GM  Vol.3 No.3 , July 2013
Preliminary Study on HFSE Mineralization in the Peralkaline Granites of Nusab El Balgum Area, South Western Desert, Egypt
Abstract: Nusab El Balgum mass complex represents one of peralkaline volcanic activity phenomena in the south Western Desert of Egypt, which is typical for within-plate event, which formed in Mesozoic period. It consists of acidic volcanic (rhyolite and their pyroclastics) and sub-volcanic granitic rocks (incomplete ring, small stock and dyke of a peralkaline aphanites) as well as dykes (trachyte, bostonite, rhyodacite, rhyolite and porphyritic rhyolite) variable in thickness and the most of run in NNE-SSW trend. The peralkaline granitic rocks, especially those located at the southwestern part of this mass are characterized by extreme enrichments in HFSE (rare metals such as Zr, Nb, U and Th and REEs) which are the highest concentrations (e.g., >1% Zr, 0.5% Nb and 2.6% total REEs, Y up to 1%, eU up to 300 ppm and eTh up to 1100 ppm). The rare metal bearing minerals are thorite, uranothorite, autunite, amorphous secondary uranium, zircon and ferrocolumbite, while the REEs bearing minerals are bastnaesite, monazite and xenotime. The positive relations in all of the binary diagrams of Zr versus Nb, Y, eU and eTh, Nb versus Y, eU and eTh, Y versus eU and eTh in post magmatic intensely hematised peralkaline granites indicated that, this process is responsible for the enrichment in these HFSE. The chondrite-normalized pattern of high-altered peralkaline granites indicates: 1) higher LREEs enriched pattern (La/Gd = 11.34 and 12.25) means the alteration processes taking place under open system and these rocks evolved from magma of lithospheric rifting, 2) ΔCe < 1 anomaly, means that the alteration fluids were slightly oxic and 3) strong negative—ΔEu < 1. This indicates the nature of residual peralkaline melt: a) it was extremely rich in fluorine, H2O, and thus very low viscosity, despite its low temperature (<650°C); b) it was strong depleted in feldspar-compatible elements, as indicated by strong negative Eu anomalies; and c) it had abundances of HFSE cations. Redistribution of elements took place by post magmatic hydrothermal solutions.
Cite this paper: S. Elatta, H. Assran and A. Ahmed, "Preliminary Study on HFSE Mineralization in the Peralkaline Granites of Nusab El Balgum Area, South Western Desert, Egypt," Geomaterials, Vol. 3 No. 3, 2013, pp. 90-101. doi: 10.4236/gm.2013.33012.

[1]   V. I. Kovalenko, G. M. Tsaryeva, A. V. Goreglyad, V. V. Yarmoluk and V. A. Troitsky, “The Peralkaline-Granite Related Khaldzan-Buregtey Rare Metal (Zr, Nb, REE) Deposit, Western Mongolia,” Economic Geology, Vol. 90, No. 3, 1955, pp. 530-547. doi:10.2113/gsecongeo.90.3.530

[2]   Z. Hadj-Kaddor, J. P. Liegeois, D. Demaifffe and R. Caby, “The Alkaline—Peralkaline Granitic Post—Collisional Tin Zebane Dyke Swarm (Pan-African Shield Algeria): Pre Valent Mantle Signature and Late Agpaitic Differentiation,” Lithos, Vol. 45, No. 1-4, 1998, pp. 223-243. doi:10.1016/S0024-4937(98)00033-4

[3]   S. Salvi and A. E. Williams-Jones, “Alteration HFSE Mineralization and Hydrocarbon Formation in Peralkaline Igneous System Insight from the Lake Strange Pluton, Canada,” Lithos, Vol. 91, No. 1-4, 2006, pp. 19-34. doi:10.1016/j.lithos.2006.03.040

[4]   C. Peiffert, C. Nguyen-Trung and M. Cuney, “Uranium in Granitic Magmas: Part 2 Experimental Determination of Uranium Solubility and Fluid-Milt Partition Coefficient in the Uranium Oxides-Haplogranite-H2O-NaX (X=Cl, F) system at 770°C, 2 Kbar,” Geochimica et Comsmochimica Acta, Vol. 60, 1966, pp. 659-662.

