Geophysical Mapping, Geochemical Evidence and Mineralogy for Nuweibi Rare Metal Albite Granite, Eastern Desert, Egypt
Ibrahim Gaafar
Nuclear Materials Authority, Cairo, Egypt.
DOI: 10.4236/ojg.2014.44010   PDF   HTML     5,907 Downloads   8,258 Views   Citations


The present study aims to shed light on the rare metals of Nuweibiareaalbite granite in the Eastern Desert through the chemical analyses of the two types of fine-grained albite granite (FAG) and medium-grained albite granite (MAG) in addition to mineralogical studies as well as ground spectrometric survey and aeromagnetic mapping. On the basis of ground spectrometric measurements K, eUand eTh distribution maps were obtained. The concentration of K, U and Th content shows maxima (4.5%, 13 ppm and 27 ppm on average, respectively) in the FAG, and (4.5%, 10 ppm and 35 ppm on average) in the MAG. The eU/eTh ratio significantly increases in FAG with higher magma differentiation than MAG reaching 0.63. This paper uses magnetic geophysical methods to investigate geometry and sense of motion across the Nuweibi area. The interpreted structures from the magnetic maps are characterized by two main intersecting sets of NW-SE and NE-SW trending faults in addition to other three minor faults that trend in N-S, NNW-SSE and ENE-WSW directions. The NW-SE trending faults represent the recent sets in the study area where they are dissected and displaced by the other old faults. The Werner depth map shows the interface depths of the granite and basement rocks that extend to great depths ranging from 10 to 380 m. FAG is extended underneath most of the surrounding schist rocks because of their attributed low magnetic intensity that confirmed also with drilling. Microscope and Microprobe analyses indicated that the most important radioactive minerals include uranothorite, thorite, zircon, and monazite. Columbite group minerals represent the most common Nb-Ta host in Nuweibi-albite granites that contain significant levels of Ta (up to 65.4 wt. % Ta2O5) and Nb (up to 60 wt. % Nb2O5), with Ta/(Ta+Nb) ratio ranging from 0.17 to 0.84. Columbite group minerals are represented mostly by columbite-(Mn) and tantalite-(Mn), with Mn/(Mn+Fe) ratio ranging from 0.42 to 0.89. Ixiolite, wodgnite and tapiolite-(Mn) were found only in the FAG indicating the final stages of the evolution of parental granitic magma. The U-Th and U-K variation diagrams suggested that magmatic processes controlled the distribution of these elements. The Scanning Electron-microprobe analyses reveal variable compositions and extents between the MAG and FAG in the Nb, Ta-Ti, Sn-Fe, Mn triangular plot. It is worthy to be noted that because of the higher Ta/Nb ratio in the tapiolite-Mn and ixiolite of FAG in comparison with the coexisting Mn-columbite in the MAG, levels of HfO2 greater than 15% and even attaining 23%, characterized the hafnium zircon in the Nwueibialbite-enriched facies. There is a close correlation between Hf/(Hf + Zr) and Ta/(Nb + Ta) which seems mainly associated with the FAG.

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Gaafar, I. (2014) Geophysical Mapping, Geochemical Evidence and Mineralogy for Nuweibi Rare Metal Albite Granite, Eastern Desert, Egypt. Open Journal of Geology, 4, 108-136. doi: 10.4236/ojg.2014.44010.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Airo, M.L. and Loukola-Ruskeeniemi, K. (2004) Characterization of Sulfide Deposits by Airborne Magnetic and Gamma-Ray Responses in Eastern Finland. Ore Geology Reviews, 24, 67-84.
[2] Murphy, B.S. (2007) Airborne Geophysics and the Indian Scenario. Journal of Indian Geophysical Union, 11, 1-28.
[3] Telford, W.M., Geldart, L.P. and Sheriff, R.E. (1990) Applied Geophysics. 2nd Edition, Cambridge University Press, Cambridge.
