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Fractal methods are regarded as a highly efficient method for more accurate separation of boundaries between mineralized zone in shallow and deep studies. In this research, concentration-number (C-N) and concentration-area (C-A) fractal methods were used in order to identify promising areas of the elements like Cr, Co and Ni in the Khoy 1:100.000 geological mapping sheet, NW Iran. The factor analysis was performed on the elements, and factors, which were related to the elements, were isolated and studied by both fractal methods. The current geological locations of the extreme anomalies were investigated and the results showed a very close relationship and overlapping. The results of the presented models show that the most elements under study are located in the central and southwestern parts of the sheet. From the point of view of the lithology, these areas correspond to the serpentinite ultramafic units of harzburgite and dunite, and as a result, there is a high probability of Cr mineralization. The achieved results are confirmed by factor analysis. This means that a factor accumulation of these elements is exactly the same as those of each element.

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Farsesh barite in the central part of Iranian SanandajSirjan zone is a sample of epigenetic hydrothermal mineralization in dolomitized limestone, which provides appropriate chemicophysical conditions making the passage of mineralbearing fluids possible. Barite veins may range from a few centimeters to 2 m in thickness that increases downward. The microthermometry measurements obtained from more than 30 fluid inclusions show relative homogenization temperatures ranging from 125 to 200°C with an average of 110°C for Farsesh barite deposits. The mean salinity measured proves 16 times as much as weight percentage of NaCl for barite. Coexistence of liquid-and vapor-rich fluid inclusions in barite minerals may provide an evidence of boiling in ore veins. Moreover, occurrence of bladed calcite, high-grade ore zones, and presence of hydrothermal breccia are all consistent with boiling. Thermometric studies indicate that homogenization temperatures (Th) for primary and pseudosecondary fluid inclusions in barite range from 125 to 200°C with an average of 1,100°C. The δ 34 S values of barite also lie between 8.88 and 16.6 %. The relatively narrow spread in δ 34 S values may suggest uniform environmental conditions throughout the mineralization field. Thus, δ 34 S values are lower than those of contemporaneous seawater, which indicates a contribution of magmatic sulfur to the ore-forming solution. Barite is marked by total amounts of rare Earth elements (REEs) (6.25-17.39 ppm). Moreover, chondrite-normalized REE patterns of barite indicate a fractionation of light REEs (i.e., LREEs) from La to Sm, similar to those for barite from different origins. The La CN /Lu CN ratios and chondrite-normalized REE patterns reveal that barite in Farsesh deposit is enriched in LREEs compared with heavy rare Earth elements (HREEs). Similarity between Ce/La ratios in barite samples and those found in deep-sea barite supports its marine origin. Lanthanum and Gd exhibit positive anomalies, which are common features of chemical marine sediments. Cerium shows a negative anomaly in most samples inherited from the negative Ce anomaly of hydrothermal fluid that is mixed with seawater at barite precipitation. The available data including tectonic setting, host rock characteristics, REE geochemistry, and sulfur isotopic compositions may support a hydrothermal submarine origin for Farsesh barite deposit.

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