Enhancing core recovery and RQD analysis in porphyry Cu deposits through fractal modeling, case study: Sungun mine (NW Iran)

Document Type : Research Paper

Authors

1 Pouya Mes Iranian Company, Tehran, Iran.

2 Department of Petroleum and Mining Engineering, Islamic Azad University, Tehran, Iran.

3 Earth and Sustainability Science Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Australia.

4 CSIRO Mineral Resources, Australian Resources Research Centre, Kensington, Australia.

5 Department of Geology, Payame Noor University, Tehran, Iran.

10.22059/ijmge.2025.383290.595200

Abstract

Interpreting core samples is a critical task in mineral exploration, essential for mine planning and design. Core Recovery (CR) and Rock Quality Designation (RQD) are key factors in assessing the geomechanical properties of a deposit during coring operations. This is particularly important in porphyry deposits, which are notable for hosting significant, deep copper mines. The accurate determination and interpretation of core recovery and RQD are crucial for these porphyry deposits. This study applied number-size (N-S) fractal modelling to enhance the interpretation of core recovery and RQD in ongoing exploratory drilling at the Sungun porphyry deposit, a prominent copper mine in Iran. Our findings revealed that core recovery and RQD exhibited a multifractal nature. Key zones for core recovery and RQD began at thresholds of 75% and 63%, respectively, with high-intensity zones for both parameters started at 89%. Additionally, the study explored correlations between these zones and other drilling parameters, such as mud flush return, drilling time, and core length, using an overall accuracy (OA) matrix. These parameters were analyzed using the N-S fractal model, indicated a strong relationship between core recovery, core length, flush returns, and drilling time. This integrative approach enhances our understanding of the deposit's geomechanical properties and guides more effective exploration strategies.

