3D Zonation model of primary haloes and geochemical prospecting pattern of Aliabad Cu-Mo deposit, Yazd, Central Iran | ||
| روش های تحلیلی و عددی در مهندسی معدن | ||
| مقاله 1، دوره 11، شماره 29، اسفند 1400، صفحه 1-15 اصل مقاله (660.45 K) | ||
| نوع مقاله: مقاله پژوهشی | ||
| شناسه دیجیتال (DOI): 10.22034/anm.2022.1757 | ||
| نویسندگان | ||
| Mahdi Bemani؛ Seyyed Hossein Mojtahedzadeh* ؛ Abdolhamid Ansari | ||
| Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran | ||
| چکیده | ||
| Most hydrothermal ore deposits are controlled by geological structures. They are often a product of multistage hydrothermal activities, as a result, primary alteration haloes usually overlap in the vertical direction. By distinguishing the hydrothermal stages associated with ore-forming processes, one can determine the timings of hydrothermal activities and use the results as a method to identify blind mineralization. In order to explore probable blind mineralized zones of the Aliabad deposit, it is necessary to evaluate the element concentrations towards the depth or margins of the deposit. Modeling primary geochemical haloes could be useful in this stage. The Aliabad porphyry Cu-Mo deposit, located in the southern segment of Central Iran and adjacent to the northern border of the Urmia-Dokhtar volcanic belt and east of the Dehshir fault. Ore bodies at the Aliabad deposit are primarily controlled by structural features, which provide an opportunity to investigate the zonality in primary halos in this copper-molybdenum porphyry deposit. The primary geochemical characteristics of the mineral deposit were studied based on geochemical analysis of 1559 core samples from 24 drill holes. The formation of the primary geochemical haloes, which joins the ore body up to the surface, can be associated with hydrothermal fluid diffusion through fracture (fissures) zone developed in the rocks of the folding axis in the mining area. Along the vertical direction, the concentrations of Cu, Ag, and Fe shows an increasing trend from the surface to the ore body, at all boreholes; while the concentration of Pb, Mn, and Bi are decreased with depth at the same environment. A detailed zonality sequence of indicator elements is obtained using the variability index of these elements: Pb → (Bi, Mn, Mo) → Cr → Ni → (Sb, V, Zn) → (Ag, Co, Cu, Fe, S) → P. According to this zonality, indexes such as Vz4=Pb×Mn/Cu×Ag and Vz5=Pb×Mn/Cu×Ag×Co can be constructed and considered as a significant criterion for predicting the Cu potential at a particular depth. Studying the distribution of the zoning indexes at different levels revealed high values of proposed indexes in the northwest and south of the area. It can be concluded that copper mineralization will continue to deeper and unexplored parts of the deposit northwest of the study area. Consequently, it is suggested that further investigations concentrate on geophysical operations and it is highly recommended to drill additional boreholes at these areas. It is noteworthy that new drillings of the northwestern part must continue deeper than current boreholes (>150 m); because geochemical zonality indexes are extended to deeper parts. This extension is not observed for the southern part, so, additional drillings at the southern part can be shallower than 150 m. | ||
| کلیدواژهها | ||
| Aliabad porphyry Cu-Mo deposit؛ primary halos؛ Geochemical zonality؛ Zonality index؛ Block model | ||
| عنوان مقاله [English] | ||
| 3D Zonation model of primary haloes and geochemical prospecting pattern of Aliabad Cu-Mo deposit, Yazd, Central Iran | ||
| نویسندگان [English] | ||
| Mahdi Bemani؛ Seyyed Hossein Mojtahedzadeh؛ Abdolhamid Ansari | ||
| Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran | ||
| چکیده [English] | ||
| Most hydrothermal ore deposits are controlled by geological structures. They are often a product of multistage hydrothermal activities, as a result, primary alteration haloes usually overlap in the vertical direction. By distinguishing the hydrothermal stages associated with ore-forming processes, one can determine the timings of hydrothermal activities and use the results as a method to identify blind mineralization. In order to explore probable blind mineralized zones of the Aliabad deposit, it is necessary to evaluate the element concentrations towards the depth or margins of the deposit. Modeling primary geochemical haloes could be useful in this stage. The