Foraminifera source details
Huber, B. T. (1990). Maestrichtian Planktonic Foraminifer Biostratigraphy of the Maud Rise (Weddell Sea|Antarctica): ODP Leg 113 Holes 689B and 690C. Proceedings of the Ocean Drilling Program, Scientific Reports. 113 : 489-514.
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10.2973/odp.proc.sr.113.135.1990 [view]
Huber, B. T.
1990
Maestrichtian Planktonic Foraminifer Biostratigraphy of the Maud Rise (Weddell Sea|Antarctica): ODP Leg 113 Holes 689B and 690C
Proceedings of the Ocean Drilling Program, Scientific Reports
113 : 489-514
Publication
The southernmost record of Maestrichtian pelagic carbonate sedimentation was recovered from ODP Leg 113 Holes
689B and 690C, drilled on the Maud Rise in the eastern Weddell Sea sector of the Southern Ocean (65°S). Well pre
served and abundant planktonic foraminifers occur throughout Maestrichtian cores from both holes, providing a nearly
complete biogeographic and biostratigraphic history of this region. Diversity is low compared to tropical and subtropi
cal assemblages, with a maximum within sample diversity of 16 planktonic foraminifer species and a diversity total for
the Maestrichtian of 24 species. The assemblages are dominated throughout by
Heterohelix, Globigerinelloides,
and a
new species of
Archaeoglobigerina,
whereas keeled taxa are completely absent from the lower Maestrichtian and rare in
the middle through upper Maestrichtian sediments.
Three planktonic foraminifer species are described as new and are recognized as being endemic to the Austral Prov
ince.
These include
Archaeoglobigerina australis
n. sp.,
Hedbergella sliteri
n. sp., and
Archaeoglobigerina mateola
n.
sp.
The former two species were previously illustrated in reports on Late Cretaceous foraminifers from the Falkland Pla
teau and the northern Antarctic Peninsula. Two keeled and five non-keeled planktonic foraminifers, previously not
found in high latitude Maestrichtian sediments, first appeared at the Maud Rise during the late early and late Maes
trichtian. Correlation with their stratigraphic ranges in low latitude sequences shows that their first appearance datums
are considerably younger at the Maud Rise than in the lower latitudes. The most likely explanation for this observation
is that there was a warming in the south polar region during the late early and late Maestrichtian and a concomitant
poleward migration of stenothermal taxa. However, oxygen isotopic paleotemperature results from Sites 689 and 690
(Barrera and Huber, this volume) show a long-term cooling trend throughout the Maestrichtian, indicating that other
factors may have played a more important role than temperature in the distribution of Maestrichtian planktonic fora
minifers.
A new biostratigraphic scheme is proposed for the Antarctic because of the absence of thermophilic planktonic for
aminifers used to identify existing low to middle latitude zones. The
Globigerinelloides impensus
Partial Range Zone is
defined for the late Campanian-Maestrichtian, the
Globotruncanita havanensis
Partial Range Zone is redefined for the
early to late early Maestrichtian, and the
Abathomphalus mayaroensis
Total Range Zone is recognized. Good quality
magnetic polarity data obtained from both Maud Rise sites (Hamilton, this volume) enables magnetobiostratigraphic
correlation of twelve foraminifer datums with the geomagnetic polarity time scale of Haq et al. (1987). The geochronol
ogy thus obtained is crucial for accurate cross-latitudinal correlation and interpretation of the paleoceanographic his
tory of the Antarctic region during the Maestrichtian time period.
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Archaeoglobigerina australis Huber, 1990 † (original description)
Archaeoglobigerina mateola Huber, 1990 † (original description)
Hedbergella sliteri Huber, 1990 † accepted as Muricohedbergella sliteri (Huber, 1990) † (original description)
Archaeoglobigerina mateola Huber, 1990 † (original description)
Hedbergella sliteri Huber, 1990 † accepted as Muricohedbergella sliteri (Huber, 1990) † (original description)