TranScand 2018

Cuthbert, S. (Invited speaker)

Activity: Participating in or organising an eventParticipation in workshop, seminar, course

Description

Collisional Orogeny in the Scandinavian Caledonides (COSC): Excursion / Workshop across the central part of the Scandes - Jämtland (Sweden) and Möre-Trøndelag (Norway)

The TRANSCAND-2018 Excursion/Workshop crosses the central part of the Scandes from the Caledonian front, near Östersund in Sweden, to Trondheim and Molde on the Norwegian west coast. It is designed to demonstrate the basic structure of the Scandinavian mountain belt - the thrust-sheets (allochthons), their internal structure, stratigraphy, metamorphism and intrusions. It starts in the Autochthon on the Baltoscandian Platform and examines the evidence that the overlying Lower Allochthon is derived from the edge of this shelf and Caledonian foreland basin(s). These Jämtlandian nappes are overridden by the Middle Allochthon, which is inferred to have been transported from the outer parts of the Baltoscandian margin, including COT. The upper units of the Middle Allochthon (Seve Nappe Complex, SNC) contains eclogites, garnet peridotites and garnetiferous gneisses with micro-diamonds; they are estimated to have been transported, after Ordovician subduction and accretion, from at least 400 km west of their present locations during Scandian collisional orogeny. The overlying Upper and Uppermost allochthons are outboard terranes and have moved much further, having originated in the Iapetus Ocean and along the outer continental margin of Laurentia, respectively. The excursion ends in the early Devonian UHP rocks of Norway´s Western Gneiss Region (WGR).
Collisional Orogeny in the Scandinavian Caledonides (COSC): Excursion / Workshop across the central part of the Scandes - Jämtland (Sweden) and Möre-Trøndelag (Norway)

In the Scandes, we can try to understand what happens at depth when one continent (Baltica) underthrusts another (Laurentia), with vast horizontal displacements, thickening of continental crust and mountain building. The Transcand profile across the central Scandes allows us to examine the fossilized processes that occurred from the Neoproterozoic to the Devonian. On the basis of this evidence, we will use the experience of our participants to test the hypothesis that the Scandinavian Caledonides, as a part of the North Atlantic Caledonides, represent a useful analogue for the deeper levels of the crust beneath the Himalaya-Tibet Orogen today.

I acted as excursion leader for the last day of the excursion.

Period5 Aug 2018 - 15 Aug 2018
Event typeWorkshop
LocationMolde, Norway
Degree of RecognitionInternational