Global Ocean Neodymium Isotope Data during the Campanian-Maastrichtian Haynes, S.J.; MacLeod, K.G.; Vande Guchte, A.; Rostami, M.A.; Poulsen, C.J.; Martin, E.E. Haynes, S.J. MacLeod, K.G. Vande Guchte, A. Rostami, M.A. Poulsen, C.J. Martin, E.E. earth science/paleoclimate/paleocean (ODP 1276A>LATITUDE 45.40533>LONGITUDE -44.785827) (DSDP 289>LATITUDE -.499>LONGITUDE 158.512) (DSDP 358>LATITUDE -37.655>LONGITUDE -35.964) (DSDP 386>LATITUDE 31.187>LONGITUDE -64.249) (ODP 698A>LATITUDE -51.459>LONGITUDE -33.099) (DSDP 357>LATITUDE -30.42>LONGITUDE -35.57) (TZ_2014>LATITUDE -8.949>LONGITUDE 39.333) (DSDP 317A>LATITUDE -11.002>LONGITUDE -162.263) (DSDP 530A>LATITUDE -19.188>LONGITUDE 9.386) (ODP 1001A>LATITUDE 15.757>LONGITUDE -74.911) (ODP 1186A>LATITUDE -.68>LONGITUDE 159.844) (DSDP 516>LATITUDE -30.2765>LONGITUDE -35.285) (ODP 1267>LATITUDE -28.098>LONGITUDE 1.711) (DSDP 463>LATITUDE 21.35>LONGITUDE 174.668) (ODP 700B>LATITUDE -51.533>LONGITUDE -30.278) (DSDP 387>LATITUDE 32.3167>LONGITUDE -67.6667) (DSDP 550B>LATITUDE 48.516>LONGITUDE -13.438667) (DSDP 356>LATITUDE -28.287>LONGITUDE -41.088) (DSDP 361>LATITUDE -35.066>LONGITUDE 15.449) (ODP 1262>LATITUDE -27.186>LONGITUDE 1.577) (DSDP 525A>LATITUDE -29.071>LONGITUDE 2.985) (ODP 761B>LATITUDE -16.737>LONGITUDE 115.535) (ODP 807C>LATITUDE 3.606>LONGITUDE 156.625) (Caravaca>LATITUDE 38.076>LONGITUDE -1.878) Models for changing patterns of ocean circulation during the last 10 million years of the Cretaceous (late Campanian–Maastrichtian) have suggested increased downwelling occurred in the Southern Ocean and/or the North Atlantic as well as alternating between northern and southern high-latitude Pacific source regions across the interval. Existing data do not allow simple confirmation or rejection of any of the proposed models, and this uncertainty compromises investigations of the relationship between ocean circulation and climate. Here we use neodymium isotopes (eNd) preserved in fossilized fish debris to examine changes in Pacific circulation by comparing trends from the late Campanian through the Maastrichtian to patterns during a well-documented early Maastrichtian cooling pulse (EMCP). Pacific eNd data have similar values in late Campanian and late Maastrichtian samples but show a small negative eNd excursion that closely correlates with the EMCP. These observations argue against export of southern component waters into the Pacific and, combined with new modeling results of subsurface water mass age, suggest the southwestern Pacific to have been the dominant source region for Pacific intermediate and deep waters throughout the late Campanian–Maastrichtian. We propose that changes in eNd values during the EMCP are related to an increased rate of overturning rather than a shift in the source of Pacific bottom waters. STUDY NOTES: Late Campanian to Maastrictian Nd isotopic data from DSDP Sites289, 217, 356, 357, 358, 361, 386, 387, 463, 516, 525, 530, 550, OPD Sites 698, 700, 761, 807, 1001, 1262, 1267, 1276 and field samples from Caravaca, Spain and southeast Tanzania Provided Keywords: Cretaceous, ocean circulation, Nd isotopes, Pacific, South Atlantic NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Haynes, S.J. Investigator : MacLeod, K.G. Investigator : Vande Guchte, A. Investigator : Rostami, M.A. Investigator : Poulsen, C.J. Investigator : Martin, E.E. 2019-02-11 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/26090 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/haynes2019/haynes2019-nd.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/haynes2019/haynes2019-nd.txt English https://www.ncdc.noaa.gov/paleo/study/26090 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/haynes2019/haynes2019-nd.txt Haynes, S.J., MacLeod, K.G., Vande Guchte, A., Rostami, M.A., Poulsen, C.J., Martin, E.E.2019Constraining sources and relative flow rates of bottom waters in the Late Cretaceous Pacific OceanGeologyin review Haynes, S.J., MacLeod, K.G., Vande Guchte, A., Rostami, M.A., Poulsen, C.J., and Martin, E.E.2019The role of the Rio Grande Rise – Walvis Ridge system in controlling intermediate- and deep-ocean circulation patterns at the end of the Cretaceousin preparation START YEAR: 100000000 cal yr BP * END YEAR: 60000000 cal yr BP -162.263 -51.533 174.668 48.516