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Data
96 datasets found! (Query time: 3 ms)
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Sluijs, A; Schouten, S; Pagani, M et al. (2006): (Table S1) Palynology of IODP Hole 302-M0004A
| Abstract: |
The Palaeocene/Eocene thermal maximum, 55 million years ago, was a brief period of widespread, extreme climatic warming (Zachos et al., 2003; Kennett and Stott, 1991, doi:10.1038/353225a0; Tripati and Elderfield, 2005, doi:10.1126/science.1109202), that was associated with massive atmospheric greenhouse gas input (Dickens et al., 1995, doi:10.1029/95PA02087). Although aspects of the resulting environmental changes are well documented at low latitudes, no data were available to quantify simultaneous changes in the Arctic region. Here we identify the Palaeocene/Eocene thermal maximum in a marine sedimentary sequence obtained during the Arctic Coring Expedition (Backman et al., 2006, doi:10.2204/iodp.proc.302.2006). We show that sea surface temperatures near the North Pole increased from 18 °C to over 23 °C during this event. Such warm values imply the absence of ice and thus exclude the influence of ice-albedo feedbacks on this Arctic warming. […] |
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1185 data points |
https://doi.org/10.1594/PANGAEA.769815 - Score: 8.683
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Ogawa, Y; Takahashi, K; Yamanaka, T et al. (2009): (Appendix A) Geochemistry for Units 1/6, 2, and the upper part of Unit 3 of IODP Holes 302-M0002A and 302-M0004A
| Abstract: |
Integrated Ocean Drilling Program (IODP) Expedition 302 Arctic Coring Expedition (ACEX) obtained the first relatively continuous long sediment cores from the Lomonosov Ridge in the central Arctic Ocean in 2004. Preceding microfossil studies indicated the dominance of low salinity surface waters in the early to middle Eocene Arctic basin. The main purpose of this study is to reconstruct paleoceanographic conditions including the extent of saline (seawater) mass presence. To attain this goal we performed geochemical analyses of total sulfur (%TS), total organic carbon (%TOC) and stable sulfur isotopic composition (d34S) on the early to middle Eocene section of the ACEX cores. The %TS were high in all the examined intervals and the sedimentary sulfur occurred mainly as framboidal pyrite, indicating that sufficient sulfate, indicative of seawater, was present in the deep layer of the paleo-Arctic basin and that the pyrite was formed in the sediments under sufficient iron input. […] |
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909 data points |
https://doi.org/10.1594/PANGAEA.785796 - Score: 8.683
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Eynaud, F (2011): Planktonic foraminifera and microfossil composition of IODP Hole 302-M0004C
| Abstract: |
Calcareous microfossils are widely used by paleoceanographers to investigate past sea-surface hydrology. Among these microfossils, planktonic foraminifera are probably the most extensively used tool (e.g. [1] for a review), as they are easy to extract from the sediment and can also be used for coupled geochemical (e.g; d18O, d13C, Mg/Ca) and paleo-ecological investigations. Planktonic foraminifera are marine protists, which build a calcareous shell made of several chambers which reflect in their chemistry the properties of the ambient water-masses. Planktonic foraminifera are known to thrive in various habitats, distributed not only along a latitudinal gradient, but also along different water-depth intervals within surface waters (0-1000 m). Regarding their biogeographical distribution, planktonic foraminifera assemblages therefore mirror different water-masses properties, such as temperature, salinity and nutrient content of the surface water in which they live. […] |
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3709 data points |
https://doi.org/10.1594/PANGAEA.788078 - Score: 8.683
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Sluijs, A; Röhl, U; Schouten, S et al. (2008): (Table 1) Elemental mean values of the upper Paleocene and lower Eocene in IODP Hole 302-M0004A
| Abstract: |
We reconstruct the latest Paleocene and early Eocene (~57-50 Ma) environmental trends in the Arctic Ocean and focus on the Paleocene-Eocene thermal maximum (PETM) (~55 Ma), using strata recovered from the Lomonosov Ridge by the Integrated Ocean Drilling Program Expedition 302. The Lomonosov Ridge was still partially subaerial during the latest Paleocene and earliest Eocene and gradually subsided during the early Eocene. Organic dinoflagellate cyst (dinocyst) assemblages point to brackish and productive surface waters throughout the latest Paleocene and early Eocene. Dinocyst assemblages are cosmopolitan during this time interval, suggesting warm conditions, which is corroborated by TEX86'-reconstructed temperatures of 15°-18°C. Inorganic geochemistry generally reflects reducing conditions within the sediment and euxinic conditions during the upper lower Eocene. […] |
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125 data points |
https://doi.org/10.1594/PANGAEA.733796 - Score: 8.583
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Cronin, TM; Smith, SA; Eynaud, F et al. (2008): Age determination and stable carbon isotope ratios of Neogloboquadrina pachyderma of IODP Hole 302-M0004C
| Abstract: |
The Integrated Ocean Drilling Program (IODP) Arctic Coring Expedition (ACEX) Hole 4C from the Lomonosov Ridge in the central Arctic Ocean recovered a continuous 18 m record of Quaternary foraminifera yielding evidence for seasonally ice-free interglacials during the Matuyama, progressive development of large glacials during the mid-Pleistocene transition (MPT) ~1.2-0.9 Ma, and the onset of high-amplitude 100-ka orbital cycles ~500 ka. Foraminiferal preservation in sediments from the Arctic is influenced by primary (sea ice, organic input, and other environmental conditions) and secondary factors (syndepositional, long-term pore water dissolution). Taking these into account, the ACEX 4C record shows distinct maxima in agglutinated foraminiferal abundance corresponding to several interglacials and deglacials between marine isotope stages (MIS) 13-37, and although less precise dating is available for older sediments, these trends appear to continue through the Matuyama. […] |
| Size: |
30 data points |
https://doi.org/10.1594/PANGAEA.706303 - Score: 8.483
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Vogt, C (2008): Relative mineral abundances from bulk fraction X-ray diffraction data of Hole 302-M0003A
https://doi.org/10.1594/PANGAEA.704657 - Score: 7.911
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Boucsein, B (2008): Macerals of Hole 302-M0004A
https://doi.org/10.1594/PANGAEA.690519 - Score: 7.911
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Onodera, J; Takahashi, K (2012): (Table 2) Mean abundance of ebridian taxa in each ebridian assemblage group from IODP Exp302
https://doi.org/10.1594/PANGAEA.787524 - Score: 7.911
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O'Regan, M; Sakamoto, T; King, JW (2008): (Table 4) Correlation tie points of Exp302 (ACEX) composite depth scale and cores 96/12-1PC and PS2185-6
https://doi.org/10.1594/PANGAEA.707039 - Score: 7.911
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Krylov, AA; Andreeva, IA; Vogt, C et al. (2008): (Table 2) Relative abundance of autigenic minerals of Hole 302-M0002A
https://doi.org/10.1594/PANGAEA.707422 - Score: 7.911
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