Abstract
Altered granite occurrences (GII and GV) at Gabal (G.) Gattar are the most important mineralized rocks hosting U-mineralization in Egypt. This mineralized granite is affected by multi-stage hydrothermal alteration processes along brittle structures. This alteration comprises pre-ore alkali-metasomatism and ore-stage hydrothermal hematitization, silicification, kaolinitization, fluoritization, carbonatization and episyenitization. Autoradiographic examination indicates that primary uranium mineralization is present as massive or disseminated ores along tectonic fractures, interstitially in granular minerals, and as cements of breccias. Uraninite, pitchblende and coffinite are the main primary minerals, while uranophane and kasolite are the secondary ones. Galena, chalcopyrite, pyrrohtite and pyrite are the most abundant sulphides in association with uranium mineralizations. Hydrothermal alterations at the GII occurrence exhibit an increase in Ni, Cu, Zn, Pb, Mo, Nb, Rb beside HREEs and a decrease in Ba, Co, Sr, and V, while alterations at the GV occurrence show enrichment in Ni, Cu, Pb, Mo, Nb, Y, HREEs and depletion in Zn, Ba, Co, Rb, Sr, and V. Hydrothermal alteration during the late magmatic stage is also identified through the development of unusual REE patterns and fractionation of ratios like Zr/Hf and Y/Ho out of the CHARAC (Charge Radius Controlled) range. Non-chondritic Y/Ho ratio at GV is of larger value than chondritic one which may result from water-rock interaction or print from the encompassing sedimentary rocks. Fluid inclusion studies on quartz and fluorite revealed that temperatures of the mineralizing fluids range between 126 and 240°C at pressure ⩽0.5×108 Pa and give salinity values ranging between 1 wt% and 7.8 wt% NaCl equivalent.
Similar content being viewed by others
References
Abdalla H.M. (2001) Geochemistry and origin of rare metal mineralization of Um Safi felsite, Centeral Eastern Dessert, Egypt [J]. Egyp. Jour. Geol. 45(1A), 131–149.
Abd El-Wahed A.A., Ammar S.E., Youssief T.F., and El-Husseiny M.O. (2002) Petrography, REE geochemistry and Rb-Sr isotopes study of Abu Tiyur granite, Central Eastern Desert, Egypt. M.E.R.C. Ain Shams University [J]. Earth Science Ser. 16, 16–24.
Abla A.A.R., El Kholy D.M., and Ayoub R.R. (2005) Geological, petrochemical and radiometrical studies of the Pan African late proterozoic rocks, in Wadi Elgammalyia Area, Northern Eastern Desert, Egypt [C]. The fourth International Conference on the Geology of Africa. F. Sci-Assiut Univ. 2, 355–385.
Alexandre P. and Kyser T.K. (2005) Effects of cationic substitutions and alteration in uraninite, and implications for the dating of uranium deposits [J]. Can. Miner. 43, 1005–1017.
Baker J. Ronald (2003) FLUIDS, Package of Computer Programs for Fluid Inclusion Studies [Z]. Program 1: BULK, version 01/03.
Bau M. and Dulski P. (1995) Comparative study of yttrium and rare earth elements behaviors in fluorine-rich hydrothermal fluids [J]. Contrib. Mineral. Petrol. 119, 213–223.
Bau M. (1996) Controls on the fractionation of isovalent trace elements in magmatic and aqueous systems: evidence from Y/Ho, Zr/Hf, and lanthanide tetrad effect [J]. Contrib. Mineral. Petrol. 123, 323–333.
Biddau R., Cidu R., and Frau F. (2002) Rare earth elements in waters from the albitite-bearing granodiorites of Central Sardinia, Italy [J]. Chem. Geol. 182, 1–14.
Bodnar R.J. (1993) Revised equation and stable for determining the freezing point depression of H2O-NaCl solutions [J]. Geochim. et Cosmochim. Acta. 57, 683–684.
Boulvais P., Ruffet G., Cornichet J., and Mermet M. (2007) Cretaceous albitization and dequartzification of Hercynian peraluminous granite in the Salvezines Massif (French Pyrénées) [J]. Lithos. 93, 89–106.
Braun J.J., Viers J., Dupre B., Polve M., Ndam J., and Muller J.P. (1998) Solid/liquid REE fractionation in the lateric system of Goyoum, East Cameroon: The implication for the present dynamics of the soil covers of the humid tropical regions [J]. Geochim. et Cosmochim. Acta. 62, 273–299.
Cerny P., Meintzer R.E., and Anderson A.J. (1985) Extreme fractionation in rare-element granitic pegmatites: Selected examples of data and mechanism [J]. Canad. Mineral. 23, 381–421.
Chary B. and Pollard P.J. (1989) Albite-rich silica-depleted metasomatic rocks at Emuford, northeast Queensland: Mineralogical, geochemical, and fluid inclusion constraints on hydrothermal evolution and tin mineralization [J]. Econ. Geol. 84, 1850–1874.
Condie K.C. (1993) Chemical composition and evolution of the upper continental crust: Contrasting results from surface samples and shales [J]. Chem. Geol. 104, 1–37.
