PHYSIOGRAPHY OF THE SOUTHERN TABLELAND OF N.S.W. 351 



Murrumbidgee fault escarpment would be the western wall 

 of the valley, the valley itself would be 1,500 feet deep, 

 several miles in width, and with thoroughly mature topo- 

 graphy within its walls. How could this be reconciled 

 with the characters of the valley lower down stream, at 

 Taemas, where, although the rocks out of which it has 

 been cut are soft aud thinly-bedded shales and limestones, 

 it has hardly passed its youthful stage of development ? 

 Near the Bunyan Hill the Murrumbidgee has crossed the 

 Murrumbidgee fault and heads into the Berridale tableland 

 into which it has cut a deep gorge. 



Development of the Upper Murrumbidgee, — That part 

 of the divide separating the Snowy River and Murrumbidgee 

 watersheds, which lies to the south of Oooma, and is called 

 on maps the Main Dividing Range, is very low. Where the 

 road from Oooma to Berridale crosses it, it is really an 

 almost level plain (the Monaro peneplain), and in passing 

 over it one can hardly realize that it is a divide separating 

 two important and extensive drainage areas. Standing on 

 top of the Bunyan Hill near Oooma and looking north along 

 the valley jof the Murrumbidgee in the direction of its 

 present flow, one sees what appears to be a continuous 

 chain of hills standing athwart its course and apparently 

 blocking any possible drainage in that direction. Looking 

 south on the other hand, one sees the Monaro plains stretch- 

 ing west and south, and bounded in the far distance by a 

 low range of hills — the main divide. In this range and 

 due south from the observer, there is a gap many miles 

 in width. No stream flows through this gap — it is a " wind 

 gap." Anyone unfamiliar with the direction of flow of the 

 streams, would from this point of observation, certainly 

 come to the conclusion that all the drainage was flowing 

 to the south and through the above mentioned wind gap. 

 Yet this same gap forms part of the existing divide and 

 through it extends a great plain. 



