BY T. W. EDGEWORTH DAVID. 659 



A careful examination of the country in the neighbourhood of 

 Barney's Ridge, overlooking Lake Coolamatong, has led me to 

 the conclusion that the lake owes its origin probably to a down- 

 throw fault to the east having a nearly meridional trend. It may 

 be mentioned, too, that recently Mr. W. S. Dun, Palaeontologist to 

 the Geological Department, and University lecturer in Palaeon- 

 tology, has identified specimens of Leptograjytus amongst the 

 Graptolites found at about 2 miles westerly from Berridale. 

 Near Kara Station, about 28 miles from Cooma, there are traces 

 of large river-pebbles marking the former channel of an ancient 

 river, a tributary of the Snowy, or possibly the Snowy River 

 itself. It was pointed out by Mr. Andrews that at the top of 

 the long hill bounding the Snowy valley on the east, at 32 miles 

 from Cooma towards Jindabyne, the small hanging valley, which 

 there descends through a rocky precipitous channel into the broad 

 valley of the Snowy, possibly owes its origin to a strong fault 

 throwing down westwards. Certainly the great width of the 

 Snowy valley, between two and three miles at this spot, is a 

 puzzling feature. Below Jindabyne the valley is narrowed in by 

 rocky rounded foot-hills through which the Snowy River has cut 

 a zigzag gorge with overlapping rocky spurs. The question 

 suggests itself, is this wide flat valley with its rounded rocky 

 foot-hills due to the glaciation accompanied by a Piedmont glacier 

 supplied by cascades of ice formerly pouring over the edges of the 

 Kosciusko plateau in their passage to the east 1 Or is this 

 feature due simply to trough-faulting 1 ? Is the Snowy valley 

 above Jindabyne on the side of a narrow senkungsfeld or trough- 

 fault 1 ? 



It appeared clear to Mr. Andrews and myself that there was 

 a heavy fault bounding the Kosciusko plateau on the south-east, 

 parallel to the channel of the Thredbo or Crackenback River. 

 The throw of this fault appears to increase towards the north- 

 east, lessening, however, and possibly dying out altogether in a 

 south-westerly direction. We also obtained evidences of probably 

 more than one cross-fault running almost at right angles to the 

 direction of the main fault. One of the most noticeable of these 



