The Universal Kriging Mapping of the Neogene EL-markers Rs5 and Δ, Northern Croatia

The area of the Bjelovar Subdepression in Northern Croatia, which represents the southwestern part of Drava’s depression, has been analysed. More than 700 depth data were collected in a regular grid covering the existing structural maps of e-log markers Rs5, Z’ and Δ, with cells 2 x 2 km in size. For zonal assessment, Thiessen polygon method was used as introductory analysis preceding Kriging interpolation on regional scale. The emphasis was on OK and UK interpolation, their comparison and selection of most appropriate method for mapping. Crossvalidation results proved UK technique to be the most appropriate in mapping of e-log markers Rs5 and Δ, thus acquiring the most accurate maps so far of the analysed Neogene area.