us 



Section C. 



GEOLOGY. 



ADDRESS BY THE PRESIDENT : 



WALTER HOWCHIN, F.G.S. 



Lecturer in Geology and Palceontology, University of Adelaide. 



THE EVOLUTION OF THE PHYSIOGRAPHICAL FEATURES 

 OF SOUTH AUSTRALIA. 



Plates III., IV. 



Muct has been done of recent years in elucidating the chain of 

 events which has led up to the present physiographical contours of the 

 Australian Continent. The new methods of interpreting the existing 

 features of a country and the recognition of their geological significance 

 has opened a new and fruitful field for investigation the importance of 

 which cannot be exaggerated. The American school of geologists led 

 the way into these new avenues of geological observation, while scien- 

 tific workers in other countries have taken full advantage of the new 

 methods. 



The application of the principles of the New Physiography to Aus- 

 trahan land forms has already produced fruitful and revolutionary 

 efiects in the interpretation of surface features. Moxmtain ranges, 

 that had previously been regarded as of very high antiquity, are now 

 known to be of comparatively recent origin ; it has become possible 

 to classify rivers in relation to their respective origins, relative age, 

 and even reconstruct the main outlines of their chequered history. 

 We have learnt to group a large assemblage of data that stand corre- 

 lated in the development and rounding off of a geographical cycle ; 

 and, further, this greater insight into the geological meaning of existing 

 land forms has a retrospective application by which we are better able 

 to understand the fragmentary residues of the geographical cycles of 

 the past. I have only to mention the good work done in this direction 

 by David, Gregory, Andrews, Taylor, Siissmilch, Hedley, and other 

 Australian physiographists as evidence of the great wealth of scientific 

 facts that can be gathered in this new field of investigation. 



