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Geophysical and Geochemical Signature of Rare Metal Granites, Central Eastern Desert, Egypt: Implications for Tectonic Environment

Received: 08 June 2015    Accepted: 04 July 2015    Published: 22 September 2015
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Abstract

Magnetic survey is usually used to delineate magnetic-structural lineaments, analyze their relationships to the inherited ductile fabrics and estimate the depth of perturbing body sources, probably granitic intrusions. These were conducted on the total magnetic intensity reduced to the pole map as well as First vertical derivative and Euler deconvolution maps to show various aeromagnetic structural lineaments which were interpreted as fault systems on the interpretation maps. The early deformational event (D1) produced sets of NE-SW striking local and regional fractures and faults. The second deformational event (D2) generated mainly NNW-SSE and NW-SE faults and fractures some of which intersected earlier (D1) structures. At the northern and eastern parts of the study area (D1/D2) intersections are observed. The last event (D3)created NNE-SSW set of fractures and faults brought out by splay of dykes and reactivated some (D1 and D2)fractures and faults. The study area is also characterized by a major, N-S trending, late-stage dyke system that extend through the area. In order to estimate source depths from gridded aeromagnetic data, 3-D Euler deconvolution method was applied. The calculated source depths are in the range of 200 m to 3500 m. The deepest structures are in the ENE-WSW direction and have depths ranging from about 1100 m to 3000 m in the southeastern part of the study area. On the other hand, the network of parallel major structures trending in NNW-SSE direction have a shallow depth of about 700 m. Rare-metal granites of the Central Eastern Desert of Egypt are classified chemically into alkaline to peralkaline and peraluminous granites. They display the typical geochemical characteristics of A-type granites, with high SiO2, Na2O+K2O, Rb, Zr, Nb, Ta, Sn, and Y, and low CaO, MgO, Ba and Sr. The magmatism of the rare metal granites of the Central Eastern Desert are related to anorogenic, within-plate, A-type, subvolcanic setting and emplaced in the extensional tectonic regime along to the inherited ductile fabrics.

DOI 10.11648/j.earth.20150405.12
Published in Earth Sciences (Volume 4, Issue 5, October 2015)
Page(s) 161-179
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This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Rare-Metal Granites, Magnetic Survey, Structural Lineaments

