Et gneis-amfibolitt-kompleks i grunnfjellet i Valdres. Summary: A complex of gneisses and amphibolites in the archaean of Valdres, Southern Norway.
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- Artikler 
The present paper deals with Archean rocks in the map areas Aurdal and Slidre (see outline map Fig. 1). In Fig. 1 areas covered by Caledonian rocks are left white, (1)=mylonitic gneisses of granitic derivation, (2)=various supracrustal rocks, (4)=gneissic and (5)=a light massive granite, the Flå granite. The object of the present paper is to describe the rocks of division (3) in Fig. 1: a series of rocks ranging from gabbros to quartz diorites and plagioclase granites and metamorphic equivalents. Chemically the rocks are characterized by lime and soda strongly dominating over potash, potash feldspar, thus being absent in most of the rocks. The rocks make up a series characterized by a very high lime-alcali index, amounting to about 240 in the Niggli system. The rock series fits well into the so called PelÅe-Lassen Peak type of Pacific rock series of Burri (1926). Fig. 14 on p. 41 shows a part of Burri's variation diagram with inserted projection points of the three analysed quartzdioritic rocks from the present area. Some of the rocks mapped are massive gabbros and quartz diorites with a mineral development of igneous rocks, but more common are amphibolites and gneisses belonging to a series of mineral facies from amphibolite facies to epidote amphibolite facies with albite as the only plagioclase.