{"refrec":{"BRefID":341696,"RR":"<b>Clarkson, M.O.; Hennekam, R.; Sweere, T.C.; Andersen, M.B.; Reichart, G.-J.; Vance, D.</b> (2021). Carbonate associated uranium isotopes as a novel local redox indicator in oxidatively disturbed reducing sediments. <i>Geochim. Cosmochim. Acta 311</i>: 12-28. <a href=\"https://dx.doi.org/10.1016/j.gca.2021.07.025\" target=\"_blank\">https://dx.doi.org/10.1016/j.gca.2021.07.025</a>","BEntID":338331,"PublicFlag":1,"CheckedFlag":0,"wosflag":1,"vabbflag":1,"RefStringPartII":". <i>Geochim. Cosmochim. Acta 311</i>: 12-28. <a href=\"https://dx.doi.org/10.1016/j.gca.2021.07.025\" target=\"_blank\">https://dx.doi.org/10.1016/j.gca.2021.07.025</a>","DocTypID":8,"DocType":"Journal article","MarineFlag":0,"FreshFlag":0,"BrackishFlag":0,"TerrestrialFlag":0,"Authorstring":"Clarkson, M.O.; Hennekam, R.; Sweere, T.C.; Andersen, M.B.; Reichart, G.-J.; Vance, D.","OrigTitleTranslFlag":0,"Authorstringtrunc":"Clarkson, M.O. <i>et al.</i>","Englishabstract":"The interpretation of local redox indicators in marine sediments relies on    their preservation. By their nature, such biogeochemical tracers are    susceptible to diagenetic alteration, particularly through    post-depositional re-oxidation of the sediment. This can result in the    mobilization and loss of distinctive redox dependant signatures, leading to    the classical problem that the presence of oxygenated conditions cannot be    robustly inferred by the absence of evidence for anoxia. Authigenic uranium    enrichments, and their isotope signatures (δ<sup>238</sup>U), are widely    used to infer bottom-water and pore-water redox conditions but are    susceptible to later oxidative diagenetic disturbance. Here we explore the    preservation of authigenic δ<sup>238</sup>U signatures in sediment samples    from Sapropel S1 at Site 64PE406-E1 in the Eastern Mediterranean Sea (~1760    m water depth), which was originally deposited under reducing conditions    but severely affected by later oxidative diagenesis and the variable loss    of authigenic U(IV) from the upper sapropel. To this end, we compare U    isotope signatures from bulk measurements (δ<sup>238</sup>U<sub>bulk</sub>)    with detrital corrected authigenic U (δ<sup>238</sup>U<sub>auth</sub>) and    carbonate associated U (δ<sup>238</sup>U<sub>CAU</sub>). In contrast to    open ocean carbonates deposited under fully oxic conditions, sapropelic    carbonate leachates yield δ<sup>238</sup>U<sub>CAU</sub> similar to    calculated δ<sup>238</sup>U<sub>auth</sub>, thus recording (predominantly)    redox dependant isotope fractionation. There is no evidence for significant    isotope fractionation resulting from post-depositional oxidative    diagenesis, but associated authigenic U(IV) removal results in larger    relative detrital contributions to δ<sup>238</sup>U<sub>bulk</sub>, and    hence large uncertainties on δ<sup>238</sup>U<sub>auth</sub> estimates. By    contrast, δ<sup>238</sup>U<sub>CAU</sub> successfully avoids detrital    phases, and the uncertainty associated with detrital corrections, providing    a primary record of changes in local redox conditions. Thus, we propose    that δ<sup>238</sup>U<sub>CAU</sub> can be used for accurate    reconstructions of benthic de-oxygenation in sediments with low U    enrichments, including sediments with post-depositional U(IV) loss and less    reducing environments.","AbstractOtherLang":null,"BibLvlCode":"AS","StandardTitle":"Carbonate associated uranium isotopes as a novel local redox indicator in oxidatively disturbed reducing sediments","OrigTitleLangCode":"en","OrigTitleLangCodeExtended":"eng","OrigTitleLangID":15,"DateLastModified":{"date":"2026-05-27 01:31:34.973108","timezone_type":1,"timezone":"+02:00"},"UserAccessRight":null,"UserAccID":null,"AuthorKeywords":"Uranium isotopes; Sapropel; Oxidative diagenesis; Burn-down","OtherDescriptors":null,"Notes":null,"AnaPub":2021,"MonPub":null,"DateUpdate":"2021-08-10","DateCreate":"2021-08-10","SecASFANote":null,"ConfID":null,"PeerRev":1,"VlizCoreFlag":1,"WoScode":"WOS:000693337600002","VABBcode":null,"OpenAcc":1,"DOI":"10.1016/j.gca.2021.07.025"},"refs":null,"anarec":{"AnaID":341696,"PubliDate":2021,"Pagination":"12-28","XtraPublOfAnaID":null,"ISBN":null,"Volume":"311","Issue":null,"BRefMon":null,"BRefMonRR":null,"BRefXtra":null,"BRefXtraRR":null,"SerBRefID":42901,"SerRR":"Geochimica et Cosmochimica Acta. Elsevier: Oxford,New York etc..  