Step 1: (Input) 4023 picks of the sub-Cretaceous unconformity were used to identify the extent of the subcropping geological units and delineate the subcrop polygons.
Step 2: (Creating subcrop boundaries) Surfaces for the geological units underlying the sub-Cretaceous unconformity were independently modelled in ArcMap using the ordinary kriging algorithm using picks that were made in unison with unconformity picks. These picks were made to determine the form and geometry of the geological units below the sub-Cretaceous unconformity. These geostatistically modelled surfaces were projected through the modelled sub-Cretaceous unconformity surface to create intersection lines representing the subcrop boundaries. To ensure that the modelled subcrop boundaries were consistent with the eroded unit picks, the results were validated with well control data, and the subcrop lines were adjusted where required.