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Practical Geostatistics 2000

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Symbols used in the Text

 

h,d,b,l        distances or lengths

g(h)            semi-variogram between two points---theoretical model

g l(h)          semi-variogram between two cores along the same borehole---model

g*(h)           experimental point semi-variogram

g l*(h)         experimental core semi-variogram

g(l;b)          semi-variogram between two parallel cores

c(l)             semi-variogram between a point and a line

c(l;b)         semi-variogram between a line and a panel

H(l,b)         semi-variogram between a point and a panel

F(l)            variance of grades within a line

F(l,b)         variance of grades within a panel

F(l,b,d)      variance of grades within a block

              average value of the semi-variogram between two specified ‘areas'

a                range of influence of a semi-variogram

C               sill of a semi-variogram

C0              nugget effect

p                slope of the linear semi-variogram

a                           parameter in generalised linear and de Wijsian semi-variograms

g                grade (value)

s                 standard deviation of the grades

                mean value of the grades

y                logarithm of the grade

y                mean value of the logarithm of the grade

sy                standard deviation of the logarithm of the grade

z                 Standard Normal deviate

f(z)            height of the Standard Normal probability density function

F(z)           probability that a Standard Normal variate is less than z 

c                cutoff value, selection criterion

c               average grade above cutoff

P                proportion of the ore which is above cutoff

A                ‘area' to be estimated

T                unknown grade of area to be estimated

S                sample set available for estimation

T*               estimator formed from the sample values

wi               weight accorded to sample @i@

se               standard error of a linear estimator

se               standard error of the arithmetic mean of the samples

sk               standard error of kriging estimate

dq, dh        a small angle, a small distance