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Université de Fribourg

20th century minimum and maximum temperature variations analysed on a regional scale in Switzerland : statistical analyses of observational data

Jungo, Patricia ; Beniston, Martin (Dir.) ; Collet, Claude (Codir.) ; Frei, Christoph (Codir.) ; Wanner, Heinz (Codir.)

Thèse de doctorat : Université de Fribourg, 2001 ; no 1365.

The major aim of this study is to describe in a detailed manner the 20th century minimum and maximum temperature variations in Switzerland and to assess whether the magnitude of the secular warming and its interannual to interdecadal fluctuations show common seasonal patterns in different climatological regions. In a first step different climatological regions could successfully be...

Université de Fribourg

3D cartographic modeling of the Alpine Arc

Vouillamoz, Naomi ; Sue, Christian ; Champagnac, Jean-Daniel ; Philippe, Calcagno

In: Tectonophysics, 2012, p. -

We built a 3D cartography of the alpine arc, a highly non-cylindrical mountain belt, using the 3D GeoModeller of the BRGM (French geological survey). The model allows to handle the large-scale 3D structure of seventeen major crustal units of the belt (from the lower crust to the sedimentary cover nappes), and two main discontinuities (the Insubric line and the Crustal Penninic Front). It provides...

Université de Fribourg

Acoustic properties in travertines and their relation to porosity and pore types

Soete, J. ; Kleipool, , L.M. ; Claes, H. ; Claes, S. ; Hamaekers, H. ; Kele, S. ; Özkul, M. ; Foubert, Anneleen ; Reijmer, J.J.G. ; Swennen, R.

In: Marine and Petroleum Geology, 2015, vol. 59, p. 320–335

Sonic velocities of Pleistocene travertines were measured under variable confining pressures. Combined with petrographical characteristics and petrophysical data, i.e. porosity, permeability and density, it was determined that travertine porosity, pore types and cementation control compressional-wave (Vp) and shear-wave velocity (Vs). At 40 MPa confining...

Université de Fribourg

Age and synchronicity of planktonic foraminiferal bioevents across the Cenomanian – Turonian boundary interval (Late Cretaceous)

Falzoni, Francesca ; Petrizzo, Maria Rose ; Caron, Michèle ; Leckie, R. Mark ; Elderbak, Khalifa

In: Newsletters on Stratigraphy, 2018, vol. 51, no. 3, p. 343–380

The upper Cenomanian – lower Turonian is a key-stratigraphic interval, as it encompasses the Late Cretaceous supergreenhouse and a major perturbation of the global carbon cycle (i. e., Oceanic Anoxic Event 2) as evidenced by a global positive carbon isotope excursion and by the nearly world-wide deposition of organic-rich marine facies. A turnover in planktonic foraminiferal assemblages and...

Université de Fribourg

Analyse de l'activité de glissements de terrain et relation avec les conditions climatiques : exemples dans les Préalpes fribourgeoises (Suisse)

Oswald, Daniel ; Caron, Christian (Dir.) ; Raetzo, Hugo (Codir.) ; Müller, Imre (Codir.) ; Strasser, André (Codir.)

Thèse de doctorat : Université de Fribourg, 2003 ; no 1417.

Les glissements de terrain profonds (> 10 m) sont généralement caractérisés par des phases d'accélération alternant avec des périodes d'accalmie, mais le plus souvent sans montrer de réelle stabilisation. Il est donc difcile d'étudier l'évolution de l'activité compte tenu de la continuité des mouvements. Pour cela, une méthode d'analyse a été mise en place an de reconnaître...

Université de Fribourg

An analytical algorithm of porosity–permeability for porous and fractured media: extension to reactive transport conditions and fitting via flow-through experiments within limestone and dolomite

Erol, Selçuk ; Fowler, Sarah Jane ; Nehler, Mathias ; De Boever, Eva ; Harcouët-Menou, Virginie ; Laenen, Ben

In: Transport in Porous Media, 2019, vol. 129, no. 1, p. 343–383

Accurate prediction of permeability evolution is essential for forecasting the long-term performance and lifetime of hydrothermal reservoirs, an important goal in the geothermal, ore, and petroleum industries. Erol et al. (Transp Porous Media 120(2):327–358, 2017. https://doi.org/10.1007/s11242-017-0923-z) introduced a general (non-empirical) analytical Kozeny–Carman type equation for...

Université de Fribourg

Analyzing rockfall activity (1600–2002) in a protection forest—a case study using dendrogeomorphology

Stoffel, Markus ; Schneuwly, Dominique M. ; Bollschweiler, Michelle ; Lièvre, Igor ; Delaloye, Reynald ; Myint, Moe ; Monbaron, Michel

In: Geomorphology, 2005, vol. 68(3-4), p. 224

For the first time, dendrogeomorphology has been used to investigate spatial and temporal variations of rockfall activity in a protection forest. We report results of 564 cores from 135 severely injured Larix decidua Mill. trees on the west-facing Täschgufer slope, Swiss Alps. While trees sampled reached an age of 297 years on average, the oldest one attained breast height in AD 1318. For...