The implementation of any geostatistical method requires the use of a parametric coordinate system (u v t) such that (u v) corresponds to “horizontal” curvilinear coordinates tangent to the horizons while (t) corresponds to the “vertical” curvilinear axis approximately orthogonal to the horizons. So far common practice consists in covering the geological domain with a “structured stratigraphic grid” and then to use the (i j k) indexes as a sampling of the (u v t) coordinates. In this article we propose a completely different approach based on the recently introduced “GeoChron” model.