In: Chemical Geology, 2007, vol. 244, no. 3-4, p. 679-690
An analytical procedure has been developed for the in situ measurement of calcium isotope composition of carbonates with a spatial resolution of 15–20 μm on a Caméca IMS 1270 ion microprobe. By using two Faraday cup detectors, the ⁴⁰Ca and ⁴⁴Ca can be measured simultaneously, improving the internal reproducibility. Instrumental mass fractionation (IMF) of calcium isotopes was...
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In: The Journal of Foraminiferal Research, 2007, vol. 37, no. 3, p. 270-276
We present a recently developed method using a field emission scanning electron microscope (FEG) to view and photograph microfossil specimens that are not coated by conductive material. The FEG microscope provides high electron flux and offers the option to capture images at low beam voltage. Balancing incident energy with absorbed energy from the detector leads to charge-free images of...
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In: International Journal of Earth Sciences, 2007, vol. 96, no. 3, p. 567-591
Ammonite biostratigraphy plays a central role in the definition of Jurassic stratigraphy. Nevertheless, the strong provincialism of European ammonite species during the Kimmeridgian is a long-standing problem in correlation attempts between the boreal and Tethyan faunal realms. Moreover, the sequence-stratigraphic interpretations for northern and southern Europe given in the Jurassic...
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In: Journal of Vertebrate Paleontology, 2007, vol. 27, no. 3, p. 610–624
The fossil record of abelisauroid carnivorous dinosaurs was previously restricted to Cretaceous sediments of Gondwana and probably Europe. The discovery of an incomplete specimen of a new basal abelisauroid, Berberosaurus liassicus, gen. et sp. nov., is reported from the late Early Jurassic of Moroccan High Atlas Mountains. Phylogenetic analysis recovers Ceratosauroidea and Coelophysoidea as...
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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...
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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...
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In: Eclogae Geologicae Helvetiae, 2006, vol. 98, no. 2, p. 261-270
Le gisement de dinosauriens du Jurassique inférieur de Toundoute, à sauropode primitif (Tazoudasaurus naimi), est examiné sous ses aspects stratigraphiques, sédimentologiques et paléoenvironnementaux. Les couches continentales détritiques à dinosaures, succédant en continuité à des niveaux marins carbonatés trés peu épais du Lias inférieur (Hettangien-Sinémurien probables), sont...
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In: Eclogae Geologicae Helvetiae, 2005, vol. 98, no. 2, p. 281-296
Situés dans la partie la plus distale du bassin molassique suisse et dans le prolongement sud du fossé rhénan, les dépôts conglomératiques appartenant au groupe stratigraphique des Gompholithes & Conglomérats ont fait l’objet d’une étude sédimentologique et paléontologique détaillée. La multitude des affleurements réalisés lors des travaux de construction de l’autoroute...
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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...
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Thèse de doctorat : Université de Fribourg, 2002 ; no 1395.
L'accroissement des fréquences et de l'impact de processus d'instabilités de terrain tels que des coulées de boue, laves torrentielles, glissements de terrain ou éboulements, au cours de la dernière décennie, a démontré la nécessité de mieux connaître les causes et la dynamique de ces processus. Ce travail de recherche s'inscrit dans une démarche visant à préciser les relations...
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