The Silvretta nappe

The Silvretta basement nappe belongs to the Upper Austroalpine nappe system, i.e. to the highest tectonic units of the Alps. It comprises approx. 1600 km2 of crystalline rocks which, in the West, are covered by autochthonous Permian volcanic rocks and Triassic sediments. The crystalline rocks of the Silvretta are about one third metabasites (mainly eclogites, amphibolites, metagabbros, -diorites, -tonalites), one third metagranitoids (augengneisses and/or fine-grained leucocratic gneisses) and one third paragneisses (biotite-plagioclase-gneisses, micaschists, feldspar knotted gneisses). Migmatites, marbles, quartzites and calc-silicate rocks are present in subordinate amounts.

We carry out our geologic research in this area of the Grisons by mapping 1:10'000, combined with chemical and isotopic analyses in order to date and to understand the evolution of this part of Switzerland in the last 700 million years.

This site provides a general introduction to the Silvretta and more specific outlines on our papers/abstracts, the PhD Theses, Diploma Theses, Field mappings and the current research projects.