GEOGRAPHICAL UNITY OF EASTERN AUSTRALIA. 435 



at least two Post-Tertiary activities resulting in, first, a 

 smooth outer edge for the shelf, and second a rough inshore 

 portion dotted with islands. This double nature of the 

 continental shelf has been pointed out by Hedley. 1 



If now attention be directed to the highlands themselves, 

 it will be seen that in those places where they are most 

 lofty and closest to the coast, there the country breaks 

 down in steps, in senkungsfelder, and in flexures, to the 

 sea. These faults and flexures are frequently arranged 

 parallel to the shore line or continental shelf, and in the 

 south-eastern portion of the continent where the mountain 

 knot occurs at the locality where the highlands turn from 

 east to north, the faults and flexures appear as somewhat 

 parallel curves. Thus the Kosciusko or Muniong Range 

 with its continuation into Victoria as the Bowen Range is 

 one great fault block as is also the line of the Victorian 

 Alps, while Omeo and Lake Omeo appear to occupy a 

 senkungsfeld between these horsts (Fig. 2). The great 

 escarpment on the Big Bogong of New South Wales appears 

 to be a fault along the northern continuation of the 

 Muniong Range. The long and steep scarps of the Wan- 

 derer and Gourock Ranges also represent faulted blocks, 

 as do also the subparallel Oullarin, Cowley and Muniong 

 Ranges. The Snowy River occupies the southern senkungs- 

 feld thus formed, while the Murrumbidgee occupies one of 

 the northern senkungsfelder. 2 Between the Oullarin and 

 Gourock Ranges lies the senkungsfeld containing Lakes 

 George and Bathurst as described by T. G. Taylor. ; 



Braidwood also appears to occupy a senkungsfeld or tilted 

 block bounded by two ranges parallel to coast. Tin* upper 

 Shoalhaven drains the upper portion of these faulted or 



1 Presidential Address, Proc. Linn. Soc, 1900. 



