georefid:2006-069412SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2006-069412<gco:CharacterString>Sr and Nd analyses of upper Eocene spherules and their implications for target rocks</gco:CharacterString>2006-01-01publicationgeorefid:2006-069412Liu, ShaobinUniversity of Delaware, Department of Geology, Newark, DE, United StatesauthorPapanastassiou, D. A.California Institute of Technology, United StatesauthorNgo, H. H.authorGlass, B. P.authorMeteoritical Society, Fayetteville, AR, United StatespublisherdocumentHardcopyMeteoritics & Planetary Science41 (5)705-714Upper Eocene impact ejecta has been discovered all over the world. The number of upper Eocene impact layers and the geographic distribution of each layer, based on major chemical composition and biostratigraphic data, are not agreed upon. We have performed four Sr-Nd isotopic analyses of clinopyroxene-bearing spherules (cpx spherules) and three Sr-Nd analyses of microtektites from five Deep Sea Drilling Project/Ocean Drilling Program (DSDP/ODP) sites in the South Atlantic and Indian Oceans. Our data support the hypothesis that there is only one cpx spherule layer in upper Eocene sediments. We also find that the microtektites associated with the cpx spherule layer in the South Atlantic and Indian Oceans are not part of the North American tektite strewn field, but belong to the same event that produced the cpx spherules. The microtektites, together with cpx spherules, are more heterogeneous than microtektites/tektites from other strewn fields. No direct link has been established between the microtektites from this study and possible target rock at the Popigai crater.completedIsotope geochemistryalkaline earth metalsAsiaAtlantic OceanCenozoicchain silicateschemical compositionclinopyroxeneCommonwealth of Independent StatesDeep Sea Drilling ProjectDSDP Site 216ejectaenergy dispersive X-ray dataEoceneimpactsIndian Oceanisotope ratiosisotopesLeg 113Leg 115Leg 177Leg 22major elementsmass spectrametalsmicrotektitesNd-144/Nd-143neodymiumNorth American tektitesOcean Drilling ProgramODP Site 1090ODP Site 689ODP Site 709PaleogenePopigay Structurepyroxene grouprare earthsRussian FederationsilicatesSouth AtlanticspectraspherulesSr-87/Sr-86stable isotopesstrewn fieldsstrontiumtarget rockstektitesTertiaryupper Eoceneurn:org.iodp:exp:113urnlargerWorkCitationcampaignurn:org.iodp:exp:115urnlargerWorkCitationcampaignurn:org.iodp:exp:177urnlargerWorkCitationcampaignurn:org.iodp:exp:22urnlargerWorkCitationcampaignurn:org.iodp:exp:22:site:216urnlargerWorkCitationstudyurn:org.iodp:exp:22urnlargerWorkCitationcampaignurn:org.iodp:exp:177:site:1090urnlargerWorkCitationstudyurn:org.iodp:exp:177urnlargerWorkCitationcampaignurn:org.iodp:exp:113:site:689urnlargerWorkCitationstudyurn:org.iodp:exp:113urnlargerWorkCitationcampaignurn:org.iodp:exp:115:site:709urnlargerWorkCitationstudyurn:org.iodp:exp:115urnlargerWorkCitationcampaignEnglishgeoscientificInformation3.055990.1229-64.31011.2744