[Proc. Roy. Soc. Victokia. 25 (N.S.) Pr. II., 1913.J 



Art. XXV. — General (tad Mining Geologi/ of I he Diamond 



Creek Area. 



Bt NORMAN R. JUNNER, B.Sc. 



(Kcruot Eesearch Scholar, University of Melbourne). 



(With Plates XXV. and XXVI.). 



[Read 12th December, 1912]. 



1. Introduction. 



2. Pi-evious literature. 

 ;}. Physiography. 



4. Stratigi'aphy. 



5. Structural featui-es : — 



(a) Folding-, crvimpled anticlines ; zones of crushing. 



(b) Dip and strike of silurian and evidence of pitch. 



(c) Relation of mining lielts t<) structural features. 



(d) Faulting. 



(e) Igneous intrusions. 

 € Petrology:— 



(a) Silurian st^diments and their origin. 



(b) Basalt series. 



(c) Dykes. 



(d) Discussioii of the alteration of the dykes. 



(e) Gold quartz veins and shale reefs. 



7. Geology of the Diamond Creek mine : — 



(a) Featui'es of the silurian, stru(;tui-.il and lithological. 

 (1)) Breccia and crush conglomerate. 



(c) The Diamond Creek dyke. 



(d) Faulting later than intrusion of the dyke. 



8. Relations of the quartz reefs to one another : — 



(a) Occurrences and relative age. 



(b) Oi'igin <if the vein fissures. 



9. Origin of the gold-bearing solutions. 



10. Occurrence and causes <>f the ore shoots, etc. 



11. Summary and conclusions. 



1. — Introduction. 



The area discussed in this paper comprises the central and 

 western portions of the Parish of Nillunibik. The author originally 

 intended to map the eastern portion also, but oAving to a rather 

 late beginning and' to concentration on the mining geology, this 



13a 