ISSN 0016-7037; e-ISSN 1872-9533","StandardTitleSer":"Geochimica et Cosmochimica Acta","ISSN":"0016-7037","AbbrevSer":"Geochim. Cosmochim. Acta","StandardTitleMon":null,"StartPage":12,"Pages":17,"ToPubliDate":null,"BRefBibLvlCode":"S","SerNotes":null},"monrec":null,"serrec":null,"relations":null,"relationsRev":null,"addrec":null,"othpubs":null,"ownerships":null,"authors":[{"AutName":"Clarkson","Firstname":"Matthew","Initials":"M.O.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":338331,"AutID":438531,"OrderNr":1,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Hennekam","Firstname":"Rick","Initials":"R.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":338331,"AutID":258733,"OrderNr":2,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":"OCS","InsFSN":"Koninklijk Nederlands Instituut voor Onderzoek der Zee; Ocean Sciences","ORCID":"0000-0002-8823-4519","PersID":34917,"InsID":13654},{"AutName":"Sweere","Firstname":"Tim","Initials":"T.C.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":338331,"AutID":462357,"OrderNr":3,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Andersen","Firstname":"Morten","Initials":"M.B.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":338331,"AutID":243870,"OrderNr":4,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Reichart","Firstname":"Gert-Jan","Initials":"G.-J.","Affiliation":"OCS","Discriminator":null,"CorporateFlag":0,"BEntID":338331,"AutID":205637,"OrderNr":5,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":"OCS","InsFSN":"Koninklijk Nederlands Instituut voor Onderzoek der Zee; Ocean Sciences","ORCID":"0000-0002-7256-2243","PersID":15347,"InsID":13654},{"AutName":"Vance","Firstname":"Derek","Initials":"D.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":338331,"AutID":85866,"OrderNr":6,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null}],"mapdetails":null,"datasets":null,"monographs":null,"monparts":null,"serparts":null,"BEntOpen":338331,"BEntPrivate":null,"availability":[{"BInstID":365019,"LibID":2779,"BRefID":341696,"EmbargoDate":null,"FullEmbargoDate":null,"PhysMedID":16,"hasOCRd":1,"ShelfLocCode":"365019","RFID":null,"PaidValue":null,"Medium":"Server","Description":null,"Acronym":null,"Library":"NIOZ","DutchTerm":null,"URL":null,"ClassifID":260,"Classification":"NIOZ Open Repository","ReqLink":null,"ClassifTypID":1,"URLLocation":"https://www.vliz.be/imisdocs/publications/","SubDir":1,"InternalReq":null,"LoggedInReq":null,"Disclaimer":"Disclaimer_NIOZ","DutchDisclaimer":null,"FileFormat":".pdf","FileDescr":"pdf","InsPub":1,"InsID":397,"FileFormID":6,"LendableFlag":null,"PublicFlag":1,"orderLib":"NIOZ","Notes":null,"AccConID":null,"AccessConstraint":null,"LicURL":null}],"litstyles":null,"thespers":null,"arch2discl":805,"SERpubls":[{"PublName":"Elsevier","City":"Oxford,New York etc."}],"MONpubls":null,"pictures":[],"thestermsPath":null,"thestermsASFA":null,"taxtermsASFA":null,"geotermsASFA":null,"collections":null,"conf":null,"proj":null,"Physdatasets":null,"spcols":{"805":{"SpName":"Koninklijk Nederlands Instituut voor Onderzoek der Zee","SpColID":805,"ParSpColID":null,"TopParID":null,"ShortName":"NIOZ","URLLocation":"https://www.vliz.be/imis/nioz/imis.php?refid=","LibID":2779,"OpenRepoFlag":1,"SpTypID":1,"TopParIDNotWebsite":null,"SpColPath":"NIOZ"}},"doi":null,"publs":null,"serparttypes":null,"monauthors":null,"MParts":null,"SParts":null,"hLibs":null,"langs":[{"BEntID":338331,"AbstractFlag":0,"LangID":15,"LangCode":"en","Lang":"English","DutchTerm":"Engels","LangCodeExtended":"eng"},{"BEntID":338331,"AbstractFlag":1,"LangID":15,"LangCode":"en","Lang":"English","DutchTerm":"Engels","LangCodeExtended":"eng"}],"urls":[{"URL":"https://dx.doi.org/10.1016/j.gca.2021.07.025","externalID":"10.1016/j.gca.2021.07.025","URLTypeCode":"DOI","URLID":96118,"URLTypID":13,"URLType":"DOI","URLPrefix":"http://dx.doi.org/"}],"thesterms":null,"taxterms":null,"geoterms":null,"othterms":null,"asfacodes":null,"asfa2codes":null,"thestermsFRIS":null,"taxtermsFRIS":null,"geotermsFRIS":null,"othtermsFRIS":null,"resmessage":"","complete":1,"sessions":{"newSesName":"daan.van.loon@nioz.nl","newSesDate":{"date":"2021-08-10 09:41:05.047000","timezone_type":3,"timezone":"Europe/Brussels"},"updSesName":"daan.van.loon@nioz.nl","updSesDate":{"date":"2021-08-10 09:41:05.047000","timezone_type":3,"timezone":"Europe/Brussels"}}}