| Summary: | Svalbard locates along the De Geer Transform Fault that separates the kinematics of North Atlantic and Arctic Ocean and are a continental rise along the North Atlantic portion of this transform. A fold and thrust belt of Paleogene age boards theWestern margin of the Spitsbergen with a NNW-SSE trend. In the ‘60s theWest – Spitsbergen fold and trust belt was related to the relative movements between Laurentia and Eurasia. Specifically, it was regarded to be a transpressive orogen developed at the intra-continental De Geer Transform margin between the Barents and the Greenland Shelves. This setting was suggested by the necessity of a continental transform off the western margin of Svalbard needed to restore the relative openings of the North Atlantic-Arctic Ocean basins, and the Paleogene age of the fold-belt. Later structural studies in other areas of Svalbard suggested that convergent tectonics have been prevailing during much of the fold and thrust development. However this belt can hardly be regarded as a classical orogen resulting from an active continental margin for the lack of evidence for subduction, synorogenic magmatism, metamorphism or a thickened crust. On the other hand, it would be difficult to merely relate this fold and thrust belt to the De Geer Transform Fault. According to Authors a transform fault should produce structures with vergence away from the fault on both sides, whereas the found direction of tectonic transport in North Greenland is the same as in Spitsbergen, i.e. to the E and NE. In this way the transform separation of North-Greenland and Spitsbergen should postdate the formation of the Tertiary North-Greenland and Spitsbergen fold and trust belt. This rises the question on possible Neogene-Quaternary tectonics in Spitsbergen. Evidence for this younger tectonics includes the occurrence of Quaternary volcanism and thermal springs in the northern part of Spitsbergen and the moderate seismicity in Nordaustlandet. Other clues supporting a recent tectonics derive from the analysis of ...
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