Palaeozoic Geology of Victoria. 



81 



The contact and section generally are important, as they show 

 -clearly that the Serpentine is a pre-Upper Cambrian rock, the denu- 

 <iation of which in part contributed to the Cambrian sediments. 



Map 1. 



Scale 



/ards 



The remaining portion, consisting largely of diabasic pyroclastic 

 material, indicates an Uppex* Cambrian volcanic phase. 



This section shows also an interesting structural twist in the 

 strike, post-Silurian in age, for the whole series, including the 

 enveloping Ordovician and Silurian rocks, are locally bent round 

 from a north-west strike to one varying between 80° and 100°. 

 This continues for more than a mile easterly, the strike then gradu- 

 ally swinging back to a more normal north-west direction. 



Locality (\ (Roan Horse Gully). — A traverse from a few chains 

 on the north side of the Dolodrook, opposite the Roan Horse Gully 

 junction, in a S.S.W. direction, across the Dolodrook, and along 

 the bed of Roan Horse Gully, shows well the relative position of 

 the various rocks, and illustrates the typical structure of the 

 inlier. 



lh,e limestone is again associated with the same basic sediments, 

 which rest against the south side of the Serpentine. The envelop- 



