GEOLOGICAL RECONNAISSANCE OF THE STIRLING RANGES. 85 



The Work of Previous Observers. 

 A bibliography is not attempted here, as it is obtainable 

 in Bulletin No. 61 of the Western Australian Geological 

 Survey, p. 203. A summary of previously published obser- 

 vations is given by Maitland 1 and by Jutson. 2 The Stirling 

 Range is also referred to by David. 3 



The principal points to be noted in these descriptions are: 

 A Palaeozoic age has been assumed for the rocks of the 

 area though no fossils have ever been found. 



The metamorphic rocks to the north and south are 

 regarded as older than the sediments of the mountains 

 themselves. 



On the northern side of the range deposits of brown coal 

 have been proved by boring. 



Gregory refers to the Stirling Range as the western end 

 of the southern scarp of the plateau, but, as Jutson points 

 out, the range is in no sense a scarp. Actually the scarp 

 is much further south, beyond the Porongrups. 



Maitland suggests that the Stirling Range is tectonically 

 connected with the Collie senkungsfeld to the west. 



David shows the rocks of the Stirling Range as occupying 

 a trough fault in the older metamorphic series and is 

 inclined to follow Maitland in connecting them structurally 

 with Collie. 



Jutson, after reviewing the various possible explanations 

 of the structure, rejects as improbable either trough faulting 

 or the formation of a horst, and suggests that the hills are 

 due simply to erosion and are of the nature of a monadnock. 



1 Maitland, A. Gibb. — Address on some problems of Western Australian 

 Geology. Pres. Address to the Eoy. Soc. W.A., 11th July, 1916, Perth, 

 1917. 



2 Jutson, J. T. — An outline of the physiographical geology (physio- 

 graphy) of Western Australia. Bull. Geol. Survey, W.A., No. 61, p. 158. 



9 David, T. W. E. — Geology Section, Federal Handbook on Australia. 

 British Association for the Advancement of Science 1914, p. 260. 



