Document Type : Original Research Paper


Department of Geology, Payame Noor University, Tehran, Iran


The purpose for this research is to define the gold mineralization potentials by the concentration-number fractal and staged factor analysis modeling based on rock samples at the Bardaskan area (NE Iran). Two main gold mineralization types are epithermal and disseminated systems in this district. First, the staged factor analysis is carried out at four stages. The stepwise factor analysis was applied in three stages to remove noise elements. Moreover, staged factor analysis was applied in the fourth step based on metallic elements including Au, Ag, Cu, As, Fe, Mo, Bi, La, S, Zn, and Cd were grouped. These elements are grouped at four factors, and related factors for gold mineralization are F1-4 (first factor in the fourth stage) which is consisting of As, Mo, S and Fe and F3-4 (third factor in the fourth stage) includes Au and Ag. The concentration-number log–log plots for factor scores of F1-4 and F3-4 were generated, and their threshold values were calculated to create the factor score’s geochemical maps. Based on these results, the gold mineralization potentials are positioned in the NE, northern and SE sections of the district, which indicate a correlation among alteration zones, including chloritization, sericitization, and silicification alteration zones and faults and fault’s intersections. Main Au mineralization occurred in silicified-sulfidic veins/veinlets in NE and northern portions of the region. However, high grade F3-4 anomalies are located in intersection of faults and neighboring fault zones especially at the northern part of this district. Moreover, Samples with Au≥ 100 ppb were situated in major anomalous parts of F3-4 (Au-Ag) and marginal parts of the F1-4, which include pathfinder of gold mineralization.


