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dc.contributor.advisorDodd, Justin P.en_US
dc.contributor.authorWiedenheft, Wilsonen_US
dc.date.accessioned2017-08-02T21:16:20Z
dc.date.available2017-08-02T21:16:20Z
dc.date.issued2014
dc.identifier.urihttp://commons.lib.niu.edu/handle/10843/17771
dc.descriptionAdvisors: Justin P. Dodd.en_US
dc.descriptionCommittee members: Neil Blackstone; Reed Scherer.en_US
dc.description.abstractOxygen isotope values of biogenic silica are increasingly used as proxies of paleoenvironmental conditions. A number of studies have demonstrated a strong relationship between the diatom silica and the temperature/oxygen isotope value of the formation water; however, some studies have indicated that early diagenesis of biogenic silica may alter the oxygen isotope values by several permil. Quantification of the maturation process has proven difficult since the mechanisms that drive post-mortem changes in the silica oxygen isotope values have not been well characterized. New silica maturation data from marine diatom, Stephanopyxis turris, cultured in a controlled laboratory experiment, demonstrate a rapid post-mortem decline in silica reactivity. A decrease in relative abundance of surface silanol groups coincides with a decrease in the surface charge density of freshly harvested frustules. These experiments demonstrate that rapid post-mortem alteration of biogenic silica provides a possible mechanism for alteration of oxygen isotope values in biogenic silica.en_US
dc.format.extent71 pagesen_US
dc.language.isoengen_US
dc.publisherNorthern Illinois Universityen_US
dc.rightsNIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.en_US
dc.subject.lcshOxygen--Isotopesen_US
dc.subject.lcshSilicaen_US
dc.subject.lcshIsotope geologyen_US
dc.subject.lcshGeologyen_US
dc.subject.lcshGeochemistryen_US
dc.titleImpact of post-mortem alternation on oxygen isotope values of diatom silicaen_US
dc.typeTexten_US
dc.contributor.departmentDepartment of Geology and Environmental Geosciencesen_US
dc.description.degreeM.S. (Master of Science)en_US


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