1921. No. 1 1. 



THK STRAXDFLAT AND ISOSTASY. 



103 



Fig. 913. \'ic\v south-westwards towards Sogndal and the moiilh of Josing Fjord, troni a hill I135 nn'tres) on 

 the peninsula north of Presteskjær Lighthouse. (Sept. 30, igri). 



paratively narrow, hut low and well marked .strandfiat, cut in solid rock, 

 between the .shore and the fairlv steeply rising hills. This strandfiat may 

 he a couple of kilometres broad, with a level perhaps about 20 metres or 

 less above the sea. It extends along the coast southeastwards as far as 

 Egeroi, on the western peninsula of which it is fairly well developed. 

 But further southeastwards from this island the coast becomes high and 

 often precipitous as far as Lister, and there are only few indications of 

 a very narrow strandfiat in front of the steep mountain slope along this 

 coast. 



The sivdden change in the character of the coast is obviously due to 

 the difference in geological structure, the coast in this region being built 

 up of resistant igneous rocks, the so-called Egersund labradorite rocks 

 [Kolderup, 1914]. This high coastland is dissected bv narrow vallevs, but' 

 its general surface is fairly level or undulating, rising gently inland from 

 a fairly equal height of about 130 to 150 metres, above the sea, near the 

 coast. Tt is j)robably the same kind of formation as the fairly level coast- 

 land of southern Norwav, about 100 metres high or somewhat more, 

 which Ahlmann calls the base-levelled plain of southern Norway. I think 

 it represents more or less the Palæic mountain surface of this region 

 which has not been substantially lowered bv glacial erosion because the 

 inland-ice has had very slow movements over these mountain plateaus, 

 although the rocks have everywhere 1 een rounded b\- the moving ice (see 

 Fig. 91). 



In the .region northwest of Presteski;cr Lighthouse I found, by baro- 

 metric reading, the fairly level mountain surface (Fig. 91) to be between 

 140 and 180 metres above the sea, and to the southeast, in the region of 

 vSogndal and losing Fjord (Fig. 92), it was ])erhaps about 170 to 200 

 metres liigh, with a steep declivity down to the shore, where in several 

 places, under the headlands and elsewliere, there are ledges cut in the 



