georefid:2005-055108SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2005-055108<gco:CharacterString>High-resolution chronology of the lower Pleistocene Otadai and Umegase formations of the Kazusa Group, Boso Peninsula, central Japan; chronostratigraphy of the JNOC TR-3 cores based on oxygen isotope, magnetostratigraphy and calcareous nannofossil</gco:CharacterString>2005-01-01publicationgeorefid:2005-055108Tsuji, TakashiJAPEX Research Center, Chiba, JapanauthorMiyata, YuichiroYamaguchi University, JapanauthorOkada, MakotoIbaraki University, JapanauthorMita, IsaoNihon Tennen Gas, JapanauthorNakagawa, HiroshiGeowindow, JapanauthorSato, YuriJapan Overseas Cooperation Volunteers, TanzaniaauthorNakamizu, MasaruJapan Oil, Gas and Metal National Corporation, JapanauthorNippon Chishitsugaku Gakkai, Tokyo, JapanpublisherdocumentHardcopyChishitsugaku Zasshi = Journal of the Geological Society of Japan111 (1)1-20Detailed oxygen isotope stratigraphy using benthic foraminifers (Bolivina robusta, Bulimina aculeata and Melonis pompilioides) from cored hemipelagic mudstones enables the lower Pleistocene Otadai and Umegase Formations of the Kazusa Group in the Boso Peninsula, central Japan, a turbidite sequence with high depositional rate (average depositional rate of hemipelagic mudstone: 0.9 m/k.y.), to be correlated with astronomically tuned pelagic sequences. Remarkable correlation between this isotope curve and those from DSDP Site 607 from the North Atlantic, and ODP Site 677 and Site 849 from the tropical Pacific is well demonstrated magnetostratigraphically based on the Jaramillo normal Subchronozone. Numerical age model can be addressed to each oxygen isotope event in the studied sequence applying the age for correlative event in the deep sea sequence. As a result of this study, the ages of events are determined as follows; 1) the first occurrence of Gephyrocapsa parallela: 1038-1041 ka, 2) the marker tephra layers O7, O11, O12 and O16: 1050-1056 ka, 1067-1070 ka, 1073-1078 ka and 1101-1105 ka, respectively, 3) the base of the Jaramillo normal Subchronozone: 1068-1084 ka, and 4) the boundary between the Otadai and Umegase Formations: 1011-1017 ka. The maximum error of the age determination is about 6 k.y.. Average sedimentary rates of turbidite sandstones, hemipelagic mudstones and total sediments are 1.9 m/k.y., 0.9 m/k.y. and 2.8 m/k.y., respectively.completedQuaternary geologyalgaeAsiaassemblagesbenthic taxabiostratigraphybiozonesBolivinaBolivinitidaeBuliminaBuliminaceacalcareous compositionCenozoicchemostratigraphyChiba PeninsulaCoccolithophoraceaeDeep Sea Drilling Projectdepositional environmentDSDP Site 607Far EastForaminiferageochemistryGephyrocapsaGephyrocapsa parallelahigh-resolution methodsHonshuInvertebrataIPODisotope ratiosisotopesJapanJaramillo SubchronKasamori FormationKazusa GroupKiwada FormationKokumoto FormationKurotaki FormationLeg 111Leg 138Leg 94lower PleistocenemagnetostratigraphyMandano FormationMelonismicrofossilsMiura GroupnannofossilsO-18/O-16Ocean Drilling ProgramODP Site 677ODP Site 849Ohara FormationOtadai FormationoxygenpaleoenvironmentpaleomagnetismPlantaePleistoceneProtistaQuaternaryRotaliinasedimentary rockssedimentationsedimentation ratesShimosa Groupstable isotopesturbiditeUmegase Formationurn:org.iodp:exp:111urnlargerWorkCitationcampaignurn:org.iodp:exp:138urnlargerWorkCitationcampaignurn:org.iodp:exp:94urnlargerWorkCitationcampaignurn:org.iodp:exp:94:site:607urnlargerWorkCitationstudyurn:org.iodp:exp:94urnlargerWorkCitationcampaignurn:org.iodp:exp:111:site:677urnlargerWorkCitationstudyurn:org.iodp:exp:111urnlargerWorkCitationcampaignurn:org.iodp:exp:138:site:849urnlargerWorkCitationstudyurn:org.iodp:exp:138urnlargerWorkCitationcampaignJapanesegeoscientificInformation-110.3111140.12000.105841.0005