نوع مقاله : مقاله پژوهشی

نویسندگان

پژوهشکده چرخه سوخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران، صندوق پستی: 8486-11365، تهران- ایران

چکیده

کانسار فسفات دلیر در 57 کلیومتری جنوب غربی شهر چالوس در استان مازندران و زون البرز مرکزی دارد. میزبان این ذخیره سازند سلطانیه است که یکی از مهم‌ترین سازندهای میزبان فسفات رسوبی در ایران است. نتایج آنالیز پراش اشعه ایکس (XRD) و مطالعات میکروسکوپ نوری و الکترونی بر روی نمونه‌های فسفات کانسار دلیر نشان داد که آپاتیت، کلسیت، کوارتز و دولومیت کانی‌های اصلی و کانی‌های فرعی شامل مونتموریلونیت، پیریت و باریت در مقادیر فرعی به همراه مقادیر جزیی سیدریت، روتیل، ایلیت و گوتیت هستند. میزان 5O2P، U و REE در نمونه‌های موردمطالعه به ترتیب در محدوده 5 تا 1/16 درصد، 9/1 تا 5/5 و 9/45 تا 9/136 پی پی ام متغیر است. نمونه‌های موردمطالعه دارای بی­هنجاری منفی Ce است که نشان‌­دهنده وجود یک محیط فاقد اکسیژن در زمان نهشت فسفات دلیر می‌باشد. براساس فاکتورهای کنترل‌­کننده تمرکز اورانیم در فسفریت‌ها، افق فسفاته سازند سلطانیه به دلیل شرایط آب و هوای گرم تا نیمه‌گرم مرطوب و pH خنثی تا اسیدی آب دریا در زمان تشکیل فسفات، پتانسیل غنی‌شدگی‌ اورانیم را ندارد. در نهایت، با توجه به این­‌که نتایج آنالیز شیمیایی نمونه‌های فسفات کانسار دلیر غنی‌شدگی‌ اورانیم نشان نمی‌دهد و هم‌­چنین با در نظر گرفتن فاکتورهای کنترل­‌کننده تمرکز اورانیم در فسفریت‌ها می‌توان پیش­‌بینی کرد احتمالاً سایر ذخایر فسفات سازند سلطانیه فاقد غنی‌شدگی‌ اورانیم هستند.

کلیدواژه‌ها

عنوان مقاله [English]

Geochemistry of uranium and REEs in Dalir phosphate deposit, Central Alborz zone

نویسندگان [English]

  • K. Khoshnoodi
  • S. Ziapour

Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box:11365-8486, Tehran-Iran

چکیده [English]

The Dalir phosphate deposit is located 57 km southwest of Chalus city in Mazandaran province, the Central Alborz zone. This deposit is hosted by Soltanieh Formation, one of Iran's important hosts of sedimentary phosphates. The results of X-ray diffraction (XRD) analysis and optical and electron microscopy studies on the phosphate samples indicate that the main minerals include apatite, calcite, quartz, and dolomite accompanied by montmorillonite, pyrite, and barite in minor amounts; siderite, rutile, illite, and goethite in trace amounts. The concentration of P2O5, U, and REEs in the studied samples ranged from 5 to 16.1%, 1.9 to 5.5, and 45.9 to 136.9 ppm, respectively. The studied samples have negative Ce anomaly, indicating an anoxic environment during the Dalir phosphate deposition. Based on the factors controlling uranium concentration in phosphorites, the phosphate horizon of Soltanieh Formation does not have uranium enrichment potential due to warm to semi-warm humid paleoclimate with neutral to acidic pH of the seawater during the Dalir phosphate deposition in lower Cambrian. Finally, considering the results of the chemical analysis of phosphate samples of the Dalir deposit (lack of uranium enrichment) and also the factors controlling uranium concentration in phosphorites, it can be predicted that the other phosphate deposits of Soltanieh Formation probably not be uranium enriched.

کلیدواژه‌ها [English]

  • Dalir deposit
  • Soltanieh formation
  • Uranium
  • Ce anomaly
  1. A. Aksoy, et al., Gamma-ray spectroscopic and PIXE analysis of selected samples from the phosphorite deposits of northwestern Saudi Arabia, J. Radioanal Nucl. Chem., 253(3), 517 (2002).

