“…in which the semivariance and N(h) are the number of pairs of the measured values Z(x i ) and Z(x i +h), separated by an h vector. From the experimental semivariograms, 11 theoretical models of semivariograms, Circular, Spherical, Tetraspherical, Pentaspherical, Exponential, Gaussian, Rational quadratic, Hole effect, K-Bessel, J-Bessel and Stable, were adjusted according to Johnson et al (2001) and Pasini et al (2014). By using the algorithm of weighted least squares, these models were adjusted to the experimental semivariogram, and the model parameters were defined: nugget effect (C 0 ), sill (C 0 +C 1 ), and range (a).…”