Document Type : Original Research Paper

Authors

1 Faculty of Engineering, Industrial University of Esfehan, Esfehan, Iran

2 Islamic Azad University, Research and Science campus, Tehran, Iran

3 Industrial University of Esfehan, Esfahan, Iran

4 Research Institute for Earth Sciences, Tehran, Iran

5 Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran

Abstract

Regional exploration of Kahang is located at 73 km of north east of Esfahan city and 10 km of east of Zefreh town. This deposit is located in Uromieh-Dokhtar volcanoplotonic belt. For the first time this deposit was investigated with using the satellite images processing (TM). Base on the primary study, such as field survey, geophysical study, R.S.and petrography and mineralogy investigation the region was founded suitable place for resources of Copper (Cu) and Molybdenum (Mo). Kahang region is an alteration and breccia zone. In generally, more than %99 of rocks of this region are affected by hydrothermal fluids become in the low and high alteration degrees. The rocks of the area include Andesite, porphyritic andesite, Dacite, porphyritic rhyodasite, Diorite, Quartz monzonite and porphyry micro granite. In plutons, from rim to center of massive, is a trend from basic to acid features with less age.  For geochemical surveying, 174 soil samples in systematic method and 143 rock samples of the area have been collected. They are been analyzed for 45 elements using ICP – MS method in Amdel laboratory of Australia. After assurance of accuracy of the results, statistic parameters are calculated. Then correlation coefficient measures of data calculation using two and  multi variables analyze methods. Thus, based on mean measures and standard deviation of normalized data of elements, anomaly of locations is distinguished and they are presented as a table. At this stage for separation and identification of important anomalies using P.N. method. For introducing of the best locations for excavation and also study of geochemical behaviors of Cu and Mo, anomalous maps of 10 elements drown include of Cu, Mo, Au, Ag, Pb, Zn, As, Sb, Mn and Ba. The anomalous maps are drown in first step based on standard normalized duet and percent measures and in the second step with threshold limits plus amounts of standard deviation. Accordingly, it is delineate that the most concentration of hypogenous ores such as Cu and Mo in central part of area in Quartz monzonites and Diorites occurred, whereas the most concentration of supergeous ores such as Pb, Zn and Ag in the rim part of area in andesitic rocks occurred. Finally, for attainment of better results and recognition of anomalies correlated to ores, the composites haloes method is used and the map of composite haloes of supergene and hypogen ores are prepared based on standard normalized data. Solovov method is used for evaluation of erosion surface in ore area. On this base, if the amount of sum of standard normalized data of supergen ore to hypogens ratio is larger than one, we can conclude that the main ore bodies exist in the depth and it conserved from erosion processes. 

Keywords

References
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