Document Type : Research Paper

Authors

1 Ms Student in mine engineering, faculty of mine engineering University of Tehran

2 Assistant professor of mine engineering, faculty of mine engineering University of Tehran

3 Student of mine engineering Santiago University

Abstract

Due to the costly and time consuming drilling operations andits high risk of mineral exploration, this stage is of great importance.In order to determine optimum drillingpoints, it is essential to prepare a mineral potential map using the Geographic Information System(GIS), to integrate all exploratory factors.Various methods have been developed for preparing the potential mapso far. One of the most effective ones, considering the nature of the geological and mineral phenomena, is the hierarchical method (AHP) in combination with fuzzy logic.In this research, a combined method consisted of hierarchical and fuzzy methods has been used under the name of fuzzy analytic hierarchy (FAHP). In this study, GIS technology has been used as one of the most effective tools for data and exploratory information management for the integration of various data in order to prepare the mineral potential map. In this research, the Naysian Porphyry copper deposit was used as a case study, because this mine, located in Isfahan province on the Uromieh-Dokhtar Volcanic belt of the country, has been under exploratory study, and because of the geological and mineral complexities, the optimal location of drilling sites has a significant sensitivity for detailed studies.The main purpose of this study is to determine the optimum drilling location using FAHP methods. To produce geological, geochemical factor maps, all available data of the Naysian copper deposit have been collected and analyzed. Fuzzy hierarchical process is used to calculate the weight of exploration layers and to implement this precisely, the geological and geochemical experts are used. In the process of integrating the resulting information layers in the GIS, fuzzy operators are used, and to evaluate and validate the obtained mineral potential map, the exploratory boreholes are used. Comparing the generated potential map with the boreholes shows a significant and positive adaptation between suggested drilling locations resulted from this study and the previous drillings. In this regard, the proposed points for the required drilling are provided.

Keywords

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