Distribution of Cretaceous and early Danian planktonic foraminifera in ODP Hole 119-738C (Table 1) ...
A biostratigraphically complete upper Maestrichtian-Danian sequence was recovered at ODP Leg 119 Site 738 on the southern Kerguelen Plateau (62°S). Planktonic foraminifers are abundant and well to moderately preserved in all upper Maestrichtian samples to within 6 cm of the Cretaceous/Tertiary bound...
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Format: | Dataset |
Language: | English |
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PANGAEA - Publishing Network for Geoscientific and Environmental Data
1991
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Online Access: | https://dx.doi.org/10.15468/deupb5 https://www.gbif.org/dataset/79f1c49c-f762-11e1-a439-00145eb45e9a |
Summary: | A biostratigraphically complete upper Maestrichtian-Danian sequence was recovered at ODP Leg 119 Site 738 on the southern Kerguelen Plateau (62°S). Planktonic foraminifers are abundant and well to moderately preserved in all upper Maestrichtian samples to within 6 cm of the Cretaceous/Tertiary boundary, where foraminifers are rare and poorly preserved due to increased sediment lithification. Lowermost Danian samples are also poorly preserved, but specimen abundance is sufficient for preliminary quantitative biostratigraphic analysis. Despite the poor foraminifer preservation, evidence is presented for paleoenvironmental change immediately below a thin, iridium-rich calcareous clay horizon that is recognized as the Cretaceous/Tertiary boundary. The most significant indicators for preboundary change include; (1) loss of sediment bioturbation; (2) loss of keeled planktonic foraminifers; and (3) diminished size and diversity of benthic foraminifers. Planktonic foraminifers showing transitional morphologies ... |
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