HYDRO-GEN - A SPATIALLY DISTRIBUTED RANDOM-FIELD GENERATOR FOR CORRELATED PROPERTIES

This paper describes a new method for generating spatially-correlated random fields. Such fields are often encountered in hydrology and hydr ogeology and in the earth sciences. The method is based on two observa tions: (i) spatially distributed attributes usually display a stationa ry correlation structure, and (ii) the screening effect of measurement s leads to the sufficiency of a small search neighborhood when it come s to projecting measurements and data in space. The algorithm which wa s developed based on these principles is called HYDRO_GEN, and its fea tures and properties are discussed in depth. HYDRO_GEN is found to be accurate and extremely fast. It is also versatile: it can simulate fie lds of different nature, starting from weakly stationary fields with a prescribed covariance and ending with fractal fields. The simulated f ields can display statistical isotropy or anisotropy.