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glacier, and in the valleys of the larger glacieis which come 

 down to Yakutat bay. The moraine terraces — the hum- 

 mocky moraine which forms the southeastern margin of 

 Yakutat bay, as far out as the village of Yakutat, the 

 similar moraine about the head of Russell fiord and the 

 crescentic deposit which extends as a submarine ridge 

 across the mouth of Yakutat bay — descend in the direction 

 of the ocean, and are evidently of former glacier expansion. 

 From these four lines of evidence it has been concluded 

 that at the period of the greatest expansion, all the glaciers 

 were much larger than now. Malaspina glacier then rose 

 much higher on the slopes of the mountains west of Yakutat 

 bay, its tributaries were greater, it received tributaries, 

 notably, Lucia and Atrevida, that are now disconnected, 

 and it coalesced with a great glacier that filled Disenchant- 

 ment bay and Yakutat bay out as far as Yakutat village 

 and the submerged moraine that stretches in crescentic 

 form westward to Point Manby. To this expanded glacier 

 that filled Yakutat bay, the name Yakutat Bay glacier has 

 been given; and the similar expanded glacier in Russell 

 fiord has been called Russell fiord glacier. The latter 

 glacier completely filled Russell Fiord and terminated in a 

 piedmont bulb on the inner edge of the foreland, where 

 it has left a crescentic moraine from which outwash gravels 

 slope seawards. 



Second Expansion of Glaciers. 



Since the ancient period of maximum glacier expansion, 

 and far more recently, there has been a second advance, 

 amounting to at least 20 miles (32 km.). The united 

 Hubbard and Turner glaciers, joined by others pushed 

 into Disenchantment bay and southeastward into Russell 

 fiord, while Nunatak glacier, coalesced with Hidden glacier 

 and others and pushed northwestward into the northwest 

 arm of Russell fiord, and southward into the south arm 

 for about two thirds of the way to the head of the bay. 

 During this advance a lake was formed in the southern 

 end of Russell fiord where its shoreline is still visible. This 

 advance of the glacier was of such brief duration and such 

 moderate intensity that the ice erosion did not succeed in 

 removing the gravels previously deposited. Hence it 

 contrasts strikingly with the earlier, prolonged advance 

 by which the bed-rock was scoured out to a depth of many 



