Sengupta, Sukanya

[["dc.bibliographiccitation.firstpage","18"],["dc.bibliographiccitation.journal","Chemical Geology"],["dc.bibliographiccitation.lastpage","26"],["dc.bibliographiccitation.volume","495"],["dc.contributor.author","Sengupta, Sukanya"],["dc.contributor.author","Pack, Andreas"],["dc.date.accessioned","2019-07-24T07:14:53Z"],["dc.date.available","2019-07-24T07:14:53Z"],["dc.date.issued","2018"],["dc.description.abstract","The oxygen isotope composition of the Earth's oceans is buffered by high- and low-T exchange with the lithosphere. We present a triple oxygen isotope mass balance model for the Earth's oceans. The model is based on triple oxygen isotope measurements of rocks from various reservoirs including high- and low-T alteration products. The modern ocean water composition can be well-matched if the ratio between continental weathering and high-T seafloor alteration is ~25% higher than previously assumed. The mass balance suggests that putative Precambrian low-δ18O ocean water would fall on a trend with slope λ = 0.51 passing through “modern” ice-free-world seawater. Exemplified application to a published Phanerozoic and Archean chert data suggest precipitation in cool oceans with modern-like δ18O followed by diagenetic alteration with involvement of meteoric water."],["dc.identifier.doi","10.1016/j.chemgeo.2018.07.012"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16296"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/61958"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","0009-2541"],["dc.rights","CC BY-ND 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by-nd/4.0"],["dc.title","Triple oxygen isotope mass balance for the Earth's oceans with application to Archean cherts"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","15702"],["dc.bibliographiccitation.journal","Nature communications"],["dc.bibliographiccitation.lastpage","15702"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Pack, Andreas"],["dc.contributor.author","Höweling, Andres"],["dc.contributor.author","Hezel, Dominik C."],["dc.contributor.author","Stefanak, Maren T."],["dc.contributor.author","Beck, Anne-Katrin"],["dc.contributor.author","Peters, Stefan T. M."],["dc.contributor.author","Sengupta, Sukanya"],["dc.contributor.author","Herwartz, Daniel"],["dc.contributor.author","Folco, Luigi"],["dc.date.accessioned","2019-07-09T11:43:29Z"],["dc.date.available","2019-07-09T11:43:29Z"],["dc.date.issued","2017-06-01"],["dc.description.abstract","Molten I-type cosmic spherules formed by heating, oxidation and melting of extraterrestrial Fe,Ni metal alloys. The entire oxygen in these spherules sources from the atmosphere. Therefore, I-type cosmic spherules are suitable tracers for the isotopic composition of the upper atmosphere at altitudes between 80 and 115 km. Here we present data on I-type cosmic spherules collected in Antarctica. Their composition is compared with the composition of tropospheric O2. Our data suggest that the Earth's atmospheric O2 is isotopically homogenous up to the thermosphere. This makes fossil I-type micrometeorites ideal proxies for ancient atmospheric CO2 levels."],["dc.identifier.doi","10.1038/ncomms15702"],["dc.identifier.pmid","28569769"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14540"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58894"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","2041-1723"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0/"],["dc.subject.ddc","550"],["dc.title","Tracing the oxygen isotope composition of the upper Earth's atmosphere using cosmic spherules"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]