82
Table 2. Definition of the grid system.
Coordinate
Number of nodes
Initial coordinate
Spacing
X
38
1623.6
5
Y
41
1640.2
5
Z
15
71.2
5
Figure 6. Scatter plots of original grades and back-transformed simulated grades.
Table 1. Parameter of the variogram models of each normal score of PC.
Nugget
effect
Spherical
Spherical
Sill
Rotation
Ranges
Sill
Rotation
Ranges
PC1
0.2
0.6
0°/0°/0°
50/100/20
0.2
0°/0°/0°
150/infty/20
PC2
0.3
0.7
0°/0°/0°
70/40/20
PC3
0.3
0.7
130°/30°/0°
55/50/20
PC4
0.4
0.6
130°/10°/0°
70/58/18
PC5
0.4
0.6
0°/0°/0°
70/70/20
PC6
0.4
0.6
0°/0°/0°
120/60/20
Scatterplot of grades
10 20 30 -40 so 80
0
20
40 60 80
I
2
:3
4
I Nickel
o 2 • & a
0
10 20 ~ 40
0 5 10 IS 20 25
scatterplot of back-transformed grades
0
20
40 60
020406080
0 2
4 6 8 10
I backNickel
0 2 4 6 8
12
0 10
30
so
0 10 20 ~ 4(1 50