Page 92 - Introduction to Mineral Exploration

5: FROM PROSPECT TO PREFEASIBILITY 75
Vein strike and dip
PLAN OF LEVELS ONE AND TWO, NORTH LODE Fractures
GREAT ROCK MINE, DEVON Joint sets
Peg
14 15 16 Shaft
Winze
13
10,020 Survey station
10
Contact between granite
Stope 18 alteration types
Meters 10,010 1 1 55° 12 7 6 19 17 Hematite veins
Adit entrance
8 Gate
9 4 3 1
10,000
21 20 2
5 Cubby
Stope
99,990
99,970 99,980 99,990 10,000 10,010 10,020 10,030 10,040 10,050 10,060 10,070 10,080 10,090
Distance (meters)
1025 LONGITUDINAL SECTION OF
Ventilation LEVELS ONE AND TWO, NORTH LODE
1020 1 shaft 13 14 15 16 GREAT ROCK MINE, DEVON
Meters 1015 Stope 1 12 Peg 0 10m
Traveling
1010
way
Stope
1005
21 10 9 8 7 6 5 19 4 18 17 3 2 1
1000
Winze
FIG. 5.1 Typical underground survey of a small vein mine using tape and compass.

D

C N 1
2
3
4
5
(a) (b)

B
4 5
2 3
E 1 2 3 4 5 1

A′ A (c) (d)
A′ A Closure error
Corrected traverse
0 25m
Uncorrected traverse FIG. 5.3 Sampling strategies across a mineralized
vein. (a) Grab samples across the vein. (b) Channel
samples normal to the vein. (c) Channel samples at
FIG. 5.2 Plot of a typical compass traverse. The the same height above the floor. (d) Channel samples
errors in closure of the traverse can be corrected at the same height but with individual samples
using the calculations shown in Table 5.1. (Modified oriented normal to the strike of the vein. In all cases
from Reedman 1979.) the vein is shown in vertical section.