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Université de Fribourg

In situ measurements of Li isotopes in foraminifera

Vigier, Nathalie ; Rollion-Bard, Claire ; Spezzaferri, Silvia ; Brunet, Fabrice

In: Geochemistry Geophysics Geosystems, 2007, vol. 8, p. Q01003

In situ measurement of Li isotope ratios in foraminifera has been developed using a Cameca ims 1270 ion microprobe. In situ δ⁷Li analyses have been performed in biogenic calcite of planktonic foraminifera from various locations. Results show that for west Pacific mixed Globigerinoides and Globorotalia (22°S161°E), the isotopic variability between tests and within a...

Université de Fribourg

Scanning electron microscope documentation of the lost holotypes of Mornod, 1949: Thalmanninella reicheli and Rotalipora montsalvensis

Caron, Michèle ; Spezzaferri, Silvia

In: The Journal of Foraminiferal Research, 2006, vol. 36, no. 4, p. 374-378

The species Globotruncana (Rotalipora) reicheli and Gobotruncana (Rotalipora) montsalvensis, were established in 1949 by Mornod. The two holotypes were figured only by drawings and the specimens were never made publicly available. Since their first description, these two species have acquired great importance as biostratigraphic markers. However, holotypes had been considered as...

Université de Fribourg

Bolboforma (Phytoplankton Incertae Sedis), Bachmayerella and other Calciodinelloidea (Phytoplankton) from the Middle Miocene of the Alpine–Carpathian Foredeep (Central Paratethys)

Spezzaferri, Silvia ; Rögl, Fred

In: Journal of Micropalaeontology, 2004, vol. 23(2), p. 139

Bolboforma is a microfossil of uncertain origin with affinities to protophytic algae. It generally occurs at high latitudes and/or in cool and temperate waters and has a high stratigraphic potential especially for the Miocene. Calcareous cysts of dinoflagellates represent the ‘benthic cyst stage’ of unicellular organisms belonging to the marine phytoplankton.The occurrence of...