Utilização de elipsoide de anisotropia variográfica como indicador cinemático em maciços rochosos fragmentados por falhas - o exemplo do depósito de asbestos crisotila cana brava (Minaçu, GO)

Abstract

The parameters of a variogram depend on which direction it is calculated, such as the ellipsoid of variographic anisotropy, whose axes indicate the directions of higher, medium and lower continuity of the variable used to calculate the variogram. Consequently, the ellipsoid can be used as a kinematic indicator, since the anisotropy ellipsoids of blocks of the same rock massif or mineralized body will be rotated if the blocks are also rotated. The chrysotile ore body of the Cana Brava Asbestos deposit is composed of 13 blocks separated by faults. Comparing the ellipsoids of variographic anisotropy of the variable amount of chrysotile in these 13 blocks, it was observed that, although they are displaced in relation to each other, in most cases this displacement was not caused by rotation. As a result, it was possible to group some blocks together and use only six ellipsoids and their respective variograms to estimate the amount of chrysotile in the deposit.