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dc.contributor.advisorRoger E. Summons.en_US
dc.contributor.authorGiron, Marie Minh-Thuen_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences.en_US
dc.coverage.spatiale-sp--- f-ti--- e-dk---en_US
dc.date.accessioned2014-02-10T17:02:12Z
dc.date.available2014-02-10T17:02:12Z
dc.date.issued2013en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/84912
dc.descriptionThesis (S.M. in Earth and Planetary Sciences)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2013.en_US
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (pages 67-71).en_US
dc.description.abstractRecords of ocean biogeochemistry in marine sediments show shifts across the Cretaceous-Paleogene boundary (K-Pg) that are simultaneous with the extinction event and onset of the boundary clay deposition. However, the timescale of these records is difficult to determine near the boundary because of fluctuating sedimentation rates and the short duration of the event. In this study, we have used extraterrestrial helium-3 as a constant flux proxy for instantaneous mass accumulation rates in four marine sections: Caravaca, Spain; El Kef, Tunisia; and Hojerup and Kulstirenden, Denmark. These sections are characterized by a thick boundary clay layer and, therefore, are more suitable than many other proxies for high-resolutions studies. In order to better understand the extent of the impact-related perturbations in different paleoenvironments, we performed a high-resolution analysis at Caravaca and lower-resolution analyses at the other three sections. We find that Hojerup and Kulstirenden are not suitable for this analysis due to the probable variation in the flux of extraterrestrial helium-3 as a result of lateral changes in sedimentation rate. Our results suggest that carbonate burial, and likely carbonate production, were more severely affected with increasing paleolatitude. However, the unique depositional environments are probably much more important than just paleolatitude alone. We calculate boundary clay durations of Caravaca and El Kef of 6.45 (h 0.86) kyr and 6.28 (± 1.03) kyr, respectively. These results are consistent with other studies and indicate a uniform, global deposition of the boundary clay and a rapid recovery of carbonate burial in the marine ecosystem after the Cretaceous-Paleogene extinction event.en_US
dc.description.statementofresponsibilityby Marie Minh-Thu Giron.en_US
dc.format.extent75 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectEarth, Atmospheric, and Planetary Sciences.en_US
dc.titleEstablishing geochemical constraints on mass accumulation rates across the Cretaceous-Paleogene boundary with extraterrestrial Helium-3en_US
dc.typeThesisen_US
dc.description.degreeS.M.in Earth and Planetary Sciencesen_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences.en_US
dc.identifier.oclc869214089en_US


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