Fra det nordøstlige af Jotunfjeldene

Abstract

Forkortet: This mountain region forms the highest part of Southern Norway between latitudes 61\u00B0 28' and 61\u00B0 46' N. The two highest mountains in Norway, Gald- høpiggen and Glittertinden, lie within the territory. The rocks belong to three divisions. 1. Gabbro with numerous bosses of peridotites. 2. Gneiss and quartz-schists. 3. Phyllites with some strata of crystalline limestone. The gabbro embraces the greater part of the territory. The rock is granular- crystalline rock and consists of plagioclase (andesine and labradorite), dial- lage and frequently also of hypersthene and hornblende. As accessory minerals occur biotite, olivine, orthoclase, quartz, magnetite, apatite, garnet and zircon. Sheets of rocks in which the feldspar mostly consists of microproper- thite (confer fig.1 pl.I) are found in some localities within the gabbro region Many bosses of peridotites which have been differentiated out from the magma of the gabbro are also met with. The massive rocks in this region have frequently been compressed, so that foliation has often been superinduced upon them. Below the gabbro-rocks is everywhere found Gneiss-quartzite schists.