[4] Gaafar, I.M. and Aboelkheir, H.M. (2013) Analysis of Geological and Geophysical Datasets for Radioelement Exploration in Kab Amiri Area, Central Eastern Desert, Egypt. The Open Geology Journal, 7, 1-20.
[5] Armstrong, M. and Rodeghiero, A. (2006) Airborne Geophysical Techniques in Aziz. Coal Operators’ Conference, University of Wollongong and the Australasian Institute Mining and Metallurgy, 113-131.
[6] Kovalenko, V.I. (1978) The Genesis of Rare Metal Granitoids and Related Ore Deposits. In: Stemprok, M., Burnol, L. and Tischendorf, G., Eds., Metallization Associated with Acid Magmatism, Vol. 3, Geological Survey, Prague, 235-247.
[7] Tischendorf, G. (1977) Geochemical and Petrographic Characteristics of Silicic Magmatic Rocks Associated with Rare-Element Mineralization. In: Stemprok, M., Burnol, L. and Tischendorf, G., Eds., Metallization Associated with Acid Magmatism, Czechoslovakia Geological Survey, Prague, 41-98.
[8] Helba, H., Trumbull, R.B., Morteani, G., Khalil, S.O. and Arslan, A. (1997) Geochemical and Petrographical Studies of Ta Mineralization in the Nuweibi Albite Granite Complex, Eastern Desert, Egypt. Mineralium Deposita, 32, 164-179.
[9] Gippsland Ltd. (2007) Annual Report 2007. Gippsland Limited, Perth.
[10] Sabet, A.H. and Tsogoev, V. (1973) Problems of Geological and Economic Evaluation of Tantalum Deposits in Apogranites during Stages of Prospection and Exploration. Annals of Geological Survey, Egypt.
[11] Jahn, S. (1996) Geochemische und mineralogische Untersuchungen zur Metallogenese Seltenmetall-führender Granitoide in der Central Eastern Desert, Agypten. Unpublished Ph.D. Thesis, Technische Universitat Berlin, Berlin, 271.
[12] Renno, A. (1997) Zur Petrogenese der Albitgranite von Abu Dabbab und Nuweibi, Central Eastern Desert, Agypten. Unpublished PhD Thesis, TechnischeUniversitat Berlin, Berlin, 216 p.
[13] Griffis, R.J., Barning, K., Agezo, F.L. and Akosah, F.K. (2002) Gold Deposits of Ghana. Minerals Commission Report.
[14] Aero-Service (1984) Final Operational Report of Airborne Magnetic/Radiation Survey in the Eastern Desert, Egypt. Conducted for the Egyptian General Petroleum Corporation, Aero-Service Division, Houston, Western Geophysical Co., Taxas.
[15] Zhu, J.C., Li, R.K., Li, F.C., Xiong, X.L., Zhou, F.Y. and Huang, X.L. (2001) Topaz-Albite Granites and Rare-Metal Mineralization in the Limu District, Guangxi Province, Southeast China. Mineralium Deposita, 36, 393-405.
[16] RamaRao, J.V., Acharya, R.S., Ram krishna Rao, M.V., Bala Krishna, B. and Sankaram, S.P. (2002) Geophysical Insight into Northern Part of Chitrdurga Schist Belt, Karnataka. GSI Spl. Publications, No. 75, 170-180.
[17] Galbraith, J.H. and Saunders, D.F. (1983) Rock Classification by Characteristics of Areal Gamma-Ray Measurements. Journal of Geochemical Exploration, 18, 49-73. (83)90080-8
[18] Charbonneau, B.W. and Ford, K.L. (1979) Discovery of Two Uranium Occurrences in Paleozoic Sedimentary Rocks at South March, Ontario and South Maitland, Nova Scotia. Journal of the Canadian Society of Exploration Geophysicists, 15, 54-76.
