214 Carl Fred. Kolderup. [Ni 



Summary, 



The Geology of the District of the Bergen Arches. 



(Pages 9—14.) 



The tract of land shown on the map (fig - . 1) is distinguished by 

 a strikingly curved arrangement of its rock-zones. I have given it 

 the name of the Bergen district or the district of the Bergen arches. 

 The whole complex is, as may be seen, curved round the peninsula 

 of Lyderhorn situated to the southwest of Bergen. The islands to 

 the west and the mainland to the east are partly separated from 

 the Bergen arches by faults. 



The present map is based on the geological rectangular maps 

 of the districts of Bergen and Haus published in 1880 by the Geo- 

 logical Survey of Norway, and the maps of Sartor and Herlo 

 published i 1901 by the same institution, whose director, Dr. Reusch, 

 Avrote the accompanying text. By numerous excursions in the Ber- 

 gen district, I have been able to correct several errors in the old 

 maps of the Bergen and Haus districts, and my conception of the 

 relations of the rock-zones differs on several points from the former 

 vie ws. 



The Archæan Rocks. 



The Archæan rocks to the west and the east are not shaded 

 on the map. The main rock is gneiss. In the north-eastern part 

 it consists of a comparatively homogeneous grey gneiss, giving in 

 some places a very massive impression. South of Vaksdal zones 

 of gneiss alternate with zones of phyllites. As for the gneisses 

 in the islands of Havgaren or Øigaren, west of the Bergen arches, 

 I can characterise them briefly by citing a few quite short extracts 

 from Dr. Reusch's description of „Skjærgaarden ved Bergen". ''The 

 Archæan gneiss in the islands of Havgaren and in the northern quarter 

 of Sotra is, on the whole, quite homogeneous, light-coloured, and 

 not micaceous. In sections cutting the stretching-direction the rock 

 has a rather massive appearance; micaceous strata are seen only 



