Proterozoic Basement and Scandian Geology of the Outer Trondheimsfjord Region

Abstract

The report is a guidebook for a one day excursion in connection to the COPENA meeting held at NGU 18-22 August 1997. The excursion route is Trondheim- Orkanger-Lensvik-Agdenes-The report is a guidebook for a one day excursion in connection to the COPENA meeting held at NGU 18-22 August 1997. The excursion route is Trondheim- Orkanger-Lensvik-Agdenes-Ørlandet-Hasselvika-Rissa-Rørvik-Trondheim. The purpose of the excursions is to demonstrate lithologies in the Proterozoic basement in the Western Gneiss Region and the Caledonian nappe sequences that are down folded into the basement in thight synclines. The effect of the Scandian deformation and metamorphic overprinting on the Proterozoic gneisses will also be emphasised. The following tectonic units will be studied: Protero- zoic gneisses of the Western Gneiss Region; The Risberget Nappe consisting of augen gneisses; The Sætra Nappe consisting of flagstones; the Blåhø Nappe with mica schist, hornblende schist, amphibolite and marble; The lowgrade Støren Nappe with greenstones, schists, marbles and gabbroic to felsic intrusions: Devonian sediments.