georefid:2008-094417SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=10.1126/science.1154339<gco:CharacterString>Synchronizing rock clocks of Earth history</gco:CharacterString>2008-01-01publicationgeorefid:2008-094417doi:10.1126/science.1154339Kuiper, K. F.Utrecht University, Department of Earth Sciences, Utrecht, NetherlandsauthorDeino, A.Berkeley Geochronology Center, United StatesauthorHilgen, F. J.Vrije Universiteit Amsterdam, NetherlandsauthorKrijgsman, W.authorRenne, P. R.authorWijbrans, J. R.authorAmerican Association for the Advancement of Science, Washington, DC, United StatespublisherdocumentDigitalScience320 (5875)500-504Calibration of the geological time scale is achieved by independent radioisotopic and astronomical dating, but these techniques yield discrepancies of approximately 1.0% or more, limiting our ability to reconstruct Earth history. To overcome this fundamental setback, we compared astronomical and (super 40) Ar/ (super 39) Ar ages of tephras in marine deposits in Morocco to calibrate the age of Fish Canyon sanidine, the most widely used standard in (super 40) Ar/ (super 39) Ar geochronology. This calibration results in a more precise older age of 28.201 + or - 0.046 million years ago (Ma) and reduces the (super 40) Ar/ (super 39) Ar method's absolute uncertainty from approximately 2.5 to 0.25%. In addition, this calibration provides tight constraints for the astronomical tuning of pre-Neogene successions, resulting in a mutually consistent age of approximately 65.95 Ma for the Cretaceous/Tertiary boundary.completedGeochronologyStratigraphyabsolute ageAfricaAr/ArcalibrationCenozoicclimate forcingcorrelationCretaceouscyclesEuropegeochronologyIberian PeninsulaK-T boundarylower PaleoceneMesozoicMoroccoNeogeneNorth AfricaOcean Drilling Programorbital forcingPaleocenepaleoenvironmentPaleogeneprobabilitySouthern EuropeSpainstatistical analysisstratigraphic boundarystratigraphic unitsTertiarytime scalesUpper CretaceousEnglishgeoscientificInformation-13.15004.300027.400043.4500MoroccoSpainapplication/pdfunknownSEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContacthttp://www.sciencemag.org/content/320/5875/500.full.pdfdownload