CHARACTERIZATION OF INHERENT RANDOM HETEROGENEITY OF WEATHERED GRANITE

Abstract

Soils derived from granitic rocks exhibit a complex degree of variability in space. A grid was
established having 5 m intervals spanning 50 m in length and 20 m in width in order to investigate inherent
random heterogeneity of areas covered with weathered granite. Six major patterns of cone resistance varies
with the depth were identified. Main grid was further divided at selected locations in 1m grids and at one
location in 25 cm grids spanning 1 m in both directions for better understanding of spatial variability at close
proximity. The analyses revealed that the coefficient of variation of cone resistance can be presented as 20%
independent of the depth. Geo-statistics has been shown to be a useful technique in the assessment of
inherent random heterogeneity of weathered granitic profiles. Semi-variogram analyses showed that the
Spherical Models is best fitted to represent the spatial autocorrelation and prediction of cone resistance for
areas covered with weathering remnants of granitic rocks.