28 T. W. E. DAVID. 



Mount Stavely Range. This geosyncline between Benambra 

 and the Glenelg River is warped across in a direction trend- 

 ing from about N. and S., or a little E. of N. and W. of S. 

 by ancient axes or hinges of folding referred to by Professor 

 Gregory as the line of the Oolbinabbin Range. 1 



On the latest geological survey map of Victoria this area 

 is coloured 4 Heatlicotian,' and referred with a query to 

 the Cambrian. Sections across this supposed Cambrian 

 axis have been published by Professor Gregory. 2 In section 

 7 (op. cit.) he shows a parallel axis to the Oolbinabbin axis 

 at Dookie. On the other hand Professor Skeats in his able 

 and well illustrated paper marks with a query as basal 

 Ordovician the diabase series of the Knowsley district N. 

 of Heathcote. In any case all the Victorian geologists 

 seem agreed that there is an old axial line of folding run- 

 ning approximately meridionally through Heathcote. 



On either side of this Oolbinabbin axis lie troughs of 

 Ordovician rocks. These have been folded very strongly 

 as shown by Mr. E. J. Dunn, 3 on lines about N. 25° W. (true) 

 and E. of S. The folds near Bendigo (Sandhurst) are some- 

 what asymmetrical, the source of the thrust being to the E., 

 so that the folds are overturned towards the W. So much 

 have these Ordovician strata been compressed that for 

 considerable distances they now occupy only one half of 

 their original dimensions measured along E. and W. direc- 

 tions. Professor Gregory shows four troughs of Silurian 

 rocks 4 infolded in the eastern Ordovician syncline between 

 Keilor and Mount Wellington. A glance at the geological 

 map of Victoria shows that the Snowy River porphyries of 

 Lower Devonian (?) time were developed along a line of 

 eruption approximately meridional, and the middle Devonian 



1 The Geography of Victoria, p. 69, 70. 



* Proc. Boy. Soc. Victoria, 1902, pi. xxv. 



3 Report on the Bendigo Goldfield. By authority, Melbourne, 1896. 



* Proc. Roy. Soc. Vict., 1902, pi. xxv, section 5. 



