Eastern Indian Ocean ODP762 Eocene Calcareous Nannofossil Data Shamrock, J.L.; Watkins, D.K. Shamrock, J.L. Watkins, D.K. earth science/paleoclimate/paleocean (ODP762>LATITUDE -19.8869>LONGITUDE 112.2539) A relatively complete section of Eocene (~33.9-55.8 Ma) pelagic chalk from offshore northwestern Australia was used to analyze range and abundance data of ~250 Eocene species to test the efficacy of the existing CP (Okada and Bukry 1980) and NP (Martini 1971) biostratigraphic zonation schemes. Changes in nannofossil diversity, abundance, and community structure were monitored through several Eocene paleoenvironmental events, as identified by changes in d13C and d18O data, to examine variations in surface water conditions. Major changes in nannofossil assemblages, as indicated by dominance crossovers, correspond to paleoenvironmental shifts such as the PETM (Paleocene-Eocene thermal maximum) and the EECO (Early Eocene climatic optimum). This research also provides systematic paleontology and range data for one new genus (Hexadelus) and eight new species or variants (Calcidiscus ellipticus, Cruciplacolithus nebulosus, Cruciplacolithus opacus, Cyclicargolithus parvus, Hexadelus archus, Hayella situliformis var. ovata, Markalius latus, Pedinocyclus annulus) and addresses several taxonomic issues in other Eocene species. STUDY NOTES: Raw Eocene calcareous nannofossil abundance data from ODP Leg 122, Site 762, Eastern Indian Ocean. Data are raw nannofossil counts from 184.49-422.00 msbf (Core 3-4-49cm to 29-1-50cm). Assemblage data was collected by first identifying 500 specimens to species level, except members of Pontosphaeraceae and Syracosphaeraceae, which were rare and sporadic through the section. Additionally, two long traverses were examined to identify rare specimens, which were given a value of 1 and added to the total. This data was used to convert all species and genera to percent abundance for further analysis. Detailed site information can be found in Shamrock and Watkins (2012), or from Leg 122 Initial Reports (Haq et al. 1990) and Scientific Results (Rad et al. 1992). The vast majority of original taxonomic references can be found in Perch-Nielsen (1985) and Bown (1998). Samples were supplied by the International Ocean Drilling Program (IODP). NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Shamrock, J.L. Investigator : Watkins, D.K. 2012-02-23 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/12583 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shamrock2012/shamrock2012.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shamrock2012/shamrock2012.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shamrock2012/shamrock2012.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shamrock2012/shamrock2012.xls English https://www.ncdc.noaa.gov/paleo/study/12583 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shamrock2012/shamrock2012.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/shamrock2012/shamrock2012.xls Shamrock, J.L. and D.K. Watkins. 2012. Eocene calcareous nannofossil biostratigraphy and community structure from Exmouth Plateau, Eastern Indian Ocean (ODP Site 762). Stratigraphy, Vol. 9, no. 1. START YEAR: 55000000 cal yr BP * END YEAR: 35000000 cal yr BP 112.2539 -19.8869 112.2539 -19.8869