Document Type : Original Research Paper

Authors

1 Department of Mining Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran

2 Geology Department, Science and Research Branch, Islamic Azad University, Tehran, Iran

3 Mining and Metallurgy Faculty, Amirkabir University of Technology, Tehran, Iran

4 Geology Department, Faculty of Basic Science, Tarbiat Modares University, Tehran, Iran

5 WH BryanMining & Geology Research Centre, SMI, the University of Queensland, Brisbane, Australia

Abstract

Determination of different zones in porphyry deposits is on of important goals in their exploration because this operation especially determination supergene zone is important for economical study in these deposits. Traditional methods based on alterations and mineralogical studies are not proper in many cases because these methods are based on petrogaraphical and mineralographical studies, only. Later methods were introduced basis fluid inclusions and isotopes are indirect methods and applied for alterations separation. Fractal methods are applicable in surface geological and geochemical studies for many reasons such as using all data, according to spatial distribution and anomalies geometrical shapes. In this research, concentration-volume method entitled new fractal method is introduced for separation of supergene, hypogene, oxidant and host rock based on major element grade in porphyry deposits. Mathematical base of this method by using of power-law function and partition function for fractal and multifractal modeling, concentration-volume is used for zones separation in Chah-Firuzeh Cu porphyry deposit in Shahrbabak in Kerman province. First, Cu distribution in this deposit was evaluated by geostatistical methods and concentration-volume logarithmic diagram that break points show grade boundaries of different zones and boundary between mineralization and host rock. Also, alteration, mineralogical and zonation models were constructed based on geological observation and compared by results from concentration-volume fractal method. Separated zones by this fractal method are smaller and near to fact and correlated by geological models. Usage of grade parameter that is most important direct and quality parameter constructed reality results.

Keywords

References
 
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