I92I.X0. II. THE STRANDFLAT AND ISOSTASY. 217 



XIV. THE LEVELS OF THE STRANDFLAT AND THEIR 



DEVELOPEMENT. 



We now propose to discuss the possible changes in the level of the 

 shore-line and the relation between the two similar formations, the strand- 

 flat standing- at levels near or slightly above present sea-level, and the 

 much broader continental shelf standing at levels one or two hundred 

 metres below present sea-level. Let us first, however, summarize the 

 conclusions on the nature of the strandfiat to which our investigations 

 have led us. 



Summary of the Results of our Investigations of the Strandflat. 



W'e have found: 



On the one hand that, during the long periods required for the form- 

 ation of the strandflat, the shore-line has maintained very uniform levels 

 along the extensive coasts where a strandflat occurs, /. c. especially in 

 Arctic and Subarctic regions. 



On the other hand that after the formation of the now emerged 

 strandflat began, there has been a negative shift of the shore-line caused 

 either by an upheaval of the coasts or by a lowering of the sea-level. 

 These changes of level have been very uniform over extensive areas. 



On the whole, the strandflat creates the impression of having been 

 formed during long periods when the earth's crust in those regions stood 

 at its natural level of equilil)rium; and since then there has been no ap- 

 preciable tilting of this level on the whole, although there may have been 

 small local changes in the course of time. 



Our investigations show that there are probably several levels of the 

 strandflat: the emerged strandflat has probably in most places two levels, 

 and the submerged strandflat represents at least one level. 



The results of our investigations as regards these levels may be sum- 

 marized as follows: 



The emerged Strandflat. 



Along the west coast of southern Norway, in the regions of Stav- 

 anger, Karmoi, Hardanger Fjord, Sotra, Radoi, Lindås, and Sogne Fjord, 

 the emerged strandflat seems to have two levels: An upper level at be- 



