Cell ultrastructure and formation of coccoliths
in Cyclococcolithina leptopora (Murray and Blackman) Wilcoxon and Gephyrocapsa oceanica Kamptner.
The central protagonist of this story is an anthropomorphic representation of the microscopic unicellular plankton (coccolithophores) whose test consists of calcium carbonate scales (coccoliths
); beds of chalk are the result of the accumulation of these coccoliths
on the ocean floor over millions of years.
A filtration technique for quantitative studies of coccoliths
A comparison of water samples and sediments across a variety of locations has shown that the weight of individual coccoliths
(mainly those of Emiliania huxleyi, the most common coccolithophore species, and Gephyrocapsa) increases as seawater [C[O.
The algae form pale chalky cases called coccoliths
, which during the spring bloom can be seen, from space in the seas around the UK.
Notes on Neogene calcareous nannofossil biostratigraphy of the Ontong Java Plateau and size variations of Reticulofenestra coccoliths
Other promising proxies are: the Sr/Ca ratio in coccoliths
, which correlates with rates of organic carbon fixation and calcifcation; [delta][sup.
2) A large group of very small marine algae 2-20 microns in size, covered with calcareous chalky scales known as coccoliths
Nicholls (1979), using X-ray emission spectra, has shown that the scales are composed of silica, but not calcified, and hence do not represent coccoliths
Nannoplankton fruto the Galapagos Islands: Michaelsarsia elegans Gran and Haloppapus adriaticus Schiller (coccolithophorids) with special reference to coccoliths
and their unmineralized comoponents.
More than 80% of the coccoliths
that accumulate in the sediments of the Mediterranean are E.
The sedimentary origin of the calcareous components is proved by the presence of coccoliths
, fossils of marine algae that lived in past geological eras but not at present (Danin et al.