61&

60

D (*h*)

(2-29)

as *h*

Therefore, the larger *g *is in relation to *s*, the less

(1) Given a regionalized random variable *Z*(*x*)

correlated nearby observations are. The case when

with a known theoretical variogram, the question

is: how can the value of *Z(x) *be predicted at an

D(*h*)=0 for all *h*>0. In that case, neighboring

arbitrary location, based on measurements taken at

observations are uncorrelated no matter how

other locations? Suppose that *Z *is measured at *n*

closely they are spaced.

specified locations: *Z(x*1), ..., *Z(x*n). For example,

the locations might correspond to *n *preexisting

sill, as in the linear variogram Equation 2-26. In

wells in an aquifer. Let a new location be given by

that case, it is not possible to define a correlation

function as in Equation 2-28. The corresponding

by *x*i=(*u*i,vi). Suppose that, based on prior knowl-

regionalized random variable is said to be intrinsi-

edge of the geology, there are no prevailing trends

cally stationary (Journel and Huijbregts 1978),

in hydraulic conductivity, so the mean of *Z(x) *is

which is more general than covariance stationarity.

assumed to be constant over the entire region:

The theory behind intrinsically stationary vario-

grams will not be presented in this ETL. As long

(2-30)

as a "pseudo-range" *h*max is defined, all of the

(*x*) = (constant)

computations described below can be generalized.

2-9

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