Aliabad porphyry Cu-Mo deposit, located in the southern segment of Central Iran and adjacent to the northern border of the Urmia-Dokhtar volcanic belt and east of the Dehshir fault. Ore bodies at the Aliabad deposit are primarily controlled by structural features, which provide an opportunity to investigate the zonality in primary halos in this copper-molybdenum porphyry deposit. The primary geochemical characteristics of the mineral deposit were studied based on geochemical analysis of 1559 core samples from 24 drill holes. The formation of the primary geochemical haloes, which joins the ore body up to the surface, can be associated with hydrothermal fluid diffusion through fracture (fissures) zone developed in the rocks of the folding axis in the mining area. Along the vertical direction, the concentrations of Cu, Ag, and Fe shows an increasing trend from the surface to the ore body, at all boreholes; while the concentration of Pb, Mn, and Bi are decreased with depth at the same environment. A detailed zonality sequence of indicator elements is obtained using the variability index of these elements: Pb → (Bi, Mn, Mo) → Cr → Ni → (Sb, V, Zn) → (Ag, Co, Cu, Fe, S) → P. According to this zonality, indexes such as Vz4=Pb×Mn/Cu×Ag and Vz5=Pb×Mn/Cu×Ag×Co can be constructed and considered as a significant criterion for predicting the Cu potential at a particular depth. Studying the distribution of the zoning indexes at different levels revealed high values of proposed indexes in the northwest and south of the area. It can be concluded that copper mineralization will continue to deeper and unexplored parts of the deposit northwest of the study area. Consequently, it is suggested that further investigations concentrate on geophysical operations and it is highly recommended to drill additional boreholes at these areas. It is noteworthy that new drillings of the northwestern part must continue deeper than current boreholes (>150 m); because geochemical zonality indexes are extended to deeper parts. This extension is not observed for the southern part, so, additional drillings at the southern part can be shallower than 150 m. | ||
| کلیدواژهها [English] | ||
| Aliabad porphyry Cu-Mo deposit, primary halos, Geochemical zonality, Zonality index, Block model | ||
| مراجع | ||
|
[1] Safronov, N. I. (1936) Dispersion haloes of ore deposits and their use in exploration. Probl. Sov. Geol. 4, 41–53. [2] Li, Y., Zhang, D., Dai, L., Wan, G. and Hou, B. (2016) Characteristics of structurally superimposed geochemical haloes at the polymetallic Xiasai silver-lead-zinc ore deposit in Sichuan Province, SW China. J. Geochemical Explor., Elsevier B.V. 169, 100–122. [3] Carranza, E. J. M. (2012) Primary geochemical characteristics of mineral deposits: implications for exploration. Ore Geol. Rev., Elsevier 45, 1–4. [4] Goldberg, I. S., Abramson, G. Y. and Los, V. L. (2003) Depletion and enrichment of primary haloes: their importance in the genesis of and exploration for mineral deposits. Geochemistry Explor. Environ. Anal., Geological Society of London 3, 281–293. [5] Govett, G. J. S. 1983, Rock geochemistry in mineral exploration: Handbook of exploration geochemistry, v. 3, Amsterdam, Elsevier. [6] Bierlein, F. P., Fuller, T., Stüwe, K., Arne, D. C. and Keays, R. R. (1998) Wallrock alteration associated with turbidite-hosted gold deposits. Examples from the Palaeozoic Lachlan Fold Belt in central Victoria, Australia. Ore Geol. Rev., Elsevier 13, 345–380. [7] Hannington, M. D., Santaguida, F., Kjarsgaard, I. M. and Cathles, L. M. (2003) Regional-scale hydrothermal alteration in the Central Blake River Group, western Abitibi subprovince, Canada: implications for VMS prospectivity. Miner. Depos., Springer 38, 393–422. [8] Beus, A. A. and Grigorian, S. V. (1977) Geochemical exploration methods for mineral deposits, Applied Publishing Ltd., Wilmette, IL. [9] Xie, X. and Shao, Y. (1965) The method of work and interpretation of geochemical rock survey. Geophys. Geochem. Explor. Res. Bull. 5, 2–7. [10] Chongmin, L. and Waisheng, X. (1995) Primary geochemical anomalies in the Caijiaying Pb-Zn-Ag deposits, Hebei, China. J. Geochemical Explor. 