Cole — Glacial Features in Spitsbergen. 201 



that still rise from a floor of rock. A glacier of the ordinary valley-type was 

 visited during our excursions from the head of Advent Bay. It terminates 

 between frost-weathered slopes under the south-east flank of Mount Nor- 

 denskiold. On the surface, above its steep end-wall, the moraine-blocks are 

 so abundant that one may cross the glacier without setting foot on ice. The 

 arctic flora has actually invaded this moraine. A little higher up, the broad 

 surface of the ice is almost free from stones, except for well-marked linear 

 medial moraines. Though the blocks towards the melting ice-front are 

 angular and cannot have travelled very far, it is difficult to believe that they 

 all originated in material above the level of the ice. The crumbling hillsides 

 of Cainozoic and Jurassic strata round about the glacier suggest how a true 

 intraglacial moraine may arise from such rocks as the ice moves down and 

 thrusts itself against and over them. F. Wahnschaffe^ observes that the 

 lower part of this glacier between Mount Nordenskiold and Mount Hierta is 

 " completely filled with coarse stratified detritus." 



The abundance of intraglacial material in the broader glaciers is apparent 

 on their melting margins. The great Nordenskiold Glacier, which enters 

 Billen Bay, may be studied from the raised beaches on which its south side 

 has encroached. A stream arises here along the ice-front, while the more 

 northern portion of the glacier enters the sea, where its margin becomes 

 uplifted by flotation. The part of the ice-front exposed on land is dark with 

 mud and stones, and in places the ice is concealed by a slope of huge boulders, 

 falling over the face and banked up against it (PI. XIII., fig. 10). These 

 boulders are abundant on the surface above ; but they evidently appear there in 

 large part through the melting away of the upper layers of the ice. The 

 numerous blocks of granite, believed to be Archaean, have been derived, accord- 

 ing to De Geer, from masses that are mostly concealed.^ The melting along 

 the glacier-edge must here be slow, and a large amount of material must 

 be carried out into the bay, since no wall-like moraine is beiag constructed. 



Since the ice in Spitsbergen breaks up readily on reaching the sea, 

 " calving " in cascades of ice-blocks rather than in large icebergs, the submarine 

 boulder-clays are no doubt deposited close against the shore. It is ques- 

 tionable if their characters, in that case, are very different from those 

 deposited on land.' Small spiry icebergs arise from the Nordenskiold 

 Glacier, but they do not form a conspicuous feature of the bay. 



' "Die Exkursion des XL. Internationalen Geologen-Kongresaes nacli Spitzbergen," Zeitechr. 

 d. Gesellschaft fiir Erdkuude zu Berlin, 1910, p. 649. 



- This moraine has been studied by E. J. Garwood, " Additional Notes on the Glacial Phenomena 

 of Spitsbergen," Quart. Journ. Geol. Soo. London, vol. Iv. (1899), p. 684. 



' Garwood and Gregory have raised questions as to this point. Op. cit., Quart. Journ. Geol. Soo. 

 London, vol. liv., pp. 210 and 217. 



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