[5]   R. I. Linen and H. Keppler, “Columbite Solubility in Granite Melts Consequences for the Enrichment and Fractionation of Nb and Ta in the Earths Crust: Contribution to Mineralogy and Petrography,” Vol. 128, No. 2-3, 1997, pp. 213-227. doi:10.1007/s004100050304

[6]   C. M. Scarf, “Viscosity of Apantellerite Melts at One Atmosphere,” Canadian Mineralogist, Vol. 60, 1977, pp. 185-189.

[7]   D. L. Trueman, J. C. Pedersen, L. de St Jorre and D. G. W. Smith, “The Thor Lake Rare-Metal Deposits. Northwest Territories,” In: R. P. Taylor and D. F. Strong, Eds., Recent Advances in the Geology of Granite-Related Mineral Deposits, Canadian Institute of Mining and Metallurgy, Montreal, 1988, pp. 280-290.

[8]   S. Salvi and A. E. Williams-Jones, “The Role of Hydrothermal Processes in Concentrating High-Field Strength Elements in the Lake Strange Peralkaline Complex, Northeastern Canada,” Geochimica et Comsmochimica Acta, Vol. 60, No. 11, 1996, pp. 1917-1932. doi:10.1016/0016-7037(96)00071-3

[9]   P. De Gruyter and T. A. Vogel, “A Model for the Origin of the Alkaline Complexes of Egypt,” Nature, Vol. 291, No. 5816, 1981, pp. 571-574. doi:10.1038/291571a0

[10]   M. Y. Meneisy and M. Y. Volcanicity, In: R. Said, Ed., The Geology of Egypt, A. A. Balkema, Rotterdam, 1990, pp. 157-174.

[11]   M. S. Garson and M. Krs, “Geophysical and Geological Evidence of the Relationship of Red Sea Transverse Tectonics to Ancient Fractures,” Geological Society of America Bulletin, Vol. 87, No. 2, 1976, pp. 169-181. doi:10.1130/0016-7606(1976)87<169:GAGEOT>2.0.CO;2

[12]   R. Black, J. Lameyer and B. Bonin, “The Structural Setting of Alkaline Complexes,” Journal of African Earth Sciences, Vol. 3, No. 1-2, 1985, pp. 5-16.

[13]   P. Bowden, “The Geochemistry and Mineralization of Alkaline Ring Complexes in Africa (A Review),” Journal of African Earth Sciences, Vol. 3, No. 1-2, 1983, pp. 17-39.

[14]   N. L. El Agami and H. M. Abdalla, “Geochemistry of Garra El Hamra Y, Th, REE-Mineralized Peralkaline Granite-Syenite Complex, Southwestern Desert, Egypt. A Metallogenetic Constraint. Egypt,” Min., Vol. 15, 2006, pp. 43-77.

[15]   L. T. D. Conoco-Corporation, “Geological Map of South Western Desert Egypt, 1987, Scale 1:500.000,” Sheet No. NF 53 NV, Gilf Kabeir Plateau, Egyptian General Petroleum Corporation, Cairo, 1987.

[16]   M. E. Issawi, “The Geology of Kurkur Dungul Area,” Egyptian Geological Survey, Paper No. 46, 1968, 102 pp.

[17]   H. Schandelmeier, A. Rich and G. Franz, “Outline of the Geology of Magmatic Units between Gabal Uweinat and Bir Safsaf (SW Egypt/NW Sudan),” Journal of African Earth Sciences, Vol. 1, No. 3-4, 1983, pp. 275-283.

[18]   S. R. Taylor and S. M. McClennan, “The Continental Crust: Its Composition and Evolution,” Blackwell Scientific Publications, Oxford, 1985.

