2 92 LEWIS G. WESTGATE 



to be of topographic importance. The other (Fig. i, 3) is a low 

 ridge nearer the river, apparently connected with a fragment of the 

 upper terrace gravels, and less rugged than the younger drift just 

 north of it. It is not in as marked contrast with the younger drift 

 as the belt of older moraine north of Lake Creek, and there might 

 be some doubt as to its identification. No sections occur, so that 

 one kind of evidence as to its\ge is lacking. 



3. The later moraine. — The later moraine forms a loop about 

 the lower end of Lake Creek, with its higher parts, near the Sawatch 

 Range, rising some 1,000 feet above Lake Creek. Its surface has 

 already been described as more rugged than that of the older moraine, 

 yet it shows typical kettle topography at but one place, where the 

 Hayden road crosses the northkteraL;(Fig. 1,1). The outer slope is 

 the steeper of the two. An interesting^feature of the inner slope of 

 the north moraine is a series of ridgings which remain parallel to the 

 main crest of the moraine for some two miles as it drops to the east, 

 and which seem to represent later stages of accumulation during the 

 beginning of the retreat of the glacier. 



At several points there are sags in the moraine crest, and here the 

 moraine is pushed forward as if tongues of ice had pushed out a short 

 distance beyond the general front of the glacier. The best illustration 

 of this is at the lower end of Lake Creek, where the main morainic 

 ridge is breached, and a small moraine pushes out through the breach 

 nearly to the Arkansas River. The contrast is especially noticeable 

 on the north, where the two make a sharp angle with each other. A 

 second illustration occurs on the north lateral, where it is crossed 

 by the Hayden road, and again on the south lateral between the two 

 areas of older drift. 



Moraines of recession occur along the course of Lake Creek. 

 The first of these is just below the lower lake — a belt of low morainic 

 knolls which swings around and unites with the inner side of the 

 main moraine. This moraine of recession can be traced to its union 

 with the main moraine, but it cannot be separated from the main 

 moraine thereafter. A second low recessional moraine swings in a 

 semi-circle across the valley at Interlaken, separating the two Twin 

 Lakes from each other. This has its wash-plain, and merges with 

 the larger moraine, though it can be followed back as a distinct ridge 