References
[1] Abdalla, H. M., Helba, H. A. and Mohamed, F. H., 1998: Chemistry of columbite-tantalite minerals in rare metal granitoids, Eastern Desert, Egypt. Mineral. Mag. V. 62, N. 6, pp. 821–836.
[2] Abd-Elmeguid, A. A., Ammar, S. E, Ibrahim, T. M. M., Ali, Kh. G., Shahin, H. A., Omar, S. A, Gaafar, I. M., Masoud, S. M., Khamis, A. A., Haridy, M. H., Kamel, A. I., 2003: Uranium potential of Eastern Desert granites, Egypt. Internal Report, (Unpublished) Nuclear Materials Authority, Egypt.
[3] Abd-Elrahman, A. M., and El-Kibbi, M. M., 2001: Anorogenic magmatism: chemical evolution of the Mount El-Sibai A-type complex (Egypt), and implications for the origin of Within- Plate Felsic magmas. Geological Magazine, V. 138, pp. 67–85.
[4] Aero Service, 1984: Final operational report of airborne magnetic/radiation survey in the Eastern Desert, Egypt, Aero Service Division, Houston, Texas, V. 6.
[5] Ali, Kh. G., 2003: Geology and radioactivity of Naba-Nuweibi area, Central Eastern Desert, Egypt. Unpub. Ph. D. Thesis, Ain Shams Univ., Cairo, Egypt, 194 p.
[6] Ali, Kh. G., 2013: The role of inherited ductile fabrics in developing the most favourable structures hosting uranium within the fertile granitic plutons of the Eastern Desert, Egypt. Annals Geol. Surv. Egypt.
[7] Ali, Kh. G., Gaafar, I. M., and Ibrahim, T. M., 2008: Structural control and geophysical signature of Kab Amiri episyenitized muscovite granite and associated uranium showings, Central Eastern Desert, Egypt. Annals Geol. Surv. Egypt. V.XXX, pp. 21-41.
[8] Batchelor, R. A., and Bowden, P., 1985: Petrogenetic interpretation of granitoid rock series using multicationic parameter Chemical Geology, V. 48, pp. 43-55.
[9] Beus, A. A., 1968: Geochemical exploration for endogenic deposits of rare elements on the example of tantalum. Nedra, Muscow, Engl. Transl. GSE Libr, Ottawa, Canada.
[10] Beus, A. A., Severov, V. A., Sitnin, A. A., and Subbotin, K. D., 1962: Albitized and greisenized granites (apogranites): Moscow, Akademiia Nauk SSSR, 196 p. (in Russian).
[11] Cerný, P., 1989: Characteristics of pegmatite deposits of tantalum. In Möller P, Cerný P, Saupé F (eds) Lanthanides, Tantalum and Niobium, SGA Special Publication, Springer-Verlag, Berlin, Germany, V. 7, pp. 192–236
[12] Cerný, P., 1991: Fertile granites of Precambrian rare-element pegmatite fields: is geochemistry controlled by tectonic setting or source lithologies? Precambrian Research, V. 51, pp. 429-468.
[13] Cobbing, J., 2000: The geology and mapping of granite batholiths. Springer-Verlag Berlin Heidelberg, 141 p.
[14] Cuney, M., Marignac C., and Weisbrod, A., 1992: The beauvoirtopazlepidolite-albitegrantie (Massif Central, France) disseminated magmatic Sn-Li-Ta-Nb-Be mineralization. Econ Geol., V. 87, pp.1766–1794.
[15] Debon, F. and Le Fort, P., 1983: Chemical-mineralogical classification of plutonic rocks and associations-Example from southern Asia belts. In: Xu Keqin and Tu Guangchi (eds.), Geology of Granites and their Metallogenetic Relations. Sc. Press, Beijing, pp. 293-311 (Equally in Chinese).
