Sr, C and O isotope ratios of Neogene sediments from DSDP Hole 38-341, Voring Plateau ...
The Neogene sediments from DSDP site 341 on the Voring Plateau, Norwegian Sea, contain a thin glauconitic pellet-bearing subunit, which separates underlying pelagic clays from overlying glacial-marine sediments. Oxygen isotope measurements of benthic foraminifera show a delta18O shift of + 1 per mil...
| Main Authors: | , , |
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| Format: | Article in Journal/Newspaper |
| Language: | English |
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PANGAEA
1986
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| Subjects: | |
| Online Access: | https://dx.doi.org/10.1594/pangaea.714252 https://doi.pangaea.de/10.1594/PANGAEA.714252 |
| Summary: | The Neogene sediments from DSDP site 341 on the Voring Plateau, Norwegian Sea, contain a thin glauconitic pellet-bearing subunit, which separates underlying pelagic clays from overlying glacial-marine sediments. Oxygen isotope measurements of benthic foraminifera show a delta18O shift of + 1 per mil during deposition of this subunit, probably a combined effect of a drop in bottom water temperature and a rise in seawater delta18O. The chronology of this sedimentological and O isotope transition is, however, poorly constrained by fossil evidence.Rb-Sr dating of glauconitic pellets indicates that the lower part of the glauconitic subunit was deposited 11.6 +/- 0.2 Ma ago. Further geochronological evidence, derived from the Sr and C isotopic compositions of foraminifera compared with known seawater-time variations, indicates that the lower pelagic clays are early to middle Miocene, deposited at a mean rate of ~15 m/Ma. The glauconitic subunit contains part of the middle Miocene and probably all of the late ... : Supplement to: Smalley, P Craig; Nordaa, A; Raheim, A (1986): Geochronology and paleothermometry of Neogene sediments from the Voring Plateau using Sr, C and O isotopes. Earth and Planetary Science Letters, 78(4), 368-378 ... |
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