Micropalaeontological dating of the basal Cretaceous section of DSDP Site 249, Leg 25, Mozambique Ridge: implications for the timing of the southern Atlantic–Indian Ocean connection
R. Dunay, W. Braham, M. K. E. Cooper, Martin Lester, F. Tremolada
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引用次数: 3
Abstract
Abstract. Tectonic models suggest the absence of a deep water connection on the
Mozambique Ridge during early Neocomian time. These models imply the
initiation of a deep water connection between the southern Atlantic and
Indian oceans formed during Barremian–earliest Aptian times. However,
previous biostratigraphic studies of the earliest deep water sediments on the
Mozambique Ridge suggest that the basal section is Neocomian in age. Here, we
present a new biostratigraphic analysis undertaken to test this tectonic
model and determine the earliest age of deep water sedimentation on the
Mozambique Ridge. Core samples from the Cretaceous interval
222.05–406.32 m (Cores 19–32) of DSDP Site 249, Leg 25, were
sampled for calcareous nannoplankton and palynological analysis. Most of the
sampling was concentrated on the Lower Cretaceous interval below
294 m . Our results indicate that the lower sedimentary section is no
older than Barremian and therefore provides support for the age proposed by
the tectonic models.
期刊介绍:
The Journal of Micropalaeontology (JM) is an established international journal covering all aspects of microfossils and their application to both applied studies and basic research. In particular we welcome submissions relating to microfossils and their application to palaeoceanography, palaeoclimatology, palaeobiology, evolution, taxonomy, environmental change and molecular phylogeny.