noaa-ocean-2587 Late Paleocene Osmium Isotope Data Ravizza, G.; Norris, R.N.; Blusztajn, J.; Aubry, M-P. Late Paleocene Osmium Isotope Data 2001-01-01 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/2587 Investigator G. Ravizza Investigator R.N. Norris Investigator J. Blusztajn Investigator M-P. Aubry earth science paleoclimate paleoceanography 187Os/188Os,sediment,null,dimensionless,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography 187Re/188Os,sediment,null,dimensionless,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography delta 13C,carbonate,null,per mil PDB,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography rhenium,sediment,null,parts per trillion,null,paleoceanography,null,inductively-coupled plasma mass spectrometry,N,null earth science paleoclimate paleoceanography delta 18O,carbonate,null,per mil PDB,null,paleoceanography,null,null,N,null earth science paleoclimate paleoceanography osmium,sediment,null,parts per trillion,null,paleoceanography,null,inductively-coupled plasma mass spectrometry,N,null earth science paleoclimate paleoceanography depth,null,null,centimeter,null,paleoceanography,null,null,N,null earth science paleoclimate paleocean geochemistry earth science paleoclimate paleocean oxygen isotopes earth science paleoclimate paleocean carbon isotopes geoscientificInformation cal yr BP cal yr BP Complete -10.22 49.088 -13.098 93.9 -5601 -2515 Ocean Indian Ocean DSDP 213>LATITUDE -10.22>LONGITUDE 93.9 Ocean Atlantic Ocean North Atlantic Ocean DSDP 549>LATITUDE 49.088>LONGITUDE -13.098 None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Ravizza, G., R.N. Norris, J. Blusztajn, and M-P. Aubry. 2001. An osmium isotope excursion associated with the late Paleocene thermal maximum: Evidence of intensified chemical weathering. Paleoceanography 16(2):155-163.

In the latest Paleocene an abrupt shift to more negative delta13C values has been documented at numerous marine and terrestrial sites [Bralower et al., 1997; Cramer et al., 1999; Kaiho et al., 1996; Kennett and Stott, 1991; Koch et al., 1992; Stott et al., 1996; Thomas and Shackleton, 1996; Zachos et al., 1993]. This carbon isotope event (CIE) is coincident with oxygen isotope data that indicate warming of surface waters at high latitudes of nearly 4°--6 °C [Kennett and Stott, 1991] and more moderate warming in the subtropics [Thomas et al., 1999]. Here we report 187Os/188Os isotope records from the North Atlantic and Indian Oceans which demonstrate a >10% increase in the 187Os/188Os ratio of seawater coincident with the late Paleocene CIE. This excursion to higher 187Os/188Os ratios is consistent with a global increase in weathering rates. The inference of increased chemical weathering during this interval of unusual warmth is significant because it provides empirical evidence supporting the operation of a feedback between chemical weathering rates and warm global climate, which acts to stabilize Earth's climate [Walker et al., 1981]. Estimates of the duration of late Paleocene CIE [Bains et al., 1999; Bralower et al., 1997; Norris and Röhl, 1999; Röhl et al., 2000] in conjunction with the Os isotope data imply that intensified chemical weathering in response to warm, humid climates can occur on timescales of 104--105 years. This interpretation requires that the late Palcocene thermal maximum Os isotope excursion be produced mainly by increased Os flux to the ocean rather than a transient excursion to higher 187Os/188Os ratios in river runoff. Although we argue that the former is more likelythan the latter, we cannot rule out significant changes in the 187Os/188Os ratio of rivers.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/dsdp213-tab.txt GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/ravizza2001 GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/dsdp549-tab.txt USA/NOAA DIF Version 9.8.4 2019-01-29 2019-01-29