161 
displacement had not been quite so great as it is, 8 feet of washdirt 
might be drilled through before bedrock was reached, although only 4 feet 
of washdirt actually exists. On the other hand, if there had been a down¬ 
throw above the fault, a hole could be drilled to bedrock without touching 
washdirt, although there would be 4 feet of rich washdirt, perhaps, 
within a few inches of the bore. The anomalies that frequently occur in 
boring for these tertiary leads are, no doubt, largely attributable to earth 
movements of a similar nature. 
In the neighbourhood of this mine volcanic activity on a vast scale took 
place subsequently to the laying down of the rich gold-bearing gravels, 
and enormous quantities of rock material were ejected and poured out from 
the craters, the principal of which was Moorokyle, which is near to this 
mine. The subsidences and faults may have been caused through the 
rocks settling down into the cavities from which the volcanic material now 
at the surface was derived. 
The Spring Hill and Gentral Leads Mine. 
In the workings of the Spring Hill and Central Leads Mine there is a 
remarkable occurrence of volcanic ash and lava associated with washdirt- 
From the sections obtained (Figs. 27, 28), it appears that auriferous 
; . , ' * £/ 7 /£ Cfi/M 7 - .’ • - 
Qt/AXTZ S0(/l£££ 
/ , 3:-x2'0"x3'6" 
<=> Ai/x/rmffs mvr h/ashd/rt. 
O,~~ -- - - c? 
SAM £ ASH 
BASALT 4" 
AUR/rsROi/s wASH-mr 
_ O O 
n^nrrTTTTTy 
'sorr crby SLArtj 
. t '(P/Pf CiAY) / 
Figure No. 27. 
Sketch Section No. 2 Balance Shaft, 750 ft. N.W. of No. 3 Rise, Spring Hill 
and Central Mine. East side of level. Scale, 4 ft. to i in. 
3 '0 
vVV;-.. CM/Sl ’ • • • ' 
(mao ms ); \ 
4 » 
/' 0 " <=> 
0 CO <=> <=> o 
_C2> o O <-•> o 
e 
LliiCi *1 I 
0 _^ -Fa “——— 
mSJS-D/RY, 3U/R/f£/?OOS 
££S/Cl/LAP 8AS/U 7 
''WlmMEfflWlp/lli 
Figure No. 28. 
wASH-o/xr, 
Sketch Section. Same Site as Figure No. 26, but on- west side of level. 