 

  1. G.H. McClellan, J.R. Lehr, Crystal chemical investigation of natural apatites, Am. Miner., 54, 1374 (1969).

 

  1. P.J. Cook, M.W. Mc Elhinny, A reevaluation of the spatial and temporal distribution of sedimentary phosphate deposits in the light of plate tectonics, Econ. Geol., 74, 315 (1979).

 

  1. J.M. Guilbert, C.F Park, The geology of ore deposits, 1st ed. (Waveland Press, Inc, New York, 1986).

 

  1. G.N. Baturin, A.V. Kochenov, Uranium in phosphorites, Lithol. Miner. Resour., 36(4), 303 (2001).

 

  1. A.V. Kochenov, G.N. Baturin, The paragenesis of organic matter, phosphorus, and uranium in marine sediments, Lithol. Miner. Resour., 37(2), 107 (2002).

 

  1. Z.S. Altschuler, The geochemistry of trace elements in marine phosphorites: Part 1, characteristic abundances and enrichment, Spec. Publ. SEPM., 29, 19 (1980).

 

  1. J.B. Cathcart, Uranium in phosphate rock, 1st ed. (Geological Survey Professional Paper 988-A, U.S. Geological Survey, Washington, 1978).

 

  1. A.M. Abed, R.M. Sadaqah, Enrichment of uranium in the uppermost Al-Hisa Phosphorite Formation, Eshidiyya Basin, Southern Jordan, J. Afr. Earth. Sci., 77, 31 (2013).

 

  1. E. Schnug, N. Haneklaus, Uranium, the hidden treasure in phosphates, Procedia Eng., 83, 265 (2014).

 

  1. H. Halalat, M.H. Bolourchi, Geology of Iran: Phosphate, 1st ed. (Geological Survey and Mineral Exploration of Iran, Tehran, 1994) (in Persian).

 

  1. A. Namadmalian, L. Malekzadeh, Exploration of phosphate in Dalir deposit (Report of Geological Survey and Mineral Exploration of Iran, Tehran, 1984) (In Persian).

 

  1. M. Cheshmehsari, M.S. Thesis, University of Urmia, (2012) (In Persian).

 

  1. M. Cheshmehsari, et al., Mineralogy and geochemistry of rare earth elements at the Dalir phosphatic horizon (SW of Chalous, Mazandaran province), J. Econ. Geol., 4, 319 (2013) (In Persian).

 

  1. A. Namadmalian, L. Malekzadeh, K. Sadeghi, K., Exploration Programme of Phosphate: Detailed studies of Dalir and 1:2000 map (Report of Geological Survey and Mineral Exploration of Iran, Tehran, 1362) (In Persian).

 

  1. M. Cheshmehsari, A. Abedini, A. Alizadeh, In: 31th Conference of Geoscience, Factors controlling U distribution in Dalir phosphates, southwest Chalus, Mazandaran (Geological Survey and Mineral Exploration of Iran, Tehran), 1-7 (2012) (In Persian).

 

  1. K. Khoshnoodi, S. Ziapour, In: Geochemical and Mineralogical Characterization of Uranium and Thorium Deposits, Edited by IAEA (IAEA, Vienna), 93-124 (2020).

 

  1. F.J. Dahlkamp, Uranium ore deposits, 1st ed. (Springer- Verlag, Berlin, 1993).

 

  1. J. Lucas, M. Abbas, Uranium in natural phosphorites: Syrian example, Bull. Sci. Geol. Strasbourg, 42, 223 (1989).

 

  1. J.M. Bremner, Brief Description of a West-Coast Phosphorite Deposit (Report of Geological Survey of South Africa, 0100, South Africa, 1992).

 

  1. N.A. Titayeva, Nuclear geochemistry, 1st ed. (CRC Press, Florida, 1994).

 

  1. A.V. Kochenov, V.T. Dubinchuk, E.V. Germogenova, The form of uranium occurrence in phosphate remains of fossil fishes, Sov. Geol., 3, 60 (1973).

