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
The Early Jurassic dinosaur site of Toundoute which yielded the basal sauropod Tazoudasaurus naimi is examined in the light of its stratigraphic, sedimentological and palaeoenvironmental context. A thin succession of Early Liassic marine carbonates (probably Hettangian-Sinemurian in age) is continuously overlain by continental beds with dinosaurs. These latter are assumed to be of Middle to Late...
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In: Eclogae Geologicae Helvetiae, 2005, vol. 98, no. 2, p. 281-296
Located in the distal part of the Swiss Molasse Basin and in the southern extension of the Rhine Graben, the conglomeratic deposits belonging to the Gompholithes & Conglomérats stratigraphic group have been the object of detailed sedimentological and paleontological studies. The great number of outcrops that came into sight during the building works of the Transjurane highway in the vicinity...
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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.
Slope instabilities such as mudflows, debris flows or landslides have lately raised much concern in Switzerland, since various major events have occurred during the last decade, resulting in major landscape disturbances, as well as costly damage to infrastructure. This demonstrated the necessity to better understand the causes and dynamics of such processes. This research work aims at defining...
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