georefid:2004-011525georefid: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.186.112.2003<gco:CharacterString>Core-log integration of natural gamma ray intensity to construct a 10-m.y. continuous sedimentary record off Sanriku, western Pacific margin, ODP sites 1150 and 1151</gco:CharacterString>2003-01-01publicationgeorefid:2004-011525doi:10.2973/odp.proc.sr.186.112.2003Sakamoto, TatsuhikoHokkaido University, Department of Earth and Planetary Sciences, Hokkaido, JapanauthorSaito, SaneatsuCarnegie Institution of Washington, United StatesauthorShimada, ChiekoOcean Drilling Program, United StatesauthorYamane, MasayukiUniversity of Tokyo, JapanauthorTexas 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 1999186Detection of climate response to orbital forcing during Cenozoic long-term global cooling is a key to understanding the behavior of Earth's icehouse climate. Sedimentary rhythm, which is a rhythmic or cyclic variation in the sequence of sediments and sedimentary rocks, is useful for quantitative reconstruction of Earth's evolution during geological time. In this study, we attempt to (1) identify sources of natural gamma ray (NGR) emissions of core recovered during Ocean Drilling Program (ODP) Leg 186 by analyses of physical properties, major element concentrations, diatom abundances, and total organic carbon contents, (2) integrate whole-core NGR intensity of recovered core with wireline logging NGR measurements in order to construct a continuous sedimentary sequence, and (3) discuss changes in the NGR signal in the time domain. This attempt gives us preliminary information to discuss climate stability in relation to orbital forcing thorough geologic time. NGR values are obtained mainly by indirectly measuring the amount of terrigenous minerals including potassium and related elements in the sediments. NGR intensity is also affected by high porosity, which in these sediments was related to the amount of diatom valves. NGR signals might be a proxy of the intensity of the East Asian monsoon off Sanriku. A continuous sedimentary record was constructed by integration of the whole-core NGR intensity measured in sediments obtained from the drilled holes with that measured directly in the borehole by wireline logging, then using a stratigraphic age model to convert to a time series covering 1.3-9.7 Ma with a short break at approximately 5 Ma. High sedimentation rate (H) stages were identified in the sequence, related to intervals of low-amplitude precession and eccentricity variations. The transition of the dominant periodicities through the four H stages may correlate to major shifts in the climate system, including the onset of major Northern Hemisphere glaciation, the initial stage of the East Asian monsoon intensification, and the onset of the East Asian monsoon with uplift of the Himalayas and the Tibetan Plateau.completedStratigraphyalgaeAsiabiostratigraphyCenozoicclimate changeclimate forcingcoolingcoresdiatomseccentricityFar Eastgamma-ray methodsgeochemistryglacial environmentglaciomarine environmentHonshuicehouse effectJapanJapan TrenchLeg 186lithostratigraphymarine environmentmarine sedimentsmicrofossilsNeogeneNorth PacificNorthwest PacificOcean Drilling ProgramODP Site 1150ODP Site 1151orbital forcingPacific Oceanpaleo-oceanographypaleoclimatologypaleoenvironmentphysical propertiesPlantaeprecessionQuaternarySanrikusedimentary rockssedimentsstatistical analysisTertiarytime series analysiswell logsWest 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 HTMLapplication/pdfunknownSEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContacthttp://www-odp.tamu.edu/publications/186_SR/VOLUME/CHAPTERS/112.PDFdownload