Keywords

Main Subjects

References

[1] Zhang, L., 2016. Determination and applications of rock quality designation (RQD). Journal of Rock Mechanics and Geotechnical Engineering 8(3), 389-397.
[2] Hustrolid W., Kuchta M., 2006. Open Pit Mine Planning and Design (2th Edition). 972 p.
[3] Aalizad, S.A., Rashidinejad, F., 2012. Predication of Peneteration Rate of Rotary-Percussive Drilling Using Artificaial Neural Networks – A Case Study. Arch. Min. Sci. 57 (3), 715–728.
[4] Yasrebi, A.B., Wetherelt, A., Foster, P.J., Afzal, P., Coggan, J., Ahangaran, D.K., 2013. Application of RQD-Number and RQD-Volume multifractal modelling to delineate rock mass characterisation in Kahang Cu-Mo porphyry deposit, central Iran. Archives of Mining Sciences 58 (4), 1023-1035.
[5] Chen, Q., Yin, T., Niu, W. 2018. Replacing RQD and Discontinuity Spacing with the Modified Blockiness Index In the Rock Mass Rating System. Arch. Min. Sci. 63 (2), 353-382.
[6] Hasan, M., Shang, Y., Yi, X., Shao, P., He, M., 2023. Determination of rock mass integrity coefficient using a non-invasive geophysical approach. Journal of Rock Mechanics and Geotechnical Engineering 15(6), 1426-1440.
[7] Hasan, M., Shang, Y., Meng, Q., 2023. Evaluation of rock mass units using a non-invasive geophysical approach. Scientific Reports  13, 14493.
[8] Pirajno, F., 2009. Hydrothermal Processes and Mineral Systems. Springer, 1250 p.
[9] 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. Iranian Journal of Earth Sciences 2, 64-72.
[10] Aghazadeh, M., Hou, Z., Badrzadeh, Z., & Zhou, L., 2015. Temporal spatial distribution and tectonic setting of porphyry copper deposits in Iran: Constraints from zircon U-Pb and molybdenite Re–Os geochronology. Ore Geology Reviews 70, 385–406.
[11] Yasrebi, A.B., Wetherelt, A., Foster, P., Coggan, J., Afzal, P., Agterberg, F., Kaveh Ahangaran, D., 2014. Application of a density–volume fractal model for rock characterisation of the Kahang porphyry deposit. International Journal of Rock Mechanics and Mining Sciences 66, 188-193.
[12] Mahdizadeh, M., Afzal, P., Eftekhari, M., Ahangari, K., 2022. Geomechanical zonation using multivariate fractal modeling in Chadormalu iron mine, Central Iran. Bulletin of Engineering Geology and the Environment 81 (1), 59
[13] Malaekeh, A., Ghassemi, 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 81 (4), 125803.
[14] -   Monjezi, M., Baghestani, M., Afzal, P., Yarahmadi Bafghi, A.R., Hashemi, S.A., 2024. Investigation on Relationship between Rock Characteristics and Blasting Fragmentation using Fractal Analysis. Journal of Mining and Environment 10.22044/jme.2024.15240.2917
[15] Agterberg F.P., 1995. Multifractal modeling of the sizes and grades of giant and supergiant deposits. International Geology Review 37, 1–8.
[16] Cheng, Q., 1999. Multifractality and spatial statistics. Comput. Geosci. 25, 949-961.
[17] Cheng, Q., Agterberg, F.P., Ballantyne S.B., 1994. The separation of geochemical anomalies from background by fractal methods. Journal of Geochemical Exploration 51, 109-130.
[18] Li, C., Ma, T., Shi, J., 2003. Application of a fractal method relating concentrations and distances for separation of geochemical anomalies from background. Journal of Geochemical Exploration 77, 167-175.
[19] Afzal, P., Alghalandis, Y.F., Khakzad, A., Moarefvand, P., Rashidnejad Omran, N., 2011. Delineation of mineralization zones in porphyry Cu deposits by fractal concentration–volume modeling. Journal of Geochemical exploration 108 (3), 220-232
[20] Afzal, P., Alghalandis, Y.F., Moarefvand, P., Rashidnejad Omran, N., Asadi Haroni, H., 2012. Application of power-spectrum–volume fractal method for detecting hypogene, supergene enrichment, leached and barren zones in Kahang Cu porphyry deposit, Central Iran. Journal of Geochemical Exploration 112, 131-138.
[21] Ghosh, A., Daemen J.J., Van Zyl D., 1990. Fractal-based approach to determine the effect of discontinuities on blast fragmentation. In: The 31th US Symposium on Rock Mechanics (USRMS), American Rock Mechanics Association.
[22] Pourgholam, M.M., Afzal, P., Adib, A., Rahbar, K., Gholinejad M., 2024. Recognition of REEs anomalies using an image Fusion fractal-wavelet model in Tarom metallogenic zone, NW Iran. Geochemistry, 126093.
