1 92 1. No. 1 1. 



THE STRANDFLAT AND ISOSTASV 



Fig. 96. Indications of a strandllat outside Spangereid, east of Lindcsnes. Kjeholm in the foreground. 

 To the right the point Kalvchaue on Imsa Island, with a well-marked strandtlat. 'July 25, 191 il. 



Fig. 98. Islands north of the entrance to Kragero. iScpt. 4, igiil. 



of the small islands and the points in this region is a regular strandfiat 

 of the same nature and origin as the strandfiat of the Norwegian west coast 

 where it has, however, a much wider extent. 



It mav be that this low level of the strandfiat along- the southeastern 

 coast of Norway corresponds to the lowest level (12 — 17 metres high) of 

 the strandfiat of the west coast. The reason why it is here so much lower 

 might be, in that case, that this southeastern coast has been less elevated 

 than the west coast after the last development of the strandfiat, because 

 the denudation of this low land, and the amount of waste carried away 

 from it after that time, have been considerably less than what was removed 

 from the much higher and steeper west coast. 



The Inner End of Christiania Fjord. 



As Prof. W. C. Brogger's well known investigations have proved, 

 the Christiania Fjord is a fault trough, in the inner part of which the 

 Silurian or Ordovician clay-slates have sunk down to levels below those 

 of the Archæan region to the east and of the igneous rocks forming the 

 hills to the north and west of the fjord. ]t is to a great extent b\' the 

 subaërial and glacial erosion of these clay-slates, much less resistant than 

 the Archæan and igneous rocks on the sides, that the depression of the 

 fjord has been formed. 



Tf one looks down upon the Christiania valley and the fjorrl from 

 one of the heights round this vallcv, it must strike one that the surface 

 of the many islands in the inner part of the fjord, inside I^ågoi, Lang- 

 åren, and Steilene, and also the peninsulas, Bygdoi, Fornebo, Snaroi, and 

 Konglungen, forms a remarkablv level j^lane. where the ridges generally 

 rise to between 20 and 30 metres above sea-lc\-cl, and very seldom abtn-e 

 40 metres (cf. Fig. 102). 



The lanfl of Archa\'in rocks to the east, i. c. the Nesodd Land and the 

 land east of Runde h'jord. ri.scs abruptlv, Vvith a sharpl\- marked fault 



