Yol. 50.] GOSA.U BEDS OF THE GOSAU DISTRICT. 123 



§ 3. Situation and Physical Aspects of the Gosau Valley. 



The Gosau Valley is situated in the south of Upper Austria, close 

 to the borders of Styria, and in the heart of the Salzkammergut. 

 It forms almost a complete semicircle to the west and south-west of 

 the Lake of Hallstatt. 



The waters of the Gosau Bach have their origin in the glacier-fed 

 streams of the western slopes of the Dachstein, which rises to a height 

 of over 10,000 feet above the sea-level. These streams plunge into 

 the Hinterer Gosau See, a small lake about k mile long, and thence 

 descend somewhat steeply to the Vorderer Gosau See, in a north- 

 westerly direction, receiving on their way the mountain-torrents of 

 the Dounerkogl. From the foot of this lake, which is about 1 mile 

 long and \ mile broad, the stream keeps a general northerly course, 

 sometimes trending slightly to the east, until it reaches Gosau 

 village, about 5 miles from the Yorderer See, when it gradually 

 sweeps round to the east, and maintains this course down the narrow 

 gorge of the Gosauzwang until it finally mingles with the waters of 

 Hallstatt Lake at Gosau Miihle. 



The Gosauthal proper consists of that broad, open, cultivated, 

 portion in which the village of Gosau lies, and which extends 

 approximately from Gosau Schmidt on the south to Klaushof, a 

 couple of miles or so E.jST.E. of Gosau village. The whole of this 

 valley thus forms one of the main lines of drainage on the northern 

 slopes of the Dachstein massif : another well-marked line of drainage 

 being formed by the "Wald Bach, which flows E.IS".E. from the 

 Hallstatt glacier. 



It is not difficult to see that the physical characteristics of this 

 valley are due to its peculiar geological structure. Thus the steeper 

 and bolder portions, both in the neighbourhood of the Gosau lakes 

 and in the Gosauzwang, consist of hard, compact, crystalline lime- 

 stones, much folded and disturbed, belonging to the Upper Triassic 

 Dachsteinkalk and Wettersteinkalk, the latter of which constitutes 

 the jagged chain of peaks of the Donnerkogl, reminding one of the 

 dolomite mountains of the Tyrol ; while the former builds up the 

 greater part of the Dachstein group and most of the higher mountains 

 round the Lake of Hallstatt. But in that portion of the valley which 

 constitutes the Gosauthal proper there is a broad, more or less 

 basin-shaped, depression in the Alpine limestone. It is in this that 

 we find the considerably younger and less disturbed Gosau Beds ; and, 

 as one would expect, they consist of much softer material, chiefly thick 

 beds of marl, alternating with sandstones, shales, and conglomerates. 

 Hence the decreased height and gentler slope of the flanking moun- 

 tains, the broad pasture-lands and generally tamer aspect of the 

 valley. 



II. Distribution of the Beds : Stratigraphy of the Gosau 

 District, and Comparison with other Areas. 



The Gosau Beds, while they may be said to be typically developed 

 in the Gosau Yalley, have on the whole a fairly extensive distribu- 



k2 



