Archean Au-Ag-(W) quartz vein/disseminated ... - Geology Ontario

Figure 35
Figure 36a
Figure 36b
Figure 36c
Geological map of the deepest green carbonate ore stope (4014-63 V2 ) and area
in therootzoneof the green carbonate ore, Kerr Addison mine,showingthecontrol
on deep Au mineralisation by a single, branching and anastamosing "siliceous
break" vein structure (by J.P.S.). This ~2 m wide feeder quartz vein was
photographed at point PI in the diagram (see Figure 62).
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Gear example of folded main stage #4 milky quartz veins in a ductile high
strain zone in green carbonate altered ultramafic material; 3815-73 stope,
3850 ft level. The fact that the main stage veins are deformed indicates that
they formed before the end of ductile deformation (see Figure 32). The exact
location of the photograph (P7) is given on the 3850 ft level plan (Figure 23).
For scale, the rock bolt plate is 10.5 cm square.
Tightly folded main stage (FL#2; Figure 32) quartz vein in flow ore developed
in strained transitional mafic-ultramafic host rocks; 814-61 sill, 850 ft level.
The exact location of the photograph (PI) is shown on the map of the 814-61
sill in Figure 19. The end of the ruler is 20 cm long.
Partially rounded main stage (#4) vein fragments in a post-Au mineralisation,
post-ductile deformation stage #6 fault breccia (see Figure 32 for relative
timing). The fault breccia is ~2 m wide in this location and partly follows an
earlier "siliceous break" structure. 2015-62 East Drift, 2050 ft level. Scale in
cm and inches.
Figure 36d Relatively undeformed, thin quartz vein stringers with marginal pyrite
alteration contrasting with an earlier deformed (folded) thicker main stage
(FL#2; Figure 32) vein, all developed in flow ore; 1117-66 stope, 1000 ft
level. The thicker quartz veins can be dark and smoky. For scale, the rock
bolt plates are 10.5 cm square.
Figure 37 Width histogram of Au-quartz veins, Kerr Addison - Chesterville Au system,
based on measurement of 10,459 individual random drillhole intersections
normal to quartz vein average strike direction. The distribution is logarithmic
with a mean width of 0.62 m. Au-quartz veins measured ranged from ^.3 m
(data truncated at this cut-off) to ~11 m in width. Veins -c0.3 m wide were
observed during mapping to be twice as numerous as those X).3 m.
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