[23] Afzal, P., Abdideh, M., Daneshvar Saein, L., 2023. Separation of productivity index zones using fractal models to identify promising areas of fractured reservoir rocks. Journal of Petroleum Exploration and Production Technology 13 (9), 1901-1910.
[24] Crum, S.V., 1990. Fractal concepts applied to bench-blast fragmentation. In: Proc. 3rd US Rock Mech. Symp. Balkema, Rotterdam 913–919..
[25] Daneshvar Saein, L., Afzal, P., 2017. Correlation between Mo mineralization and faults using geostatistical and fractal modeling in porphyry deposits of Kerman Magmatic Belt, SE Iran. Journal of Geochemical Exploration 181, 333-343.
[26] Koohzadi, F., Afzal, P., Jahani, D., Pourkermani, M., 2021. Geochemical exploration for Li in regional scale utilizing Staged Factor Analysis (SFA) and Spectrum-Area (SA) fractal model in north central Iran. Iranian Journal of Earth Sciences 13 (4), 299-307.
[27] Sadeghi, B., 2024. Fractals and Multifractals in the Geosciences. Elsevier, Amsterdam (https://doi.org/10.1016/B978-0-323-90897-9.00010-9).
[28] Aghazadeh, M.; Hou, Z.; Badrzadeh, Z.; Zhou, L. Temporal–spatial distribution and tectonic setting of porphyry copper deposits in Iran: Constraints from zircon U–Pb and molybdenite Re–Os geochronology. Ore Geol. Rev. 2015, 70, 385–406.
[29] Zürcher, L.; Bookstrom, A.A.; Hammarstrom, J.M.; Mars, J.C.; Ludington, S.; Zientek, M.L.; Dunlap, P.; Wallis, J.C.; Drew, L.J.; Sutphin, D.M.; et al. Porphyry Copper Assessment of the Tethys Region of Western and Southern Asia: Chapter V in Global Mineral Resource Assessment; US Geological Survey: Reston, VA, USA, 2015.
[30] Richards, J.P.; Sholeh, A. 2016. The Tethyan tectonic history and Cu-Au metallogeny of Iran. Econ. Geol. Spec. Publ. 19, 193–212.
[31] Ehlen, J., 2000. Fractal analysis of joint patterns in grantie. Int J Rock Mech Min Sci 37(6), 909–922.
[32] Kamali, A.A., Moayyed, M., Amel, N., Hosseinzadeh, M.R., Mohammadiha, K., Santos, J.F., Brenna, M. 2018. Post-Mineralization, Cogenetic Magmatism at the Sungun Cu-Mo Porphyry Deposit (Northwest Iran): Protracted Melting and Extraction in an Arc System. Minerals, 8(12), 588.
[33] Kou, G.Y., Xu, B., Zhou, Y., Zheng, Y.C., Hou, Z.Q., Zhou, L.M., Zhang, Y.F., Yu, J.X. 2021. Geology and petrogenesis of the Sungun deposits: Implications for the genesis of porphyry-type mineralisation in the NW Urumieh–Dokhtar magmatic Arc, Iran. Ore Geology Reviews 131, 104013.
[34] Talesh Hosseini, S., O. Asghari, Torabi, S.A., Abedi, M. 2020. An Optimum Selection of Simulated Geological Models by Multi-Point Geostatistics and Multi-Criteria Decision-Making Approaches; a Case Study in Sungun Porphyry-Cu deposit, Iran. Journal of Mining and Environment 11(2), 481-503.
[35] Mandelbrot B.B., 1983. The Fractal Geometry of Nature. W.H. Freeman, San Francisco, CA. Updated and Augmented Edition.
[36] Ahmadi, N.R., Afzal, P., Yasrebi, A.B., 2021. Delineation of gas content zones using NS fractal model in coking coal deposits. Journal of Mining and Environment 12 (1), 181-189
[37] Ficker, T., 2017. Fractal properties of joint roughness coefficients. Int J Rock Mech Min Sci 94, 27–31.
[38] Sadeghi, B., 2021. Simulated-multifractal models: a futuristic review of multifractal modeling in geochemical anomaly classification. Ore Geology Reviews, 139 (Part B) (https://doi.org/10.1016/j.oregeorev.2021.104511).
[39] Hassanpour, S., Afzal, P., 2013. Application of concentration–number (C–N) multifractal modeling for geochemical anomaly separation in Haftcheshmeh porphyry system, NW Iran. Arabian Journal of Geosciences 6, 957-970
[40] Carranza, E.J.M., 2011. Analysis and mapping of geochemical anomalies using logratio-transformed stream sediment data with censored values. Journal of Geochemical Exploration 110: 167-185.
[41] Nikzad, M.R., Asadi, A., Kaveh Ahangaran, D., Yasrebi, A.B. Wetherelt, A., Afzal, P., 2018. Application of fractal modelling to classify blast fragmentation and size distributions. Archives Mining of Sciences 63(3), 783-796.
International Journal of Mining and Geo-Engineering
Volume 59, Issue 1
March 2025
Pages 69-74

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