The edge effect in geostatistical simulations

Abstract

The problem of edge effects in sequential simulation is widely acknowledged but usually overlooked in geostatistical simulations. They can, however, have significant effects on simulations, especially for situations in which the variogram range is relatively large compared to the size of the simulation area (volume). Failure to account properly for the issue can bias simulations by generating values with ranges of correlation and statistical characteristics that differ from those specified. In this paper, we investigate edge effects in detail using sequential Gaussian simulations and derive the critical threshold at which an edge effect becomes significant. Edge correction techniques, such as guard areas, are discussed as a means of mitigating the effects.