Dawood Y.H. (1998) Isotope Geochemistry of Secondary Ore Deposits and Associated Groundwater, El-Atshan, El-Erediya and El-Missikat Areas, Central Eastern Desert, Egypt [D]. pp.323. Ph. D. Thesis, Ain Shams University.
Dawood Y.H. and Abdel-Naby H.H. (2001) Mineralogy and genesis of secondary uranium deposits, Um Ara area, south Eastern Desert, Egypt [J]. J. Afr. Earth Sci. 32, 317–323.
Dawood Y.H., Abd El-Naby H.H., and Sharafeldin A.A. (2004) Influence of the alteration processes on the origin of uranium and europium anomalies in trachyte, central Eastern Desert, Egypt [J]. J. Geochem. Explor. 88, 15–27.
Dostal J. and Chatterjee A.K. (2000) Contrasting behavior of Nb/Ta and Zr/Hf ratios in a peraluminous granitic pluton (Nova Scotia, Canada) [J]. Chem. Geol. 163, 207–218.
Ekwere S.J. (1985) Li, F and Rb contents and Ba/Rb and Rb/Sr ratios as indicators of post-magmatic alteration and mineralization in the granitic rocks of the Banke and Ririwai younger granite complexes, North Nigeria [J]. Mineral Deposita. 20, 89–93.
El Afandy A.H., Abdalla H.M., and Ammar F. (2000) Geochemistry and radioactive potentiality of Um Naggat Apogranite, Central Eastern Desert, Egypt [J]. Res. Geol. 50, 39–51.
El-Feky M.G., Roz M.E., and El-Galy M.M. (2004) Occurrence of Primary Uranium Mineralizations at G-II, Gabal Gattar Prospect, NED, Egypt [R]. Internal Report, N.M.A.
El-Kammar A.M., Salman A.E., Shalaby M.H., and Mahdy A.I. (2001) Geochemical constraints on rare metals mineralization at the central Eastern Desert of Egypt [J]. Geochem. J. 35(2), 117–135.
El Rakaiby M.L. and Shalaby M.H. (1992) “Geology of Gabal Gattar batholith, central Eastern Desert, Egypt” [J]. Int. J. of Remote Sensing. 13(12), 2337–2347.
El-Sayed M.M., Shalaby M.H., and Hassanen M.A. (2003) Petrological and geochemical constrains on the tectonomagmatic evolution of the late Neoproterozoic granitoids suites in Gattar area, North Eastern Desert, Egypt [J]. N. Jb. Miner. Abh. 178, 239–275.
Fayek M., Jensen K.A., Ewing R.C., and Riciputi L.R. (2002) In-situ isotope analysis of uraninite microstructures from the Oklo-Okélobondo natural fission reactors, Gabon [J]. MRS Symp. Proc. 713, 849–856.
Finch R. and Murakami T. (1999) Systematic and paragenesis of uranium minerals. In Uranium: Mineralogy, Geochemistry and the Environment (eds. Burns and Finch) [J]. Reviews in Mineralogy. 38, 91–179.
Gieré R. (1996) Formation of rare earth minerals in hydrothermal systems. In Rare Earth Minerals: Chemistry, Origin and Ore Deposits (eds. Jones A.P., Walls F., and Williams C.T.) [J]. Mineral Soc. Ser. 7, 105–150.
Gouveia M.A., Prude’ncio M.I., Figueiredo M.O., Pereira L.C.J., Waerenborgh J.C., Morgado I., Pena T., and Lopes A. (1993) Behavior of REE and major elements during weathering of granitic rocks, E’vora, Portugal [J]. Chem. Geol. 107, 293–296.
Grant J.A. (1986) The isocon diagram—A sample solution to Gresens’ equation for metasomatic alteration [J]. Econ. Geol. 81, 1976–1982.
Helmy H.M. (1999) Mineralogy, Fluid Inclusion and Geochemistry of Molybdenum-uranium-fluorite Mineralization, Gabal Gattar Area, Eastern Desert, Egypt [C]. 4th International Conf. on Geochemistry. Alexandria University, Egypt, 15–16 Sept. 1999: 171–188.
Henderson P. (ed) (1984) Rare Earth Element Geochemistry [M]. pp.510. Elsevier Science Publications, New York.
Hermann A.G. (1970) Yttrium and lanthanides. In Handbook of Geochemistry (ed. Wedepohl), pp.39–57. Sprin. New York.
Hetcht L., Thuro K., Plinninger R., and Cuney M. (1999) “Mineralogical and geochemical characteristics of hydrothermal alteration and epysyenitization in the Konigshain granites, Northern Bohemian Massif, Germany” [J]. Int. J. Earth Sci. 88, 236–252.
Hussein H.A. and Sayyah T.A. (1992) Uranium Potential of the Younger Granites of Egypt [Z]. International Atomic Energy Agency, Vienna.
Irber W. (1999) The lanthanide tetrad effect and its correlation with K/Rb, Eu/Eu*, Sr/Eu, Y/Ho, and Zr/Hf of evolving peraluminous granite suites [J]. Geochim. et Cosmochim. Acta. 63, 489–508.
