Skip to main content
SpringerLink
Log in

Mineralogy and radioactivity of pegmatites from South Wadi Khuda area, Eastern Desert, Egypt

  • Published:
Chinese Journal of Geochemistry Aims and scope Submit manuscript

Abstract

Radioactive minerals in pegmatites associated with granitic rocks are commonly encountered in the south of the Wadi Khuda area and found as dyke-like and small bodies. They are observed within garnet-muscovite granites near the contact with older granitoids. Field surveys indicated that the studied pegmatites vary in dimensions ranging from 2 to 10 m in width and from 10 to 500 m in length. They are composed mainly of intergrowth of milky quartz, reddish-pink K-feldspar and plagioclase together with small pockets of muscovite.

Field radiometric measurements indicated that radioactivity in pegmatites is more than twice that of their enclosing country rocks. Radionuclide measurements revealed that the average contents of U and Th increase gradually from rocks of dioritic to granodioritic composition (1.5×10−6 U and 4.3×10−6 Th) and increase significantly in biotite granites (5.8×10−6 U and 15.2×10−6 Th) but drastically decrease in muscovite granites (2.2×10−6 U and 5.6×10−6 Th). The average contents of U and Th of anomalous pegmatites are 95.3×10−6 and 116.9×10−6, respectively, indicating their uraniferous nature. In the south of the Wadi Khuda area, pegmatites are low in average Th/U (1.4) and high in average U/K (35.6), which suggests that uranium concentrating processes did not affect the pegmatites, indicating poor source-rocks.

Mineralogical investigations of the studied pegmatites revealed the presence of secondary uranium minerals (kasolite and autunite), in addition to zircon, thorite, apatite, garnet and biotite. Primary and secondary radioactive mineralizations indicated that the mineralization is not only magmatic, but also post-magmatic. Electron microprobe analyses showed distinct cryptic chemical zoning within thorite where UO2 decreases from core to rim. This feature in thorite is sporadic, suggesting non-uniform redistributions of UO2 within thorite during magmatic processes.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Abdalla H.M. and El Afandy A.H. (2003) Contrasting mineralogical and geochemical characteristics of two A-type pegmatite fields, Eastern Desert, Egypt [J]. Egyptian Mineralogists. 20, 287–328.

    Google Scholar 

  • Abdel Karim A.M. and E. Arva Sos. (2000) Geochemical characteristics and K-Ar ages of some granitoid from South Eastern Desert, Egypt [J]. Egyptian Journal of Geology. 44/1, 305–318.

    Google Scholar 

  • Abdel Khalek M.L., Takla M.A., Sehim A.A., Abdel wahed M., Hamimi Z., and Sakran Sh.M. (1999) Tectonic evolution of the Shield rocks, East Wadi Beitan area, South Eastern Desert, Egypt [J]. Egyptian Journal of Geology. 43/1, 1–25.

    Google Scholar 

  • Abdel Warith A., Raslan M.F., and Ali M.A. (2007) Mineralogy and Radioactivity of Pegmatite Bodies from the Granitic Pluton of Gabal Um Tager El-Tahtani Area, Central Eastern Desert, Egypt [C]. The 10th International Mining, Petroleum, and Metallurgical Engineering Conference, Mining, Code No. M3, Faculty of Engineering-Assuit University.

  • Adams J.A.S., Osmond J.K., and Rogers J.J.W. (1956) “The geochemistry of thorium and uranium”. In Physics and Chemistry of the Earth [M]. 2, 298–348.

    Google Scholar 

  • Ahmed F.Y. and Abdel Warith A. (2003) Radioactive Studies of Gabal Um Dissi Younger Granites and the Associated Pegmatites, North Eastern Desert, Egypt, Al Azhar Bulletien of Science [C]. pp.25–27, 31–43. Proc. of 5th Int. Sci. Conf.

  • Ali M.A. (2001) Geology, Petrology and Radioactivity of Gabal El-Sibai Area, Central Eastern Desert, Egypt [D]. pp.300. Ph.D Thesis, Cairo University.

  • Ali M.A., Raslan M.F., and El-Feky M.G. (2005) Radioactivity and Mineralogy of Some Pegmatite Bodies from Gabal Al-Farayid Granites, South Eastern Desert, Egypt [C]. The 9th International Mining, Petroleum, and Metallurgical Engineering Conference February 21—24, 2005, Faculty of Engineering-Cairo University.

  • Cerny P. (1990) Distribution, affiliation and derivation of rare-element granite pegmatites in Canadian Shield [J]. Geologische Rundschau. 79, 183–226.

    Article  Google Scholar 

  • Dawood Y.H., Abd El-Naby H.H., and Sharafeldin A.A. (2004) Infuence 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.

    Article  Google Scholar 

  • Deer W.A., Howie R.A., and Zussman J. (1992) Rock Forming Minerals, Vol. 5. Non Silicates [M]. John Wiley and Sons, New York.

    Google Scholar 

  • