(Table 2) Geochemical analysis from IODP Exp302 ...

• Main Authors: Ogawa, Yusuke, Takahashi, Kozo, Yamanaka, Toshiro
• Format: Dataset
• Language: English
• Published: PANGAEA 2012
• Subjects: Event label; Sample code/label; DEPTH, sediment/rock; Opal, biogenic silica; Accumulation rate, opal; Carbon, organic, total; Sulfur, total; Nitrogen, total; δ34S; Carbon/Nitrogen ratio; DSDP/ODP/IODP sample designation; Opal, extraction; Mortlock & Froelich, 1989; Spectrophotometer Shimadzu UV mini-1240; Element analyser CHNS/O, Perkin-Elmer 2400 II; Mass spectrometer GV Instruments Isoprime; Exp302; CCGS Captain Molly Kool Vidar Viking; Integrated Ocean Drilling Program / International Ocean Discovery Program IODP; Arctic Basin; Arctic Ocean; Paleo-Arctic
• Online Access: https://dx.doi.org/10.1594/pangaea.787402; https://doi.pangaea.de/10.1594/PANGAEA.787402

Geochemical analyses of biogenic opal, total organic carbon (TOC), total sulfur (TS), and stable sulfur isotopic composition were conducted on the middle Eocene section of the ACEX cores obtained by IODP Expedition 302. The analyzed %TS contents were high in all the examined intervals, indicating sufficient sea water was present in the deep layer of the paleo Arctic basin in contrast with the low salinity surface waters determined by freshwater siliceous microfossils. From the high %TS in Lithological Unit 1/6, the extent of sea water supply from outside of the Arctic basin appeared to have increased after 45 Ma. The euxinic condition of the bottom water is suggested by the TOC-TS diagram. The anoxic environment was brought about by the estuarine type circulation pattern and salinity stratification. The light sulfur isotope composition (d34S) indicates the microbial sulfate reduction in an open system. The trend of d34S shift toward lower values with time is an indication of the history that the water ... : Supplement to: Ogawa, Yusuke; Takahashi, Kozo; Yamanaka, Toshiro (2008): Paleoceanography of the middle Eocene Arctic Ocean based on geochemical measurements of biogenic matter. Memoirs of the Faculty of Science Kyushu University Series D Earth and Planetary Sciences, 32(1), 31-48 ...