georefid:2006-077753georefid:2006-077737SEDIS 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.198.109.2005<gco:CharacterString>Sedimentology, petrology, and volcanology of the lower Aptian oceanic anoxic event (OAE1a), Shatsky Rise, north-central Pacific Ocean</gco:CharacterString>2006-01-01publicationgeorefid:2006-077753doi:10.2973/odp.proc.sr.198.109.2005Marsaglia, Kathleen M.California State University, Department of Geological Sciences, Northridge, CA, United StatesauthorTexas A&M University, Ocean Drilling Program, College Station, TX, United StatespublisherdocumentDigitalIn: Bralower, Timothy J., Premoli Silva, Isabella, Malone, Mitchell J., Arthur, Michael A., Averyt, Kristen B., Bown, Paul R., Brassell, Simon C., Channell, James E. T., Clarke, Leon J., Dutton, Andrea, Eleson, Jason W., Frank, Tracy D., Gylesjo, Susanne, Hancock, Haidi J. L., Kano, Harumasa, Leckie, R. Mark, Marsaglia, Kathleen M., McGuire, Jennifer, Moe, K. T., Petrizzo, Maria Rose, Robinson, Stuart A., Roehl, Ursula, Sager, William W., Takeda, Kotaro, Thomas, Deborah, Williams, Trevor, Zachos, James C., Proceedings of the Ocean Drilling Program; scientific results; extreme warmth in the Cretaceous and Paleogene; a depth transect on Shatsky Rise, Central Pacific; covering Leg 198 of the cruises of the drilling vessel JOIDES Resolution; Yokohama, Japan, to Honolulu, Hawaii; Sites 1207-1214; 27 August-23 October 2001198This petrological study of the lower Aptian Oceanic Anoxic Event (OAE1a) focused on the nature of the organic-rich interval as well as the tuffaceous units above and below it. The volcaniclastic debris deposited just prior to the OAE1a is consistent with reactivation of volcanic centers across the Shatsky Rise, concurrent with volcanism on the Ontong Java Plateau. This reactivation may have been responsible for the sub-OAE1a unconformity. Soon after this volcanic pulse, anomalous amounts of organic matter accumulated on the rise, forming a black shale horizon. The complex textures in the organic-rich intervals suggest a history of periodic anoxia, overprinted by bioturbation. Components include pellets, radiolarians, and fish debris. The presence of carbonate-cemented radiolarite under the OAE1a intervals suggests that there has been large-scale remobilization of carbonate in the system, which in turn may explain the absence of calcareous microfossils in the section. The volcanic debris in the overlying tuffaceous interval differs in that it is significantly epiclastic and glauconitic. It was likely derived from an emergent volcanic edifice.completedStratigraphyanaerobic environmentAptianbiogenic structuresbiostratigraphybioturbationblack shaleclastic rocksCretaceousigneous rocksInvertebrataLeg 198lithostratigraphylower AptianLower Cretaceousmarine environmentMesozoicmicrofossilsNorth PacificNorthwest PacificOcean Drilling ProgramPacific Oceanpaleo-oceanographypaleoenvironmentpetrologyProtistaRadiolariaradiolaritesedimentary rockssedimentary structuresShatsky Risesubmarine environmentunconformitiesvolcanic rocksvolcanismWest Pacificurn:org.iodp:exp:198urnlargerWorkCitationcampaignEnglishgeoscientificInformation157.1500162.460031.340037.4800Available 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/198_SR/VOLUME/CHAPTERS/109.PDFdownload