1. A method for creating a heterogeneous earth model (HEM) of a reservoir field, comprising: generating a plurality of wellsite models for a plurality of wellsites of the reservoir field based at least on cluster analysis and cluster tagging performed on log data of the plurality of wellsites; generating a reference model from the plurality of wellsite models, wherein cluster tagging errors of the plurality of wellsite models is minimized to obtain the reference model; constructing a contour plot of the cluster tagging errors on a per-cluster basis in the reservoir field; identifying at least one well location and associated core depth interval based on the contour plot for obtaining additional sampling results; and updating the reference model based on the additional sampling results obtained from the at least one well location and associated core depth interval to create the HEM.