Timing and genetic significance of AMCG suites in the Norwegian Caledonides and their role in defining paleolinks between displaced terranes

Anorthosite-mangerite-charnockite-granite (AMCG) suites are a widespread component of Proterozoic crust. In Norway they are prominently represented in both autochthonous basement units. AMCG suites are formed by complex petrogenetic processes initiated at the crust-mantle boundary and, therefore, they tend to define unique points in time and space, which can then be used for correlating terranes that were disrupted and dispersed during orogenic events. One of these suites is an important component of the Jotun Nappe in Central Norway. Although it is a part of a tectonically very important unit of the Caledonian mountain chain, the age and genesis of these rocks remain poorly understood. The study will establish a complete characterization of the AMCG suite in the Jotun Nappe and evalua te its relationships to metamorphism and deformation events. This will provide a basis for verifying the potential paleolinks with similar units elsewhere in the Caledonides and will help to better constrain the evolution of a very important period in Ear th history. Because it will offer a variety of technically challenging situations the project will also contribute to improve the analytical capability and technical level of the TIMS technique at the laboratory of isotope geology of the University of Oslo.