55, 25–32. [11] Liu, C., Hu, S., Ma, S. and Tang, L. (2014) Primary geochemical patterns of Donggua Mountain laminar skarn copper deposit in Anhui, China. J. Geochemical Explor., Elsevier B.V. 139, 152–159. [12] Harris, J. R., Wilkinson, L. and Grunsky, E. C. (2000) Effective use and interpretation of lithogeochemical data in regional mineral exploration programs: application of Geographic Information Systems (GIS) technology. Ore Geol. Rev., Elsevier 16, 107–143. [13] Ziaii, M., Carranza, E. J. M. and Ziaei, M. (2011) Application of geochemical zonality coefficients in mineral prospectivity mapping. Comput. Geosci., Elsevier 37, 1935–1945. [14] Berberian, M. and King, G. C. P. (1981) Towards a paleogeography and tectonic evolution of Iran. Can. J. Earth Sci., NRC Research Press 18, 210–265. [15] Amooyi Ardakani, A. (1998) Investigation of Petrology of Khezr Abad Intrusive Mass, Shahid Beheshti University. [16] Padir Consulting Engineers. (2001) Geological Surveys of Ali Abade Yazd. [17] John, D. A., Ayuso, R. A., Barton, M. D., Bodnar, R. J., Dilles, J. H., Gray, F., Graybeal, F. T., Mars, J. C., McPhee, D. K., Seal, R. R., et al. (2010) Porphyry Copper Deposit Model Scientific Investigations Report 2010 – 5070 – B. USGS Sci. Investig. Rep. 2010-5070-B 169. [18] Lowell, J. D. and Guilbert, J. M. (1970) Lateral and vertical alteration-mineralization zoning in porphyry ore deposits. Econ. Geol., Society of Economic Geologists 65, 373–408. [19] Bemani, M., Mojtahedzade, S. H. and Ansari, A. (2020) Geology, petrology, alteration and mineralization of Aliabad-Damak copper ore deposit. Iran. J. Crystallogr. Mineral. under revi. [20] Samiee, S., Karimpoor, M. H., Ghaderi, M. and Heydarian Shahri, M. R. (2013) Geology, alteration, mineralization and geochemistry of Khunik area, south of Birjand. Iran. J. Crystallogr. Mineral. 21, 487–498. [21] Miri Beydokhti, R., Karimpour, M. H. and Mazaheri, S. A. (2014) Studies of remote sensing, geology, alteration, mineralization and geochemistry of Balazard copper-gold prospecting area, west of Nehbandan. Iran. J. Crystallogr. Mineral. 22, 459–470. [22] Azadi, M., Mirmohammadi, M. and Hezarkhani, A. (2014) Petrology and fluid inclusion studies in Kahang porphyry copper deposit. Iran. J. Crystallogr. Mineral. 22, 155–172. [23] Kaviani, A., Hatzfeld, D., Paul, A., Tatar, M. and Priestley, K. (2009) Shear-wave splitting, lithospheric anisotropy, and mantle deformation beneath the Arabia-Eurasia collision zone in Iran. Earth Planet. Sci. Lett. 286, 371–378. [24] Molayemat, H., Torab, F. M., Pawlowsky-Glahn, V., Hossein Morshedy, A. and Egozcue, J. J. (2018) The impact of the compositional nature of data on coal reserve evaluation, a case study in Parvadeh IV coal deposit, Central Iran. Int. J. Coal Geol., Elsevier 188, 94–111. [25] Afzal, P., Alghalandis, Y. F., Khakzad, A., Moarefvand, P. and Omran, N. R. (2011) Delineation of mineralization zones in porphyry Cu deposits by fractal concentration--volume modeling. J. Geochemical Explor., Elsevier 108, 220–232. [26] Afzal, P., Dadashzadeh, H., Rashidnejad, N. and Aliyari, F. (2013) Delineation of gold mineralized zones using concentration – volume fractal model in Qolqoleh gold deposit , NW Iran. Ore Geol. Rev., Elsevier B.V. 55, 125–133. [27] Afzal, P., Hosein, S., Tokhmechi, B. and Kaveh, D. (2014) International Journal of Coal Geology Outlining of high quality coking coal by concentration – volume fractal model and turning bands simulation in East-Parvadeh coal deposit , Central Iran. Int. J. Coal Geol., Elsevier B.V. 127, 88–99. [28] Hassani Pak, A. A. (2010) Principles of geochemical exploration, University of Tehran Press. Tehran. [29] Kitaev, N. A. (1991) Multidimensional analysis of geochemical fields. Math. Geol., Springer 23, 15–32. [30] Grigorian, S. V. (1992) Mining geochemistry. Nedra, Moscow. [31] Ziaii, M., Pouyan, A. A. and Ziaei, M. (2009) Neuro-fuzzy modelling in mining geochemistry: identification of geochemical anomalies. J. Geochemical Explor., Elsevier 100, 25–36. [32] Ziaii, M., Abedi, A. and Ziaei, M. (2009) Geochemical and mineralogical pattern recognition and modeling with a Bayesian approach to hydrothermal gold deposits. Appl. Geochemistry, Elsevier 24, 1142–1146. [33] Solovov, A. P. and Kuznetov, V. V. (1987) Geochemical prospecting for mineral deposits, Mir Publ. [34] Solovov, A. P. (1990) Handbook on geochemical prospecting for useful minerals, Nedra Publishing House, Moscow [in Russian]. [35] Ziaii, M. (1996) Lithogeochemical exploration methods for cupper-porphyry deposit in Sungun, NW Iran. Unpubl. M. Sc. thesis. Geochemistry Fac. MSU, Moscow.
| ||
|
آمار تعداد مشاهده مقاله: 813 تعداد دریافت فایل اصل مقاله: 769 |
||