[16] Dobrin, M. B., and Savit, C. H., 1988: Introduction to geophysical prospecting (4th ed.), New York, McGraw-Hill, 867 pp.
[17] Eby, G. N., 1990: The A-type granitoids: A review of their occurrences, chemical characteristics and speculations on their petrogenesis. Lithos, V. 26, pp. 115-134.
[18] Eby, G. N., 1992: Chemical subdivision of the A-type granitoids: petrogenetic and tectonic implications. Geology V. 20, pp. 641–644.
[19] Egyptian Geological Survey and Mining Authority (EGSMA), 1992: Geologic map of Wadi Al-Barramiyah Quadrangle, Egypt.
[20] Fetherston, J. M., 2004: Tantalum in Western Australia. WA Geological Survey, Mineral Resources Bulletin,V. 22, pp. 162.
[21] Frank, M., Torsten, G., Hans-Eike, G., Maria S., Friedhelm, H., Thomas O., Axel, G., and Stijn, D., 2015: Tantalum–(niobium–tin) mineralisation in African pegmatites and rare metal granites: Constraints from Ta–Nb oxide mineralogy, geochemistry and U–Pb geochronology. Ore Geology Reviews, V. 64, pp. 667–719.
[22] Gaafar I. M. (2014): Geophysical Mapping, Geochemical Evidence and Mineralogy for Nuweibi Rare Metal Albite Granite, Eastern Desert, Egypt. Open Journal of Geology, V. 4, pp. 108-136.
[23] Gaafar I. M., 2015: Integration of geophysical and geological data for delimitation of mineralized zones in Um Naggat area, Central Eastern Desert, Egypt. In Press.
[24] Gippsland Ltd., 2007: Annual Report, Gippsland Limited, Perth, Western Australia. http://www.gippslandltd.com.
[25] Govindaraju, K., Mevelle, G., and Chouard, C., 1976: Automated optical emission specto-chemical bulk analyses of silicate rocks with microwave plasma excitation. Anal. Chem., V. 48: pp. 1325-1331.
[26] Greiling, R. O., Kröner, A., El Ramly M. F., Rashwan, A. A. (1988) Structural relationships between the southern and central parts of the Eastern Desert of Egypt: details of a fold and thrust belt. In: El-Gaby, S., Greiling, R. O. The Pan-African belt of Northeast Africa and adjacent areas. Germany, Vieweg publisher, Wiesbaden-Braunschweig, pp.121-146.
[27] Helba, H., Trumbull, R. B., Morteani, G. and Khalil, S. O., 1997: Geochemical and petrographic studies of Ta mineralization in the Nuweibi albite granite complex, Eastern Desert, Egypt. MineraliumDeposita, V. 32, pp. 164-179.
[28] Jeng, Y., Lee, Y. L., Chen, C. Y. and Lin, M. J., 2003: Integrated signal enhancements in magnetic investigation in archaeology. Journal of Applied Geophysics, V. 53, pp. 31–48.
[29] London D., 1987: Experimental phase equilibria in the system LiAlSiO4-SiO2-H2O: a petrogenetic grid for lithium-rich pegmatites. American Mineralogist. V. 69, pp. 995-1004.
[30] Maniar, P. D., and Piccoli, P. M., 1989: Tectonic discrimination of granitoids. Geological Society of Am. Bull., V. 101, pp. 63 5-643.
[31] Murphy, B. S., 2007: Airborne geophysics and the Indian scenario. J. Ind. Geophysics Union, V. 11, No. 1, pp. 1-28.
[32] Nabighian, M. N., 1972: The analytical signal of two-dimensional magnetic bodies with polygonal cross-section, its properties and use for automated anomaly interpretation. Geophysics, V. 37, No.3, pp. 507–517.
