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Université de Fribourg

Microfossils, a key to unravel cold-water carbonate mound evolution through time: Evidence from the eastern alboran sea

Stalder, Claudio ; Vertino, Agostina ; Rosso, Antonietta ; Rüggeberg, Andres ; Pirkenseer, Claudius ; Spangenberg, Jorge E. ; Spezzaferri, Silvia ; Camozzi, Osvaldo ; Rappo, Sacha ; Hajdas, Irka

In: PLoS ONE, 2015, vol. 10, no. 10, p. e0140223

Cold-water coral (CWC) ecosystems occur worldwide and play a major role in the ocean's carbonate budget and atmospheric CO2 balance since the Danian (~65 m.y. ago). However their temporal and spatial evolution against climatic and oceanographic variability is still unclear. For the first time, we combine the main macrofaunal components of a sediment core from a CWC mound of the Melilla Mounds...

Université de Fribourg

A new Late Agenian (MN2a, Early Miocene) fossil assemblage from Wallenried (Molasse Basin, Canton Fribourg, Switzerland)

Mennecart, Bastien ; Yerly, Bertrand ; Mojon, Pierre-Olivier ; Angelone, Chiara ; Maridet, Olivier ; Böhme, Madelaine ; Pirkenseer, Claudius

In: Paläontologische Zeitschrift, 2015, p. 1–23

Excavations of two fossiliferous layers in the Wallenried sand- and marl pit produced a very diversified vertebrate fauna. New material allows the reassessment of the taxonomic position of the ruminant taxa Andegameryx andegaviensis and endemic Friburgomeryx wallenriedensis. An emended diagnosis for the second species is provided and additional material of large and small mammals, as well as...

Université de Fribourg

Paleocene–Eocene palaeoenvironmental conditions of the main phosphorite deposits (Chouabine Formation) in the Gafsa Basin, Tunisia

Kocsis, László ; Ounis, Anouar ; Baumgartner, Claudia ; Pirkenseer, Claudius ; Harding, Ian C. ; Adatte, Thierry ; Chaabani, Fredj ; Neili, Salah Mohamed

In: Journal of African Earth Sciences, 2014, vol. 100, p. 586–597

A detailed sedimentary section of the marine Chouabine Formation in the palaeogeographic Gafsa Basin, south-western Tunisia, was investigated in order to characterize environmental and depositional conditions focusing on the interval that spans the Paleocene–Eocene transition. We did stable isotope analyses of bulk sediments. Both phosphorite and carbonate yielded relatively similar isotopic...

Université de Fribourg

Late Weichselian deglaciation and early Holocene development of a cold-water coral reef along the Lopphavet shelf (Northern Norway) recorded by benthic foraminifera and ostracoda

Stalder, Claudio ; Spezzaferri, Silvia ; Rüggeberg, Andres ; Pirkenseer, Claudius ; Gennari, Giordana

In: Deep Sea Research Part II: Topical Studies in Oceanography, 2014, vol. 99, p. 249–269

Cold-water coral (CWC) settlement in northern Norway is strongly related to the outlet-glaciers of the Fennoscandian Ice-sheet, and dating of known CWC structures show clearly post-glacial ages. Two gravity cores (POS391 559/2,277 cm long and POS391 559/3,282 cm long) were recovered on a CWC reef in the area of Lopphavet, northern Norway. Detailed investigations on lithology (sediment structures...

Université de Fribourg

The position of the Rupelian/Chattian boundary in the southern Upper Rhine Graben based on new records of microfossils

Pirkenseer, Claudius ; Berger, Jean-Pierre ; Reichenbacher, Bettina

In: Swiss Journal of Geosciences, 2013, vol. 106, no. 2, p. 291–301

This study analyses the regressive phase of the marine Froidefontaine Subgroup and the subsequent fluvio-lacustrine Niederroedern formation in the southern Upper Rhine Graben during the Late Rupelian and the position of the Rupelian/Chattian boundary. The study is based on the sedimentary record and several microfossil groups from two boreholes, with a focus on new records of fish otoliths,...

Université de Fribourg

Reworked microfossils as a paleogeographic tool

Pirkenseer, Claudius ; Spezzaferri, Silvia ; Berger, Jean-Pierre

In: Geology, 2011, vol. 39, no. 9, p. 843-846

The abundant occurrence of reworked microfossils within the paleogeographically restricted Upper Rhine Graben of central Europe represents a unique opportunity to investigate their inherent information, allowing new insights into the paleogeographic framework and past sedimentary pathways. In the late Rupelian and early Chattian a transgression-regression cycle linked to the global Ru2–Ru3...

Université de Fribourg

New skeleton from the early Oligocene of Germany indicates a stem-group position of diomedeoidid birds

De Pietri, Vanesa L. ; Berger, Jean-Pierre ; Pirkenseer, Claudius ; Scherler, Laureline ; Mayr, Gerald

In: Acta Palaeontologica Polonica, 2010, vol. 55, no. 1, p. 23-34

We report a new specimen of the extinct procellariiform species Diomedeoides brodkorbi (Aves, Diomedeoididae) from the early Oligocene (Rupelian) of Rheinweiler in southwestern Germany. The well−preserved partial skeleton allows the recognition and reassessment of new osteological details that bear on the phylogenetic affinities of diomedeoidids. The presence on the coracoid of a deeply...

Université de Fribourg

Sédimentologie et paléontologie des paléoenvironnements côtiers rupéliens de la Molasse marine rhénane dans le Jura suisse

Picot, Laurent ; Becker, Damien ; Cavin, Lionel ; Pirkenseer, Claudius ; Lapaire, Frédéric ; Rauber, Gaëtan ; Hochuli, Peter A. ; Spezzaferri, Silvia ; Berger, Jean-Pierre

In: Swiss Journal of Geosciences, 2008, vol. 101, no. 2, p. 483-513

Les dépôts oligocènes marins, situés dans la partie distale du bassin molassique suisse et dans le prolongement sud du fossé rhénan, sont constitués par les groupes stratigraphiques suivants: les Conglomérats de Porrentruy, le Septarienton et le Meeressand. Cette série sédimentaire a fait l’objet d’études stratigraphiques, sédimentologiques et paléontologiques détaillées. Trois...

Université de Fribourg

Scanning electron microscope images of uncoated microfossils: applications, perspectives and limitations

Spezzaferri, Silvia ; Neururer, Christoph ; Pirkenseer, Claudius ; Grobéty, Bernard

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...