Vol. 69.] THE HAFSLO LAKE A> T D THE SOLVORN VALLEY. 19 



2. On the Hafslo Lake and the Solvokn Valley (Norway). By 

 Horace Woollaston Monckton, Treas.L.S., F.G.S. (Read 

 November 20th, 1912.) 



[Plate I.] 



The district dealt with in the present, communication is situated in 

 the North Bergenhus Amt, in Western Norway. It lies north of 

 the main part of the Sogne Fjord and west of its innermost branch, 

 the Lyster Fjord. An account of the locality, under the heading 

 ' Lysterfjorden og Hafslo,' will be found in the admirable paper 

 by Dr. lleusch entitled ' Nogle Bidrag til Forstaaelsen af hvor- 

 ledes Norges dale og fjelde er blevne til,' which is provided with 

 a summary in English. 1 



A geological map of Southern Norway by Dr. K. 0. Bjorlykke 

 will be found in his work ' Det centrale Norges Fjeldbygning ; ' 2 

 and another geological map, on a larger scale, which takes in the 

 present district, has been published by Dr. lleusch. 3 The map 

 which I give (fig. 1, p. 20) is merely a sketch-map, founded on the 

 Topographical Map of Norway, Sheet 29 B (Sogndal), with tho 

 geology sketched in from the above-mentioned geological maps. 



If we look at Dr. Bjorlykke's map, we shall see a great mass of 

 igneous rock marked at the head of the Sogne Fjord with a diagonal 

 boundary running north-east and south-west. Along this boundary 

 there is a narrow belt of Silurian and associated strata, dividing 

 the igneous rock from a vast area of Archaean gneiss, etc., which 

 extends outwards from it to the western coast. On the Archrean 

 . area is a great plateau covered with perpetual snow, Jostedalsbraeen, 

 associated with many smaller snow-covered plateaux; and they 

 have also a north-eastern and south-western trend, parallel with 

 the Silurian belt at a distance of some 18 miles. 



On the south-eastern side of the snowfields we find a series 

 of valleys with a tendency to run in a south-easterly direction 

 at right angles to the Silurian belt. They are Morkereidsdal, 

 Jostedal, the valley of the Vejtestrands Lake, and Sogndal. Then 

 we find other valleys running at right angles to the above, and 

 parallel with the Silurian belt : they are the upper part of the 

 Lyster Fjord and the Sogndals Fjord with its allies. 



The Hafslo Lake at once impresses one as being of interest, for 

 it is placed at a point where two of these lines intersect, and I will 

 briefly trace the course of its drainage-line from the snowfield ; 

 but first I would remark that the valleys in question are, in fact, 



■ x Norges Geo]. TJndersok. No. 32 (1901) pp. 12i & 146-152. 

 2 Ibid. No. 39 (1905). 3 Ibid. No. 47 (1908). 



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