[19] Rudnick, R.L. and Gao, S. (2003) Composition of the Continental Crust. In: Rudnick, R.L., Ed., The Crust, Elsevier-Pergamon, Oxford, 1-64.
[20] Silva, A.M., Pires, A.C., McCafferty, A., Moraes, R. and Xia, H. (2003) Application of Airborne Geophysical Data to Mineral Exploration in the Uneven Exposed Terrains of the Rio Das Velhas Greenstone Belt. Revista Brasileira de Geociências, 33, 17-28.
[21] Henson, P.A., Blewett, R.S., Roy, I.G., Miller, J.M. and Czarnota, K. (2010) 4D Architecture and Tectonic Evolution of the Laverton Region, Eastern Yilgarn Craton, Western Australia. Precambrian Research, 183, 338-355.
[22] Debon, F. and Lefort, P. (1988) A Cationic Classification of Common Plutonic Rocks and Their Magmatic Associations: Principles, Method, Applications. Bulletin de Minéralogie, 111, 493-510.
[23] Dupont, A., Vander Auwera, J., Pin, C., Marincea, S. and Berza, T. (2002) Trace Element and Isotope (Sr, Nd) Geochemistry of Porphyry-and Skarn-Mineralising Late Cretaceous Intrusions from Banat, Western South Carpathians, Romania. Mineralium Deposita, 37, 568-586.
[24] Yu, D.G. and Wang, M. (1988) The Geochemical Characteristics of U and Th in the Granitoid Rocks of Zhuguang-Taoshan Complex Pluton. Journal of East China College of Geology, 11, 301-312.
[25] Sun, S.S. and McDonough, W.F. (1989) Chemical and Isotopic Systematics of Oceanic Basalts: Implications for Mantle Composition and Processes. In: Saunders, A.D. and Norry M.J., Eds., Magmatism in the Ocean Basins, Vol. 42, Geological Society, London, Special Publications, 313-345.
[26] Boynton, W.V. (1984) Cosmochemistry of the Rare Earth Elements: Meteorite Studies. In: Henserson, P., Ed., Rare Earth Element Geochemistry, Elsevier, Amsterdam, 63-114.
[27] Pagel, M. (1981) Acteurs de distribution et de concentration de l’uranium et du Thorium dansquelquesgranities de IachainehercynienneD’Europe. Thesis, Univ. of Nancy I.L in Leroy and Turpin.
[28] Hughes, J.M., Cameron, M. and Mariano, A.N. (1991) Rare-Earth-Element Ordering and Structural Variations in Natural Rare-Earth-Element-Bearing Apatites. American Mineralogist, 76, 1165-1173.
[29] Taylor, R.P. and Fallick, A.E. (1997) The Evolution of Fluorine-Rich Magmas: Source Dichotomy, Magmatic Convergence and the Origins of Topaz Granite. Terra Nova, 9, 105.
[30] Linnen, R.L. and Cuney, M. (2005) Granite-Related Rare-Element Deposits and Experimental Constraints on Ta-Nb-W-Sn-Zr-Hf Mineralization. In: Linnen, R.L. and Samson, I.M., Eds., Rare-Element Geochemistry and Mineral Deposits, Vol. 17, Geological Association of Canada Short Course Notes, 45-68.
[31] Wang, R.C., Fontan, F., Xu, S., Chen, X. and Monchoux, P. (1997) The Association of Columbite, Tantalite and Tapiolite in the Suzhou Granite, China. Canadian Mineralogist, 35, 699-706.
[32] Cerny, P., Meintzer, R.E. and Anderson, A.J. (1985) Extreme Fractionation in Rare-Element Granitic Pegmatites: Selected Examples of Data and Mechanisms. The Canadian Mineralogist, 23, 381-421.
[33] Neiva, A.M.R. (1996) Geochemistry of Cassiterite and Its Inclusions and Exsolution Products from Tin and Tungsten Deposits in Portugal. Canadian Mineralogist, 34, 745-768.

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