GIS-Based Gold Potential Mapping in the Muteh Deposit Area, Iran, with Respect to a New Mineralization Concept

摘要

The Muteh deposit is a major Iranian gold mine that is located in the Sanadaj-Sirjan metallogenic zone. Gold deposition in Muteh has been previously interpreted to be Precambrian in age, but new studies propose the deposits may be younger and of late Eocene age. Therefore, geologic unit ages of and older than late Eocene are likely exploration targets for gold deposits. The focus of this study is to build a predictive model for mapping gold mineralization in the Muteh region. Based on the new gold mineralization concept in the Muteh deposits, the following conditions appear to be favorable for gold occurrence: (1) proximity to granite/leucogranite intrusive bodies as heat source, (2) presence of hydroxyl alteration minerals, (3) proximity to northeast oriented lineaments/faults, (4) presence of geochemical gold anomalies, (5) co-occurrence of gold pathfinder elements, and (6) presence of heavy mineral signatures. For this study, the potential heat sources were delineated from regional geological maps. The hydroxyl alteration minerals were extracted by applying the Crosta method on ETM+ satellite data, and the fusion of the ETM+ and DEM data was used to interpret structural features. The factor analysis on stream sediment data were utilized to reveal mineralization related geochemical anomalies. Mapping was carried out using a knowledge-based fuzzy logic overlay of evidential maps. Fuzzy scoring was assigned to different classes of evidential maps based on their favor ability in gold potential mapping. The final gold deposition potential map generated from fuzzy integration of geo-exploration dataset suggests 4.4 % of the study area is favorable for gold mineralization. Known gold depositional environments were matched using the fuzzy logic approach, and one new potential gold prospect was identified.