Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/207

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AND CIRQUES IN NORWAY AND GREENLAND.
169

AND CIRQUES IN NORWAY AND GREENLAND.

169

List of Lakes in the fjord-valleys with Terraces and Moraines in

front of thern.

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Names of the lakes.

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kilo-

kilo-

kilo-

met res.

metres.

metres.

metres.

metres.

metres.

metres.

Horningdalsvand ...

7

28

58

54

486

432

71 T.

Bredeimsvand

5

18

23

56

273

217

71 T.

Stryenvand

7-5

16

23

25

198

173

?

Aardalsvand

1-5

10

8

5

186

181

40 T.

Loeu vand

25 2

3 4

115

5

3 11

12

4

13

7

88 90 53 37

133 120 104

90

45 30 51 53

? 136 M.

88 M. 65 M.

Sandvenvand

Houkelivand

Gravensvand

1-8

4

3

29

86

57

41 T.

Oifjordvand

1-8

4

4

17

75

58

107 T.

Vasbygdvand

6

3

2

53

67

14

108 T.

1

1-8

1

3

34

31

24 T.

The question of the manner of formation of these lakes remains. From the numbers above we see that there is a remarkable sym- metry in the occurrence of these lakes. The distance from the sea varies from 1 to 7*5 kilometres ; no lake has a greater height than 90 metres, and they have near their lower end a moraine or a ter- race. The bottoms of all the lakes are lower than the level of the sea. Nine of them can be directly demonstrated to be rock-basins ; near three of them the loose detritus of the terraces conceals the rock in front of the lakes.

Supposing these lakes to have existed before the Glacial epoch, we must assume them to have been accidentally formed symmetrically in all these fjord- valleys by forces for which we cannot account; further, we must assume that the forces which impel glaciers down the valley were in all these places accidentally strong enough to bring the glaciers to the lower end of the lake. But, on the con- trary, by regarding them as having been excavated by the glaciers during the Glacial epoch, we can explain their mode of occurrence and their symmetry. The lakes, that is the rock-basins, end close to the moraines, because the situation of their valleys with regard to the mountain-region supplying the glaciers is a symmetrical one ;