[33] Pearce, J. A., Harris, N. B. W. and Tindle, G., 1984: Trace elements discrimination diagram for the tectonic interpretation of granitic rocks. Jour. Petrol., V. 25, pp. 956-983.
[34] Petro, W. L. T., Vogel, T. A., and Willband, J. T., 1979: Major element chemistry of plutonic rocks suites from compressional and extensional plate boundaries. Chemical Geology, V. 20, pp. 217–235.
[35] Pichavant, M., and Manning, D. A. C., 1984: Petrogenesis of tourmaline granites and topaz granites; the contribution of experimental data. Physics of the Earth and Planetary Interiors, V. 35, pp. 31-50.
[36] Plumlee, G., Smith, K. S., Ficklin, W., and Briggs, P. H., 1992: Geological and geochemical controls on the composition of mine drainages and natural drainages in mineralized areas. Proceedings, 7th International Water-Rock Interaction Conference; pp. 419–422. Park City, Utah, USA.
[37] Pollard, P. J., 1989: Geochemistry of granites associated with tantalum and niobium mineralization. In: Moller P, Cerny P, Saupe F (eds) Lanthanides, tantalum and niobium. Springer, Berlin, pp. 145–168
[38] Reid, A. B., Allsop, J. M., Granser, H., Millett, A. J. and Somerton, I. W., 1990: Magnetic interpretation in three dimensions using Euler deconvolution. Geophysics, V. 55, pp. 80–90.
[39] Renno, A. D., Schmidt, W. and Shalaby, I. M., 1993: Rare-metal province Central Eastern Desert, Egypt-II. A-type granites of Abu Dabab, Igla and Nuweibi. In: Thorweihe & Schandelmeier (eds.), Geoscientific Research in Northeast Africa, Balkema, Rotterdam, ISBN, pp. 483-488.
[40] Rickwood, P. C., 1989: Boundary lines within petrologic diagrams which use oxides of major and minor elements. Lithos, V. 22, pp. 247-263.
[41] Roest, W. R., and Pilkington, M., 1993: Identifying remnant magnetization effects on magnetic data. Geophysics, V. 58, pp.653–659.
[42] Sabet, A. H., Tsogoev, V. B., Shibanin, S. P., El-Kadi, M. B., and Awad, S., 1976: The placer deposits of Igla, Abu Dabab and Nuweibi, Ann. Geol. Surv. Egypt, V. 6, pp. 169-180.
[43] Silva, A. M., Pires, A. C., Mc-Cafferty 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, V. 33, No. 2, pp.17-28.
[44] Telford, W. M., Geldard, L. P., Sherriff, R. E., and Keys, D. A., 1990: Applied geophysics. 2nd edition, Cambridge University Press, Cambridge, Great Britain (GB), 860 p.
[45] Thompson, D. T., 1982: EULDPH: A new technique for making computer-assisted depth estimates from magnetic data. Geophysics, V. 47, pp. 31–37.
[46] Vasanthi, A., Sharma, K. K., and Mallick, K. (2006): On new standards for reducing gravity data: The North American gravity database, Geophysics, V. 71, pp. 31–32.
[47] Vauchez, A., Tommasi, A., and Barruol, G. (1998) Rheological heterogeneity, mechanical anisotropy, and tectonics of the continental lithosphere, Tectonophysics, V. 296, pp. 61-86.
[48] Whalen, J. B., Currie, K. L., and Chappell, B. W., 1987: A-type granites: geochemical characteristics, discrimination and petrogenesis. Contrib. Min. Petrol., V. 95, pp. 407-419.
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  • Nuclear Materials Authority, Ibrahim, Egypt

