Currently, in financing cases concerning state-run mineral resources base reproduction, especially in terms of identifying forecast resources, and in some cases regarding the category of reserves C2, there is an urgent need to develop ranking techniques for subsurface allotments according to their prospects. In such situations, the use of fuzzy logic models will allow formalizing and automating integral estimation calculation of subsurface allotments for the purposes of their ranking. Therefore, the purpose of this work is to develop instructional aspects of ranking subsurface allotments according to prospects based on the use of fuzzy logic. Resulting from the application of this technique it was possible to perform an aggregated assessment of subsurface areas on the territory of the Bryansk region according to geological reports for the period of 2010-2020. The subsurface areas, being subsequently recognized as prospects, were introduced into the model with their expert assessments for this period of work. Thus, we have initiated a methodology for ranking subsurface areas according to their prospects based on the use of fuzzy logic. It provides for the use of the specified production rules to perform the ranking of subsurface allotments taking into account the prospects. Production rules should cover all possible combinations of expert assessments in confidential intervals. Besides, within the implementing techniques it is required to compare subsurface allotments in terms of fuzzy estimates and also clear mathematical sets. This operation is implemented programmatically (Mamdani algorithm) by performing sequential phasificationdefasification operations in the Fuzzy logic component of the Matlab software product.

Estimating the prognostic potential is also based on evaluating the geological potential, taking into account the available geological and economic information on this territory and the existing need for relevant resources. Thus, to make a decision on investing in further exploration on promising subsoil areas, it is necessary to consider a significant number of factors and their corresponding indicators. In such situations, it is customary to use knowledge bases built upon ontological engineering. As a result, it becomes possible to implement the obtained ontological model having a set of geological and economic parameters for estimating expected resources with the integration of the mathematical apparatus of fuzzy logic and set theory. Thus, the authors have considered the methodological aspects of estimating the prospects of the subsoil plots through ontological engineering of geological exploration, taking into account their features, based on using a knowledge base containing a thesaurus of geological and economic indicators by the exploration process stages. The links of geological and economic indicators as part of the subject area thesaurus are determined in order to build an ontological model, which makes it possible to perform factorial economic analysis. The actual evaluation of indicators as part of the thesaurus of the geological and economic assessment of the geological exploration results allows one to characterise the state of the study object and to proceed to estimating the volume of mining commodity output, according to the requirements of the individual territory, region, state (taking into account the volume of exports and imports) of mineral raw materials.