I92I. No. II. THE STRANDFLAT AND ISOSTASV. I4I 



^:^—-d- 



[•svær Plateau to Skjær\-ær and thence seawards. The vertical scale is 5 times exaggerated in relation to 

 Und gives the natural relation of height to length. 



this might be due to the fact that the limestone of Southern Heroi is less 

 resistant to erosion than the harder rocks in the north. 



It is of much interest that real shore formations, striated by later 

 glaciers, were actually observed by Sahlstrom on the surface of this level 

 strandfiat. The lines of demarkation along the foot of the hills rising 

 above the plane of the strandfiat are in some places so sharply defined, 

 that they might be called shore-lines. 



The surface of the many hundreds of very low and flat islands and 

 skerries in the region of Sol vær and Lovunden. north of Donna (see 

 Fig. 114), is obviously at the same low level which v.as measured by 

 Sahlstrom on Donna and Heroi. Pictures illustrating the even flatness 

 of the islands of Solvær and the islands surrounding the solitary mountain 

 of Lovunden are given by Rekstad [1912. Pi. I, Fig. 1], Sahlstrom [1915, 

 Fig. I4J, and the present writer [1904, PI. V, Fig. i\ Rekstad [1915, 

 Pi. II, Fig. i] gives a most illustrative view of the many islands in the 

 region of Heroi, Husvær. and Skålvær (cf. Fig. 113), west of Alsten Is- 

 land with De Syv Sostre (Seven Sisters). It demonstrates the extreme 

 flatness and low altitudes of the many islands in this region. 



There is a striking difference between the low altitudes of these 

 level planes of the emerged strandfiat of Helgeland and the heights, 

 generally stated to be between 30 and 40 metres, of the inner boundary 

 or upper limit of this strandfiat. Sahlstrom could find no traces of this 

 higher level in the region studied by him. He found the plane with a 

 height of about 8 to 10 metres extending to the foot of the mountains. 



J. H. L. ^'ogt [1907, pp. 20 f.j says that, according to his investi- 

 gations along the coasts of Helgeland and the Lofoten Islands, the upper 

 limit of the strandfiat, or the demarkation-line ("Knickpunkt") between 

 its nearly horizontal plane and the steeply ascending mountain-sides stands 

 everywhere at almost exactly the same level. In numerous profiles taken 



