139 
(Melbournian or older).\ The strata dip 45° to 60° to the west, and 
strike north 22° east up to north 32° east, as showing in the 
ISTo. 9 level. The Templestowe-Diamond Creek anticline passes by 22 
chains to the east of the main shaft, but the dyke and reef would not 
intersect it until well over a depth of 2,000 ft., unless unforeseen faulting 
should carry the fold further to the west at a depth. Several different 
quartz occurrences have been proved in the mine, three of which are— 
(a) I^arrow laminated fault reefs, 3 in. to 6 in. in width, cutting 
the strata. These are, in places, highly auriferous, and 
were formed prior to the bedded veins and dyke reefs. 
They are known as verticals.’’ 
(h) ISTarrow barren bedded quartz veins, laminated and vertically 
slickensided, and with which the slide faults are associated. 
(6') The main auriferous reefs occurring in an extensive dyke 
(propylitic porphyry).^ This class of reef has formed in 
shrinkage fissures on either the footwall or hanging wall side 
of the dyke. 
The dyke strikes on the average north and south, and dips 45° to 
50° to the east. It has intruded along a fault line, the fault breccia 
and conglomerate showing on one or both walls of the dyke, according 
to its direct association with the fault. 
At times the dyke departs from the brecciated area (Fig. 48), and 
blocks of the breccia are now and then included in the dyke itself, show¬ 
ing that the fault and its breccia were formed before the dyke intrusion. 
In width the dyke is from 6 ft. to 30 ft. in places. It is jointed and 
slickensided, especially near the fault slides, which occur on the larger 
quartz-bedded veins and their associated blacF slate. 
These fault slides carry the 
eastern-dipping dyke and reef 
back in a westerly direction (see 
Plate IX.). The different 
strikes of the dyke and the slides 
and their opposite dips give an 
intersection line pitching approxi¬ 
mately north 20°. As the longi¬ 
tudinal and transverse sections 
show (Plate IX.), there are a 
number of these fault slides caus¬ 
ing blanks of varying width. Be¬ 
sides these slide faults several 
cross-course faults have been met 
with in the deeper levels in the 
south workings of the mine. The 
quartz reefs generally occur 
several feet within the dyke, and 
have been more consistently rich 
when about 2 ft. or so away from 
the dyke walls. 
In thickness the quartz is from 
1 in. up to 2 ft., but the average throughout the stoped ground would 
be from 6 in. to 8 in. wide. The payable quartz is always associated 
^ General and Mininff Geology of the Diamond Creek Area, by N. R. Junner, B.Sc., Proc. Roy. Soc. 
Viet., Vol. XXV. (N.S.) pp. 525-553, 1912. 
X50 
Cti 
A. Breccia within dyke. 
B. Breccia away from dyke. 
C. Breccia on dyke wall. 
