|Coccolithophores in the upper Quaternary of some Southeast Indonesian Basins|
Biekart, J.W. (1989). Coccolithophores in the upper Quaternary of some Southeast Indonesian Basins. Neth. J. Sea Res. 24(4): 523-530
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579, more
Well-preserved, late Quaternary calcareous nannofossil floras were found in three piston cores collected during the Snellius-II Expedition (1984-1985) in Indonesian waters. In particular, the high numbers of unusual species like Reticulofenestra parvula and Dictyococcites sessilis is conspicious. In all the cores Florisphaera profunda, a deep-living species, is dominant. According to oxygen isotope analysis of the nannoplankton carbonate the oldest core has an age of 300 ka approximately, whilst the other two cores reach an age of ca 80 ka; 14C dating and biostratigraphical results confirm these ages. Gephyrocapsa sp. aff. G. ericsonii vanishes between 17 and 14 ka BP in all the three cores. Only in one core, some species frequencies seem to reflect Pleistocene climatic cycles. Principal components analysis indicates a correlation between the group of species consisting of Gephyrocapsa oceanica, Florisphaera profunda and Reticulofenestra parvula and the δ13C record. This correlation is tentatively interpreted in terms of fertility. The results of this study suggest that only weak changes in the palaeoenvironmental conditions occurred during the time span studied. Those changes which seem to be significant are not related to temperature, but probably to fertility or other environmental factors.