[1]. Yousefi, M., Carranza, E.J.M., Kreuzer, O.P., Nykänen, V., Hronsky, J.M.A. (2021). Data analysis methods for prospectivity modelling as applied to mineral exploration targeting: State-of-the-art and outlook. Journal of Geochemical Exploration 229, 106839.
[2]. Yousefi, M., Kreuzer, O.P., Nykänen, V., Hronsky, J.M.A. (2019). Exploration information systems – A proposal for the future use of GIS in mineral exploration targeting. Ore Geology Reviews 111, 103005.
[3]. Daneshvar Saein, L., Rasa, I., Rashidnejad Omran, N., Moarefvand, P., Afzal, P. (2014). Application of number-size (N-S) fractal model to quantify of the vertical distributions of Cu and Mo in Nowchun porphyry deposit (Kerman, SE Iran), Archives of Mining Sciences. 58 (1): 89–105.
[4]. Afzal, P., Yasrebi, A.B., Daneshvar Saein, L., Panahi, S. (2017). Prospecting of Ni mineralization based on geochemical exploration in Iran. Journal of Geochemical Exploration 181, 294-304.
[5]. Nazarpour, A., 2018. Application of C-A fractal model and exploratory data analysis (EDA) to delineate geochemical anomalies in the: Takab 1:25,000 geochemical sheet, NW Iran. Journal of Earth Sciences, 10, 173-180.
[6]. Pourgholam, M.M., Afzal, P., Yasrebi, A.B., Gholinejad, M., Wetherelt, A. (2021). Detection of geochemical anomalies using a fractal-wavelet model in Ipack area, Central Iran. Journal of Geochemical Exploration 220, 106675.
[7]. Shahbazi, S., Ghaderi, M., Afzal, P. (2021). Prognosis of gold mineralization phases by multifractal modeling in the Zehabad epithermal deposit, NW Iran. Iranian Journal of Earth Sciences 13, 31-40.
[8]. Davis, J.C. (2002). Statistics and data analysis in Geology (3th ed.), John Wiley & Sons Inc., New York, p. 342-353.
[9]. Afzal, P., Mirzaei, M., Yousefi, M., Adib, A., Khalajmasoumi, M., Zia Zarifi, A., Foster, P., Yasrebi, A.B. (2016). Delineation of geochemical anomalies based on stream sediment data utilizing fractal modeling and staged factor analysis. Journal of African Earth Sciences 119, 139-149.
[10]. Zuo, R., Agterberg, F.P., Cheng, Q., Yao, L. (2009). Fractal characterization of the spatial distribution of geological point processes. International Journal of Applied Earth Observation and Geoinformation. 11 (6): 394-402.
[11]. Daneshvar-Saein, L. (2017). Delineation of enriched zones of Mo, Cu and Re by concentration-volume fractal model in Nowchun Mo-Cu porphyry deposit, SE Iran. Iran Journl Earth Sciences, 9, 64-72.
[12]. Jebeli, M., Afzal, P., Pourkermani, M., Jafarirad, A.R. (2018). Correlation between rock types and copper mineralization using fractal modeling in Kushk-e-Bahram deposit, Central Iran. Geopersia Journal 8 (1), 131-141.
[13]. Saadati, H., Afzal, P., Torshian, H., Solgi, A. (2020). Geochemical exploration for Li using Geochemical Mapping Prospectivity Index (GMPI), fractal and Stage Factor Analysis (SFA) in NE Iran. Geochemistry: Exploration, Environment, Analysis 20, 461-472.
[14]. Malaekeh, A., Ghasemi, M.R., Afzal, P., Solgi, A. (2021). Fractal modeling and relationship between thrust faults and carbonate-hosted Pb-Zn mineralization in Alborz Mountains, Northern Iran. Geochemistry, 125803.
[15] Shamseddin Meigooni, M., Lotfi, M., Afzal, P., Nezafati, N., Kargar Razi, M. (2021). Application of multivariate geostatistical simulation and fractal analysis for detection of rare earth elements (REEs) geochemical anomalies in Esfordi phosphate mine, Central Iran. Geochemistry: Exploration, Environment, Analysis21, geochem2020-035, 1-17,
[16]. Yousefi M., Kamkar-Rouhani A., Carranza, E.J.M. (2012). Geochemical mineralization probability index (GMPI): a new approach to generate enhanced stream sediment geochemical evidential map for increasing probability of success in mineral potential mapping. Journal of Geochemical Exploration, 115, 24-35.
[17]. Yousefi, M., Kamkar-Rouhani, A., Carranza, E.J.M. (2014). Application of staged factor analysis and logistic function to create a fuzzy stream sediment geochemical evidence layer for mineral prospectivity mapping. Geochemistry: Exploration, Environment, Analysis. 14 (1): 45-58.
[18]. Sadeghi, B., Moarefvand, P., Afzal, P., Yasrebi, A.B., Saein, L.D. (2012). Application of fractal models to outline mineralized zones in the Zaghia iron ore deposit, Central Iran. Journal of Geochemical Exploration, 122, 9–19.
[19]. Sadeghi, B., Yilmaz, H., Pirajno, F. (2021). Weighting of BLEG data with drainage and catchment properties to enhance Au anomalies, Geochemistry. 81 (2): 125733.
[20]. Chen, G., Cheng, Q. (2018). Fractal-Based Wavelet Filter for Separating Geophysical or Geochemical Anomalies from Background. Mathematical Geosciences 50, 249-272.
[21]. Aliyari, F., Afzal, P., Lotfi, M., Shokri, S., Feizi, H. (2020). Delineation of geochemical haloes using the developed zonality index using multivariate and fractal analysis in the Cu-Mo porphyry deposits. Applied Geochemistry, 121, 104694.
[22]. Afzal, P., Yousefi, M., Mirzaei, M., Ghadiri-Sufi, E., Ghasemzadeh, S., Daneshvar Saein, L. (2019). Delineation of podiform-type chromite mineralization using Geochemical Mineralization Prospectivity Index (GMPI) and staged factor analysis in Balvard area (southern Iran). Journal of Mining and Environment 10: 705-715.
[23]. Kouhestani, H., Ghaderi, M., Afzal, P., Zaw, K. (2020). Classification of pyrite types using fractal and stepwise factor analyses in the Chah Zard gold-silver epithermal deposit, central Iran. Geochemistry: Exploration, Environment, Analysis 20, 496-508.
[24]. Torshizian, H., Afzal, P., Rahbar, K., Yasrebi, A.B., Wetherelt, A., Fyzollahhi, N. (2021). Application of modified wavelet and fractal modeling for detection of geochemical anomaly. Geochemistry, 125800.
[25]. Alavi, M. (1994). Tectonics of Zagros Orogenic belt of Iran, new data and interpretation. Tectonophysics 229, 211 –238.
[26]. Hashemi, M., Afzal, P., Rasa, I., Noghreian, M., Khosro Tehrani, Kh., Vosoughi Abedini, M. (2010). Geochemical anomaly separation by concentration-area fractal model in Bardaskan area, NE Iran. Journal of Mining and Metallurgy. 46 A (1): 1–10.
[27]. Hashemi, M., Afzal, P. (2013). Identification of geochemical anomalies by using of number-size (N-S) fractal model in Bardaskan area, NE Iran. Arabian Journal of Geosciences 6, 4785–4794.
[28]. Hamami Pour, B., Tajeddin, H.A., Barahmand, L. (2014). Geology and geochemistry of Sebandoon gold mine,north of Bardaskan: Example of epithermal gold mineralization in Ophiolitic host rocks. Conference: 18th Symposium of the Geological Society of Iran (In Persian with Enlish abstract).
[29]. Miri, H., Karimpour, M.H., Malekzadeh Shafaroudi, A. (2020). Geology, mineralization and geochemistry of Bijvard epithermal gold prospect area, Northern Bardaskan. Conference: 12th Symposium of the Geological Society of Iran (In Persian with Enlish abstract).
[30]. Abbasnia, H., Karimpour, M.H., Malekzadeh Shafaroudi, A. (2019). Damanghor intermediate sulfidation epithermal Au mineralization, Northern Bardaskan: geology, alteration, mineralization, and geochemistry. Iranian Journal of Crystallography and Mineralogy. 27(3): 621-634 (In Persian with Enlish abstract).
[31]. Zuo, R. (2011). Identifying geochemical anomalies associated with Cu and Pb–Zn skarn mineralization using principal component analysis and spectrum–area fractal modeling in the Gangdese Belt, Tibet (China). Journal of Geochemical Exploration, 111, 13-22.
[32]. Farahmandfar, Z., Jafari, M.R., Afzal, P., Ashja Ardalan, A. (2020). Description of gold and copper anomalies using fractal and stepwise factor analysis according to stream sediments in NW Iran. Geopersia. 10 (1): 135-148.
[33]. Muller J., Kylander, M., Martinez-Cortizas, A., Wüst, R.A.J., Weiss, D., Blake, K., Coles, B., Garcia-Sanchez, R. (2008). The use of principle component analyses in characterizing trace and major elemental distribution in a 55 kyr peat deposit in tropical Australia: implications to paleoclimate. Journal of Geochemistry Cosmochemistry Acta 72, 449-463.
[34]. Hajnajafi, Gh., Jafari Rad, A.R., Afzal, P., Sheikhzakariaei, S.J. (2021). Geological interpretation using multivariate K-means and robust factor analysis in Dezak area, SW Iran. Environmental Earth Sciences volume. 80 (1): 1-13.
[35]. Mandelbrot, B.B. (1983). The fractal geometry of nature. Freeman, San Fransisco.mineralized zones in the Zaghia iron ore deposit, Central Iran. Journal of Geochemical Exploration, 122: 9-19.