Jahn B., Wu F., Capdevila R., Martineau F., Zhao Z., and Wang Y. (2001) Hihly evolved juvenile granites with tetrad REE patterns: The Woduhe and Baerzhe granites from the Great Xing’an Mountains in NE China [J]. Lithos. 59, 171–198.
Jiashu R. and Zehong H. (1982) Forms of Uranium occurrence and its distribution in uraniferous granites. In Geology of Granites and Their Metallogenetic Relations [M]. pp.621–635. Sciences Press, Beijing.
Johannesson K.H., Stetzenbach K.J., and Hodge V.F. (1997) Rare earth elements as geochemical tracers of regional groundwater mixing [J]. Geochim. et Cosmochim. Acta. 61(17), 3605–3618.
Langmuir D. (1978) Uranium solution-mineral equilibria at low temperatures with applications to sedimentary ore deposits [J]. Geochim. et Cosmochim. Acta. 42, 547–567.
London D. (1987) Internal differentiation of rare-element pegmatites: Effect of boron, phosphorus and fluorine [J]. Geochim. et Cosmochim. Acta. 51, 403–420.
Mahdy A.I. (1998) Petrological and Geochemical Studies on Younger Granites and Hammamat Sediments at Gatter-5 Uranium Occurrence, Wadi Balih, North Eastern Desert, Egypt [D]. pp.250. Ph.D. Ain Shams University.
Mahdy A.I. and El-Kammar A.M (2003) Geochemical Partitioning of Isovalent and Tetrad Effect of REE Associating Episynitization of Kab Amiri Granites, Central Eastern Desert of Egypt [C]. pp.111–125. 5th In. Comf. of Geology of Middle EastCairo Egypt.
McLennan S.M. and Taylor S.R. (1979) Rare earth elements mobility associated with uranium mineralization [J]. Nature. 282, 247–250.
Min M.-Z., Luo X.-Z, Du G.-S., He B.-A., and Campbell A.R. (1999) Mineralogical and geochemical constraints on the genesis of the granite-hosted Huangao uranium deposit, SE China [J]. Ore Geol. Rev. 14, 105–127.
Min M., Fanga C., and Fayek M. (2005) Petrography and genetic history of coffinite and uraninite from the Liueryiqi granite-hosted uranium deposit, SE China [J]. Ore Geol. Rev. 26, 187–197.
Osmond J.K., Dabous A.A., and Dawood Y.H. (1999) Uranium series age and origin of two secondary uranium deposits, Central Eastern Desert, Egypt [J]. Econ. Geol. 94, 273–280.
Rodder (1984) Fluid Inclusions: Reviews in Mineralogy [Z]. V. 12, Washington, D.C., Mineralogical Society of America.
Roz M.E. (1994) Geology and Uranium Mineralization of Gabal Gattar, North Eastern Desert, Egypt [D]. pp.175. Unpublished M. Sc. Thesis, Faculty of Science, Cairo University.
Sadek A.A. (2005) Geology, Geochemistry and Radioactivity of Abu Fahm Area With Special Emphasis on the Granitic Rocks, Central Eastern Desert, Egypt [D]. pp.362. Ph. D. Cairo University, Egypt.
Salem H.A. (2004) Geochemical, mineralogical and genesis of hydrothermal uranium mineralizations hosted by late Pan-African magmatism North Eastern Desert, Egypt [J]. Annals Geol. Surv. Egypt. VXXVII, 225–280.
Salman A.B., Shalaby M.H., and Nosseir L.M. (1994) Gabal Gattar uranium province North. Red Sea hills, Egypt [J]. Int. Earth Sci. Congr. Regions. 1, 89–101.
Shalaby M.H. (1996) Structural controls of uranium mineralization of Gabal Qattar, north Eastern Desert, Egypt [J]. Proc. Egypt. Acad. Sci. 46, 521–536.
Shalaby M.H. (1996) Structural controls of uranium mineralization of Gabal Qattar, North Eastern Desert, Egypt [J]. Proc. Egypt. Acad. Sci. 46, 521–536.
Stemprok M. (1979) Mineralized granites and their origin [J]. Episodes. 3, 20–24.
Takahashi Y., Yoshida H., Sato N., Hama K., Yusa Y., and Shimizu H. (2002) W- and M-type tetrad effects in REE patterns for water-rock systems in the Tono uranium deposit, central Japan [J]. Chem. Geol. 184, 311–335.
Wilson M. (1989) Igneous Petrogenesis, A Global Tectonic Approach [M]. Chapman & Hall, London.
Zhang J., Amakawa H., and Nozaki Y. (1994) The comparative behaviors of yttrium and lanthanides in seawater of the North Pacific [J]. Geophys. Res. Lett. 21, 2677–2680.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
El-Feky, M.G. Mineralogical, REE-geochemical and fluid inclusion studies on some uranium occurrences, Gabal Gattar, Northeastern Desert, Egypt. Chin. J. Geochem. 30, 430–443 (2011). https://doi.org/10.1007/s11631-011-0529-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11631-011-0529-z