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dc.contributor.authorRobinson, Laura F.  Concept link
dc.contributor.authorAdkins, Jess F.  Concept link
dc.contributor.authorFernandez, Diego P.  Concept link
dc.contributor.authorBurnett, Donald S.  Concept link
dc.contributor.authorWang, S.-L.  Concept link
dc.contributor.authorGagnon, Alexander C.  Concept link
dc.contributor.authorKrakauer, Nir  Concept link
dc.date.accessioned2006-06-28T19:12:45Z
dc.date.available2006-06-28T19:12:45Z
dc.date.issued2006-05-24
dc.identifier.citationGeochemistry Geophysics Geosystems 7 (2006): Q05022en
dc.identifier.urihttps://hdl.handle.net/1912/1046
dc.descriptionAuthor Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 7 (2006): Q05022, doi:10.1029/2005GC001138.en
dc.description.abstractIn this study we use microsampling techniques to explore diagenetic processes in carbonates. These processes are important as they can affect the accuracy of U series chronometry. Fission track maps of deep-sea scleractinian corals show a threefold difference between the minimum and maximum [U] in modern corals, which is reduced to a factor of 2 in fossil corals. We use micromilling and MC-ICP-MS to make detailed analyses of the [U] and δ234Uinitial distributions in corals from 218 ka to modern. Within each fossil coral we observe a large range of δ234Uinitial values, with high δ234Uinitial values typically associated with low [U]. A simple model shows that this observation is best explained by preferential movement of alpha-decay produced 234U atoms (alpha-recoil diffusion). Open-system addition of 234U may occur when alpha-recoil diffusion is coupled with a high [U] surface layer, such as organic material. This process can result in large, whole-coral δ234Uinitial elevations with little effect on the final age. The diagenetic pathways that we model are relevant to both shallow-water and deep-sea scleractinian corals since both exhibit primary [U] heterogeneity and may be subject to U addition.en
dc.description.sponsorshipWe gratefully acknowledge The Comer Foundation for Abrupt Climate Change.en
dc.format.extent3227826 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoen_USen
dc.publisherAmerican Geophysical Unionen
dc.relation.urihttps://doi.org/10.1029/2005GC001138
dc.subjectUraniumen
dc.subjectDiagenesisen
dc.subjectCoralen
dc.subjectDatingen
dc.titlePrimary U distribution in scleractinian corals and its implications for U series datingen
dc.typeArticleen
dc.identifier.doi10.1029/2005GC001138


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