georefid:2004-011519georefid:2004-011510SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=10.2973/odp.proc.sr.186.107.2003<gco:CharacterString>Tephrochronological and tephrostratigraphical potential of Pliocene-Pleistocene volcaniclastic deposits in the Japan Forearc, ODP Leg 186</gco:CharacterString>2003-01-01publicationgeorefid:2004-011519doi:10.2973/odp.proc.sr.186.107.2003Hunt, J. B.University of Gloucestershire, Centre for Environmental Change and Quaternary Research, Cheltenham, United KingdomauthorNajman, Yanina M. R.Carnegie Institution of Washington, United StatesauthorTexas A&M University, Ocean Drilling Program, College Station, TX, United StatespublisherdocumentDigitalIn: Suyehiro, Kiyoshi, Sacks, I. Selwyn, Acton, Gary D., Acierno, Michael J., Araki, Eiichiro, Ask, Maria V. S., Ikeda, Akihiro, Kanamatsu, Toshiya, Kim, Gil Young, Li, Jingfen, Linde, Alan T., McWhorter, Paul N., Mora, German, Najman, Yanina M. R., Niitsuma, Nobuaki, Pandit, Benoy K., Roller, Sybille, Saito, Saneatsu, Sakamoto, Tatsuhiko, Shinohara, Masanao, Sun, Yue-Feng, Proceedings of the Ocean Drilling Program, scientific results, Western Pacific geophysical observatories; covering Leg 186 of the cruises of drilling vessel JOIDES Resolution; Yokohama, Japan, to Yokohama, Japan; sites 1150 and 1151, 14 June-14 August 1999186Major element geochemical composition was established for 59 tephra horizons from Ocean Drilling Program Sites 1150 and 1151, located in the Japan forearc. These data, encompassing typically between 15 and 30 individual shard analyses per tephra horizon, were used to investigate the degree to which sediment reworking, postdepositional geochemical alteration, and geochemical uniqueness of individual eruptives facilitate or impede the potential for establishing a tephrostratigraphical framework for the Japan Trench, as well as usage of the tephra record to document arc evolution. Evidence was found that hydration (termed phase 1 alteration) of glass shards increases with age in the Pliocene-Pleistocene, but there is no indication that element leaching (phase 2 alteration) has occurred. Post- or syn-depositional differences in preservational style are shown to have no significant bearing on tephrogeochemical homogeneity and suitability for tephrostratigraphical analysis. Overall, therefore, the volcaniclastic record is suitable for investigating medium- to long-term changes in arc geochemistry and, provided consideration is given to the potential for nonunique geochemical signatures, is suitable for erecting tephrochronological frameworks. A limited number of Pleistocene tephra correlations are suggested in furtherance of this framework goal.completedStratigraphyGeochemistry of rocks, soils, and sedimentsbasinsCenozoicchemical compositioncoreselectron probe datafore-arc basinsgeochemistryJapan TrenchLeg 186lithostratigraphymajor elementsmarine environmentmarine sedimentsNeogeneNorth PacificNorthwest PacificOcean Drilling ProgramODP Site 1150ODP Site 1151Pacific OceanPleistocenePlioceneQuaternarysedimentstephrochronologyTertiaryvolcaniclasticsWest Pacificurn:org.iodp:exp:186urnlargerWorkCitationcampaignurn:org.iodp:exp:186:site:1150urnlargerWorkCitationstudyurn:org.iodp:exp:186urnlargerWorkCitationcampaignurn:org.iodp:exp:186:site:1151urnlargerWorkCitationstudyurn:org.iodp:exp:186urnlargerWorkCitationcampaignEnglishgeoscientificInformation143.2000143.200038.450039.1100Available only on CD-ROM in PDF format and on the Web in PDF or HTML; includes appendicesapplication/pdfunknownSEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContacthttp://www-odp.tamu.edu/publications/186_SR/VOLUME/CHAPTERS/107.PDFdownload