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Université de Fribourg

Greenland – Norway separation: A geodynamic model for the North Atlantic

Mosar, Jon ; Eide, Elizabeth A. ; Osmundsen, Per Terje ; Sommaruga, Anna ; Torsvik, Trond H.

In: Norwegian Journal of Geology, 2002, vol. 82, p. 282-299

Combining information from onshore and offshore Mid-Norway, we propose a structural model for the Scandinavian North Atlantic passive margin from Permo- Carboniferous through Present. We re-examine the role of post-Permo-Carboniferous normal faults and define an innermost boundary fault system forming the continentward limit of the rifted margin. Crustal-scale cross-sections of the Greenland-...

Université de Fribourg

Reconstructions of the continents around the North Atlantic at about the 60th parallel

Torsvik, Trond H. ; Van der Voo, Rob ; Meert, Joseph G. ; Mosar, Jon ; Walderhaug, Harald J.

In: Earth and Planetary Science Letters, 2001, vol. 187(1-2), p. 55

Late Carboniferous–Early Tertiary apparent polar wander (APW) paths (300–40 Ma) for North America and Europe have been tested in various reconstructions. These paths demonstrate that the 500 fathom Bullard et al. fit is excellent from Late Carboniferous to Late Triassic times, but the continental configuration in northern Pangea changed systematically between the Late Triassic (ca. 214 Ma)...

Université de Fribourg

Cretaceous-Tertiary geodynamics: a North Atlantic exercise

Torsvik, Trond H. ; Mosar, Jon ; Eide, Elizabeth A.

In: Geophysical Journal International, 2001, vol. 146, no. 3, p. 850-866

New reconstructions are presented for the Cretaceous–Early Tertiary North Atlantic using a combination of palaeomagnetic, hotspot and magnetic anomaly data. We utilize these reconstructions in an analysis of previously described misfits between the North Atlantic Plate elements at successive intervals during this time period. We are able to achieve reasonable overlap between the hotspot and...

Université de Fribourg

Depth of extensional faulting on the Mid-Norway Atlantic passive margin

Mosar, Jon

In: Norges geologiske undersøkelse Bulletin, 2000, vol. 437, p. 33-43

Two crustal-scale cross-sections of the Mid-Norwegian Atlantic passive margin are discussed. Large W- and E-dipping normal faults relate to extension of the continental crust following the Caledonian orogeny and the subsequent opening of the Atlantic Ocean. The passive margin extends from the ocean-continent boundary west of the Vøring Marginal High to the innermost extensional normal faults...

Université de Fribourg

North Atlantic sea-floor spreading rates: implications for the Tertiary development of inversion structures of the Norwegian–Greenland Sea

Mosar, Jon ; Lewis, Gavin ; Torsvik, Trond H.

In: Journal of the Geological Society, 2002, vol. 159, no. 5, p. 503-515

Tertiary development of the Norwegian continental margin was dominated by the opening of the Arctic–North Atlantic Ocean. The correct identification of magnetic anomalies and their ages and the analysis of spreading rates during the formation of this ocean are important in understanding the development of the region and specifically the history of its passive margins. Three ocean domains,...

Université de Fribourg

Palaeotectonic and palaeogeographic evolution of the western Tethys and PeriTethyan domain (IGCP Project 369)

Stampfli, G. M. ; Borel, G. D. ; Cavazza, W. ; Mosar, Jon ; Ziegler, P. A.

In: Episodes, 2001, vol. 24, no. 4, p. 222-228

Project No. 369 ("Comparative Evolution of PeriTethyan Rift Basins") of the International Geological Correlation Program produced a new palaeotectonic- palaeogeographic atlas of the western PeriTethyan domain. The atlas contains more than two hundred new maps and documents grouped in nine regional sets (Iberia, Polish Trough, Eastern European and Scythian Platforms, Moesian Platform, Levant, ...

Université de Fribourg

Present-day and future tectonic underplating in the western Swiss Alps: reconciliation of basement / wrench-faulting and décollement folding of the Jura and Molasse basin in the Alpine foreland

Mosar, Jon

In: Earth and Planetary Science Letters, 1999, vol. 173, no. 3, p. 143-155

The western Alps form a geodynamically active mountain belt showing the typical features of an evolving orogenic wedge with its pro-wedge geometry to the NNW and its retro-wedge structures to the SSE. Renewed tectonic underplating of European continental crust occurred after the orogenic wedge underwent major dynamic disequilibrium following the break-off of the southward subducting slab of the...

Université de Fribourg

Carbonate Sedimentation Rates Today and in the Past: Holocene of Florida Bay, Bahamas, and Bermuda vs. Upper Jurassic and Lower Cretaceous of the Jura Mountains (Switzerland and France)

Strasser, André ; Samankassou, Elias

In: Geologia Croatica, 2003, vol. 56, no. 1, p. 1-18

Lagoonal to intertidal sediments from the Holocene in Florida Bay, on the Bahamas, and in Bermuda are compared to similar facies in the Kimmeridgian and Berriasian of the Swiss and French Jura Mountains. Dating by 14C permits the estimation of sediment accumulation rates in the Holocene. In the ancient outcrops, the timing is given by cyclostratigraphic analysis. Elementary depositional...

Université de Fribourg

Instabilité de terrain dans les Préalpes fribourgeoises (Suisse) au cours du Tardiglaciaire et de l'Holocène : influence des changements climatiques, des fluctuations de la végétation et de l'activité humaine

Dapples, Florence ; Caron, Christian (Dir.) ; Raetzo, Hugo (Codir.) ; Kienholz, Hans (Codir.) ; Strasser, Andreas (Codir.)

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...

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...