Palaeozoic Geology of Victoria. 127 



Locality A, 19. — Yellow Water Holes Creek is the position of the 

 long-abandoned '' Good Hope Silver Mine." The shaft here pene- 

 trates calcareous fossiliferous middle Devonian shales. 



Middle Devonian. 

 The Limestone Series. — Very little time was devoted to this 

 series. An important area, however, composed of these rocks, occurs 

 in the northern portion of this region, and is continuous with that 

 in the vicinty of Buchan. The general' features of these rocks have 

 been well described by Howitt (3, 4 and 5), and the age is definitely 

 fixed by the fossils as Middle Devonian. 



Associated with the limestones are calcareous shales, and the- 

 whole series is in general gently folded, though some instances of. 

 high dip are to be noted. Howitt described these limestones as 

 being laid down in troughs and basins in the Snowy Hiver Porphy- 

 ries, into which they have in many cases been further let down by 

 trough faults. General erosion of the present cycle, and probably 

 also that of an earlier period acting unequally on the limestones, 

 and surrounding porphyries has resulted partially in developing 

 important basins, more or less conciding in position with some of 

 those of Palaeozoic times in which the Middle Devonian limestones 

 were laid down. Two basins of these types occur in this region. 

 One is the wide, flat valley of the Ti Tree Creek, surrounded b}- 

 ridges of porphyry and older rocks, save on the northern side, and 

 the other is a narrower valley; to the west, that of the Yellow 

 Water Holes Creek. 



It is interesting to note that small residual Devonian limestone 

 occurrences outcrop in both these valleys partly buried beneath 

 gravels sands and clay of late Kainozoic age. These are represented 

 in Section 9. The trough faulting is assumed as probable from- 

 general considerations. 



It is on the southern end of the large limestone area on a branch, 

 of the Tara Creek, in Mr. A. McRae's property, that the new Com- 

 monwealth Marble Quarry is situated. 



Kainozoic . 

 These deposits are of considerable interest in that they throw 

 some light on physiographical cycles preceding the present one. 

 Their features Avill only be briefly referred to here. They are- 

 broadly divisable into three groups — 



(a) A lower series of marine beds. 



(b) An upper series of fluviatile beds. 



(c) Basalt. 