[19]   P. Bowden, “Zirconium in Younger Granites of Northern Nigeria. Geochimica et Comsmochimica Acta, Vol. 30, No. 10, 1966, pp. 985-993. doi:10.1016/0016-7037(66)90113-X

[20]   E. C. T. Chao and M. Fleischer, “Abundace of Zirconium in Igneous Rocks,” 21st International Geological Congress, Norden, Part 1, 1960, pp. 106-131.

[21]   S. R. Taylor, “The Application of Trace Elements Data to Problems in Petrology, Physics and Chemistry of the earth,” Pergamon Press, Oxford, 1965, pp. 1-133.

[22]   A. E. Ringwood, “The Principles Governing Trace Element Behaviour during Magmatic Crystallization. Part II: The Role of Volcanic Rocks,” Geochimica et Comsmochimica Acta, Vol. 7, 1955, pp. 242-254. doi:10.1016/0016-7037(55)90036-3

[23]   G. Calas, “Etude Experimental due Comportement del' Uranium dans les Magmas. Etats d’Oxydation et Coordinance,” Geochimica et Comsmochimica Acta, Vol. 43, No. 9, pp. 1521-1531.

[24]   K. J. Wenrich, “Mineralization of Breccia Pipes in Northern Arizona (abs.),” In: N. A. Bogdanov, Ed., Special Session of the International Lithosphere Programme: 27th International Geological Congress, 1984, pp. 380-381.

[25]   J. R. Haas, E. L. Shock and D. C. Sassani, “Rare Earth Elements in Hydrothermal Systems: Estimates of Standard Partial Molal Thermodynamic Properties of Aqueous Complexes of the Rate Earth Elements at High Pressures and Temperatures,” Geochimica et Comsmochimica Acta, Vol. 59, No. 21, 1995, pp. 4329-4350. doi:10.1016/0016-7037(95)00314-P

[26]   Y. Ni, J. M. Hughes and A. N. Mariano, “Crystal Chemistry of the Monazite and Xenotime Structures,” American Mineralogist, Vol. 80, 1995, pp. 21-26.

[27]   L. A. “Boatner Synthesis, Structure and Properties of Monazite, Pretulite and Xenotime,” Reviews in Mineralogy and Geochemistry, Vol. 48, No. 1, 2002, pp. 87-121. doi:10.2138/rmg.2002.48.4

[28]   V. S. Stubican and R. Roy, High-Pressure Scheelite-Structure Polymorphs of Rare Earth Vanadates and Arsenate,” Zeitschrift für Kristallographie, Vol. 119, No. 1-2, 1963, pp. 90-97. doi:10.1524/zkri.1963.119.1-2.90

[29]   W. Irber, “The Lanthanide Tetrad Effect and Its Correlation with K/Rb, Eu/Eu*, Sr/Eu, Y/Ho and Zr/Hf of Evolving Peraluminous Granite Suites,” Geochimica et Comsmochimica Acta, Vol. 63, No. 3-4, 1999, pp. 489-508. doi:10.1524/zkri.1963.119.1-2.90

[30]   S. A. Elatta, “Occurrence of Rare Metals at Gabal Abu Khruq Area, South Eastern Desert, Egypt,” Ph.D. Thesis, Faculty of Science, Ain Shams University, Cairo, 2007, 74 pp.

[31]   D. R. Baker and J. Vaillancourt, “The Low Viscosities of F + H2O-Bearing Granitic Melts and Implications for Melt Extraction and Transport,” Earth and Planetary Science Letters, Vol. 132, No. 1, 1995, pp. 199-211.

[32]   M. Bau and P. Dulski, “Comparing Yttrium and Rare Earths in Hydrothermal Fluids from the Mid-Atlantic Ridge: Implications for Y and REE Behaviour during Near-Vent Mixing and for the Y/Ho Ratio of Proterozoic Sea Water,” Chemical Geology, Vol. 155, No. 1-2, 1999, pp. 77-90. doi:10.1016/S0009-2541(98)00142-9