  • Nuclear Materials Authority, Ibrahim, Egypt

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    Ibrahim M. Gaafar, Khaled G. Ali. (2015). Geophysical and Geochemical Signature of Rare Metal Granites, Central Eastern Desert, Egypt: Implications for Tectonic Environment. Earth Sciences, 4(5), 161-179. https://doi.org/10.11648/j.earth.20150405.12

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    Ibrahim M. Gaafar; Khaled G. Ali. Geophysical and Geochemical Signature of Rare Metal Granites, Central Eastern Desert, Egypt: Implications for Tectonic Environment. Earth Sci. 2015, 4(5), 161-179. doi: 10.11648/j.earth.20150405.12

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    Ibrahim M. Gaafar, Khaled G. Ali. Geophysical and Geochemical Signature of Rare Metal Granites, Central Eastern Desert, Egypt: Implications for Tectonic Environment. Earth Sci. 2015;4(5):161-179. doi: 10.11648/j.earth.20150405.12

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  • @article{10.11648/j.earth.20150405.12,
      author = {Ibrahim M. Gaafar and Khaled G. Ali},
      title = {Geophysical and Geochemical Signature of Rare Metal Granites, Central Eastern Desert, Egypt: Implications for Tectonic Environment},
      journal = {Earth Sciences},
      volume = {4},
      number = {5},
      pages = {161-179},
      doi = {10.11648/j.earth.20150405.12},
      url = {https://doi.org/10.11648/j.earth.20150405.12},
      eprint = {https://download.sciencepg.com/pdf/10.11648.j.earth.20150405.12},
      abstract = {Magnetic survey is usually used to delineate magnetic-structural lineaments, analyze their relationships to the inherited ductile fabrics and estimate the depth of perturbing body sources, probably granitic intrusions. These were conducted on the total magnetic intensity reduced to the pole map as well as First vertical derivative and Euler deconvolution maps to show various aeromagnetic structural lineaments which were interpreted as fault systems on the interpretation maps. The early deformational event (D1) produced sets of NE-SW striking local and regional fractures and faults. The second deformational event (D2) generated mainly NNW-SSE and NW-SE faults and fractures some of which intersected earlier (D1) structures. At the northern and eastern parts of the study area (D1/D2) intersections are observed. The last event (D3)created NNE-SSW set of fractures and faults brought out by splay of dykes and reactivated some (D1 and D2)fractures and faults. The study area is also characterized by a major, N-S trending, late-stage dyke system that extend through the area. In order to estimate source depths from gridded aeromagnetic data, 3-D Euler deconvolution method was applied. The calculated source depths are in the range of 200 m to 3500 m. The deepest structures are in the ENE-WSW direction and have depths ranging from about 1100 m to 3000 m in the southeastern part of the study area. On the other hand, the network of parallel major structures trending in NNW-SSE direction have a shallow depth of about 700 m. Rare-metal granites of the Central Eastern Desert of Egypt are classified chemically into alkaline to peralkaline and peraluminous granites. They display the typical geochemical characteristics of A-type granites, with high SiO2, Na2O+K2O, Rb, Zr, Nb, Ta, Sn, and Y, and low CaO, MgO, Ba and Sr. The magmatism of the rare metal granites of the Central Eastern Desert are related to anorogenic, within-plate, A-type, subvolcanic setting and emplaced in the extensional tectonic regime along to the inherited ductile fabrics.},
     year = {2015}
    }
    

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  • TY  - JOUR
    T1  - Geophysical and Geochemical Signature of Rare Metal Granites, Central Eastern Desert, Egypt: Implications for Tectonic Environment
    AU  - Ibrahim M. Gaafar
    AU  - Khaled G. Ali
    Y1  - 2015/09/22
    PY  - 2015
    N1  - https://doi.org/10.11648/j.earth.20150405.12
    DO  - 10.11648/j.earth.20150405.12
    T2  - Earth Sciences
    JF  - Earth Sciences
    JO  - Earth Sciences
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    PB  - Science Publishing Group
    SN  - 2328-5982
    UR  - https://doi.org/10.11648/j.earth.20150405.12
    AB  - Magnetic survey is usually used to delineate magnetic-structural lineaments, analyze their relationships to the inherited ductile fabrics and estimate the depth of perturbing body sources, probably granitic intrusions. These were conducted on the total magnetic intensity reduced to the pole map as well as First vertical derivative and Euler deconvolution maps to show various aeromagnetic structural lineaments which were interpreted as fault systems on the interpretation maps. The early deformational event (D1) produced sets of NE-SW striking local and regional fractures and faults. The second deformational event (D2) generated mainly NNW-SSE and NW-SE faults and fractures some of which intersected earlier (D1) structures. At the northern and eastern parts of the study area (D1/D2) intersections are observed. The last event (D3)created NNE-SSW set of fractures and faults brought out by splay of dykes and reactivated some (D1 and D2)fractures and faults. The study area is also characterized by a major, N-S trending, late-stage dyke system that extend through the area. In order to estimate source depths from gridded aeromagnetic data, 3-D Euler deconvolution method was applied. The calculated source depths are in the range of 200 m to 3500 m. The deepest structures are in the ENE-WSW direction and have depths ranging from about 1100 m to 3000 m in the southeastern part of the study area. On the other hand, the network of parallel major structures trending in NNW-SSE direction have a shallow depth of about 700 m. Rare-metal granites of the Central Eastern Desert of Egypt are classified chemically into alkaline to peralkaline and peraluminous granites. They display the typical geochemical characteristics of A-type granites, with high SiO2, Na2O+K2O, Rb, Zr, Nb, Ta, Sn, and Y, and low CaO, MgO, Ba and Sr. The magmatism of the rare metal granites of the Central Eastern Desert are related to anorogenic, within-plate, A-type, subvolcanic setting and emplaced in the extensional tectonic regime along to the inherited ductile fabrics.
    VL  - 4
    IS  - 5
    ER  - 

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