Most of the CAD geomodelers use explicit representation of geological models, such as piecewise linear curves, triangulated surfaces. Another possible approach is an implicit formulation: a function φ is defined overall the domain Ω. The geological features are then the zero level set of the predefined function. Here the basic idea is to approximate the potential function φ by the Euclidean distance in the embedding space, thereby performing all the computations in a Cartesian grid with classical and computationally optimal numerics.