Summary: SUBDUCTION AND EDUCTION OF CONTINENTAL CRUST; MAJOR MECHANISMS DURING
CONTINENT-CONTINENT COLLISION AND OROGENIC EXTENSIONAL COLLAPSE: A
MODEL BASED ON THE SOUTH NORWEGIAN CALEDONIDES.
Torgeir B. Andersen1
, Bjørn Jamtveit1
, John F, Dewey2
& Eivind Swensson1
1 Department of Geology, University of Oslo, 0316 Blindern, Oslo 3, Norway.
2 Department of Earth Sciences, University of Oxford, Parks Rd. Oxford OX1 3PR, UK.
During continental collision in the
middle Silurian, the thickness of the
lithosphere under the Caledonides of
S. Norway was doubled by
subduction of the western margin of
Baltica, including the Western Gneiss
Region, under Laurentia. Crustal
rocks of the Baltic plate reached sub-
Moho depths of near 100 km or more
as inferred from the presence of coesite