

William B. Homoky; Seth G. John; Tim M. Conway; Rachel A. Mills

doi:10.1038/ncomms3143

journal article Open Access Jul 19, 2013

Distinct iron isotopic signatures and supply from marine sediment dissolution

William B. Homoky

Seth G. John

Tim M. Conway

Rachel A. Mills

Nature Communications Vol. 4 No. 1 · Springer Science and Business Media LLC

View at Publisher Save 10.1038/ncomms3143

Abstract

AbstractOceanic iron inputs must be traced and quantified to learn how they affect primary productivity and climate. Chemical reduction of iron in continental margin sediments provides a substantial dissolved flux to the oceans, which is isotopically lighter than the crust, and so may be distinguished in seawater from other sources, such as wind-blown dust. However, heavy iron isotopes measured in seawater have recently led to the proposition of another source of dissolved iron from ‘non-reductive’ dissolution of continental margins. Here we present the first pore water iron isotope data from a passive-tectonic and semi-arid ocean margin (South Africa), which reveals a smaller and isotopically heavier flux of dissolved iron to seawater than active-tectonic and dysoxic continental margins. These data provide in situ evidence of non-reductive iron dissolution from a continental margin, and further show that geological and hydro-climatic factors may affect the amount and isotopic composition of iron entering the ocean.

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Published: Jul 19, 2013
Vol/Issue: 4(1)
License: View

Authors

Inst. of Geochemistry and Petrology; Dept. of Earth Sciences; ETH Zürich; Switzerland

R

Rachel A. Mills

Cite This Article

William B. Homoky, Seth G. John, Tim M. Conway, et al. (2013). Distinct iron isotopic signatures and supply from marine sediment dissolution. Nature Communications, 4(1). https://doi.org/10.1038/ncomms3143

Distinct iron isotopic signatures and supply from marine sediment dissolution

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