Proc. IODP, 318, Data report: foraminiferal stable isotope and percent calcium carbonate analysis from IODP Expedition 318 Hole U1361A

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Abstract Introduction Methods Sample preparation and foraminifer identification Stable isotopes Age model Calcium carbonate weight percent and methane concentration Results Calcium carbonate content Methane concentration Hole U1361A foraminiferal data Stable isotopes Acknowledgments References Figures Figure F1. Location map. Figure F2. Age model. Figure F3. Methane concentrations. Figure F4. Light microscope images. Figure F5. Stable isotope time series. Tables Table T1. CaCO₃. Table T2. Methane concentrations. Table T3. Benthic foraminifers. Table T4. Oxygen isotope data. Table T5. Carbon isotope data. Table T6. Sample request database. PDF file			Previous \| Next doi:10.2204/iodp.proc.318.202.2016 Data report: foraminiferal stable isotope and percent calcium carbonate analysis from IODP Expedition 318 Hole U1361A¹ Matthew DeCesare² and Stephen Pekar³ Abstract A newly recognized carbonate preservation event (CPE) dated between 11 and 12 Ma was identified in Hole U1361A during Integrated Ocean Drilling Program Expedition 318 in the Southern Ocean based on CaCO₃ content and the preservation of foraminiferal tests. High carbonate content occurs within the interval between 311.60 and 349.99 meters below seafloor, whereas CaCO₃ content was typically near 1 wt% for the rest of the core. In addition, benthic and planktonic foraminifers were relatively abundant. However, stable isotope measurements carried out within this interval contained unrealistic values, which we ascribe to postdepositional diagenetic alteration by the release of methane. This prohibited quantification of temperature, ice volume, and salinity. The CPE identified at Hole U1361A was also observed at Ocean Drilling Program Site 689, which is correlated to the Mi5 glaciation. We hypothesize that this Southern Ocean CPE and the diagenetic alteration of foraminifers were due to both the Mi5 glaciation and reorganization of ocean circulation. ¹ DeCesare, M., and Pekar, S., 2016. Data report: foraminiferal stable isotope and percent calcium carbonate analysis from IODP Expedition 318 Hole U1361A. In Escutia, C., Brinkhuis, H., Klaus, A., and the Expedition 318 Scientists, Proceedings of the Integrated Ocean Drilling Program, 318: Tokyo (Integrated Ocean Drilling Program Management International, Inc.). doi:10.2204/iodp.proc.318.202.2016 ² Department of Geology & Geophysics, Louisiana State University, E235 Howe Russell, Baton Rouge LA 70803, USA. mdeces3@lsu.edu ³ Department of Earth and Environmental Sciences, City University of New York, Queens College, 65–30 Kissena Blvd, Flushing NY 11367, USA. Initial receipt: 27 October 2014 Acceptance: 4 December 2015 Publication: 11 March 2016 MS 318-202 Top of page \| Previous \| Next