Trace elements and stable isotopes in bulk rocks and foraminifera, bulk
rock and clay mineral compositions, are used as palaeoproxies to
evaluate sea level fluctuations, climatic changes and variations in
primary productivity across the K-T transition at Elles 11 in Tunisia
from I m (similar to 33 kyr) below to I m (similar to 70 kyr) above the
K-T boundary. Results on clay minerals, major and trace elements, stable
isotopes in bulk rock samples (e.g. Ca, Cu, Zn, Rb, Sr, Zr, Ba,
delta(13)C and delta(18)O), and in foraminifera (Sr/Ca, delta(13)C,
delta(18)O) indicate that the latest Maastrichtian (last similar to 33
kyr) in Tunisia was marked by a relatively warm, but humid climate and a
rising sea level. The transgressive surface is marked by deposition of a
foraminiferal packstone just below the K-T boundary followed by maximum
flooding across the K-T boundary (red layer and black clay layer). Humid
warm conditions accompanied the maximum flooding, along with increased
total organic carbon values and rapidly decreasing primary productivity.
At the K-T boundary, an impact event (Ir anomaly, Ni-rich spinels,
spherules) exacerbated already stressed environmental conditions leading
to the mass extinction of tropical planktic foraminifera. Increasingly
more humid conditions prevailed within the lowermost Danian Zone PO
(similar to 50 kyr) culminating in a sea level lowstand near the top of
PO. A slow recovery of the ecosystem in Zone P1a coincided with arising
sea level and gradually less humid climatic conditions. (C) 2002
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