 

  1. G.Y. Ostrovskaya, Uranium in rocks of phosphorite-bearing formations, Sov. At. Energy, 36, 189 (1974).

 

  1. H. Kimura, et al., The Vendian-Cambrian δ13C record, north Iran: Evidence for overturning of the ocean before the Cambrian explosion, Earth and Planet. Sci. Lett., 147, 1 (1997).

 

  1. J. Sharifi, Ph.D Thesis, Ankara University, (2002).

 

  1. N. Abedian, Phosphate Prospecting in Gilan Province (Report of Geological Survey and Mineral Exploration of Iran, Tehran, 2008) (In Persian).

 

  1. M. Kazemi, et al., In: 31th Conference of Geoscience, Explaining Mineralization related to Genesis and Evolution of Proto- and Paleo- Tethys in Alborz Zone (Geological Survey and Mineral Exploration of Iran, Tehran), 1-8 (2012) (In Persian).

 

  1. M. Cheshmehsari, et al., In: 4th Conference of Economic Geology of Iran, Trace Element Geochemistry of the Dalir Phosphate Deposit, Southwest of Chalous, Mazandaran (Islamic Azad University of Isfahan, Isfahan), 255-260 (2012) (In Persian).

 

  1. H. Mousavi, et al., In: 33th National Geosiences Symposium, Geochemical Investigation of Rare Earth Elements (REE) in Soltanieh Formation Phosphatic Horizon, Seyed Kandi Section, Southwest Zanjan. Iran, (Geological Survey and Mineral Exploration of Iran, Tehran), 1-19 (2015) (In Persian).

 

  1. M. Slansky, Geology of sedimentary phosphates, 1st ed. (North Oxford Academic, London, 1986).

 

  1. G.S. Awadalla, Geochemistry and microprobe investigations of Abu Tartur REE-bearing phosphorite, Western Desert, Egypt, Afr. Earth Sci., 57, 431 (2010).

 

  1. G.J. Simandl, S. Paradis, R. Fajber, Sedimentary Phosphate Deposits, 1st ed. (British Columbia Ministry of Energy, Mines and Petroleum Resources, 2012).

 

  1. J.O. Nriagu, P.B. Moore, Phosphate minerals, 1st ed. (Springer, Berlin, 1984).

 

  1. S.R. Taylor, S.M. McLennan, The continental crust: Its composition and evolution, 1st ed. (Blackwell, Oxford, 1985).

 

  1. G. Shields, P. Stille, Diagenetic constraints on the use of cerium anomalies as palaeoseawater redox proxies: an isotopic and REE study of Cambrian phosphorites, Chem. Geol., 175, 29 (2001).

 

  1. M. Bau, P. Dulski, Distribution of yttrium and rare earth elements in the Penge and Kuruman iron-formations, Transvaal Supergroup, South Africa, Precambrian Res., 79, 37 (1996).

 

  1. H. Elderfield, M.J. Greaves, The rare earth elements in seawater, Nature, 296, 214 (1982).

 

  1. K.F. Khan, S.A. Dar, S.A. Khan, Rare earth element (REE) geochemistry of phosphorites of the sonrai area of Paleoproterozoic Bijawar Basin, Uttar Pradesh, India, J. Rare Earths, 30(5), 507 (2012).

 

  1. H. Rollinson, Using geochemical data: evaluation, presentation, interpretation, 2nd ed. (Cambridge University Press, London, 2021).

 

  1. C.R. German, H. Elderfield, Application of the Ce anomaly as a paleoredox indicator: the ground rule, Paleoceanography., 5, 823 (1990).

 

  1. B. Reynard, C. Lecuyer, P. Grandjean, Crystal-chemical controls on rare earth element concentrations in fossil biogenic apatites and implications for paleoenvironmental reconstructions, Chem. Geol., 155, 233 (1999).

 

  1. S.J. Moghaddasi, Mineralogy and rare earth elements geochemistry of Jeirud phosphate deposit in Shemshak valley, North Tehran, Geosciences, 26, 313-324 (2017) (In Persian).