io6 



FRH)r.|OF NAXSr.N. 



M.-X. Kl. 



ï"'êi- 95- l'i*-' Nazi- (Lindi-snc's). Tlic liylil ol tlu- lif^lithousc is 50.1 metres above sea-level. 



(July 25, 191 I). 



§ 



Fig. 97. Land nortliward Irom I'K'oisund, east ol C hrisliansand. (Sipt. 4, i g 1 1 1. 



islets anrl skerries in some ])laces show inflicalions of two levels of shore- 

 erosion. 



Some observations in the region of Langesund may he of interest 

 to prove the existance of the strandfiat along this coast. 



The low islands in the mouth of Langesund Fjord, when seen from 

 the sea (Fig. 99), exhibit a low level distinctly different from the much 

 higher surface of the mainland on both sides of the fjord. The Langesund 

 Peninsula shows a higher level. 



Fig. 100 represents the southern point of the peninsula on which 

 Langesund is situated. Tliere can be no doubt that the flat points and 

 ledges, a few metres above present sea-level, with the steep cliffs behind, 

 have been cut by shore-erosion. They have obviously the same level as 

 the islets outside, seen in the picture. Tt is hardly probable that these 

 ledges and islets have been formed in postglacial time. We may b? con- 

 vinced of this by looking at the coast on the western side of the peninsula, 

 a view of wdiich is given in Fig. 10 1. The level of these low flat islands 

 with rounded, ice-worn surfaces is approximately the same as that of the 

 flat points and islets of Fig. 100, and it is also the same as the low. flat 

 points forming distinct horizontal incisions in the slopes of the two pro- 

 montories seen behind the low islands in Fig. igt. These formations can- 

 not l)e due to postglacial erosion. 



Hence, we have here a low level or strandfiat along the coast, due to 

 shore-erosion, and distinctly different from the higher general level of the 

 land behind, which is seen as a fairlv even surface on the peninsulas in 

 Fig. loi and also in Fig. 99 on the left hand side. 



The peninsula of Langesund (Fig. 100) is built of sedimentary rocks 

 (phyllite) and so are the low islands and the nearest promontory in 

 Fig. 101, but the distant promontor}- in this picture, which has an 

 especially distinct low point or strandfiat under the steep shore cliif. is 

 built of Archæan rocks. 



Whatever the genetic origin of the higher, fairly level surface of this 

 land may be, there can. in mv opinii^n, be no doubt that the lower level 



