Detection of rare earth element anomalies in Esfordi phosphate deposit of Central Iran, using geostatistical-fractal simulation

Document Type : Research Paper


1 Department of Earth Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Department of Geology, North Tehran Branch, Islamic Azad University, Tehran, Iran

3 Department of Petroleum and Mining Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran

4 Department of Chemistry, North Tehran Branch, Islamic Azad University, Tehran, Iran


This study is aimed to determine geochemical anomalies of rare earth elements (REEs) and provides a concentration distribution map for the Esfordi phosphate deposit (EPD), Bafq metallogenic province (BMP), Central Iran. With an average grade of 5519 ppm for REEs, the EPD is one of the prominent deposits of the region. In this research, sequential Gaussian simulation (SGS) and concentration-area (C-A) fractal modeling are used to determine concentration anomalies and provide a ∑REEs concentration map based on surface data. The log-ratio matrix is used to investigate the mineralization processes, determining the relationships between the anomalies and the rock units, and validating the results of SGS fractal modeling. The results are indicating that the main anomaly has strong correlation with the apatite-iron, and in particular, with the apatite mineralization, which can be considered as an exploration guide. The results also confirm the efficiency of simultaneous application of fractal modeling and SGS simulation.


Article Title [فارسی]


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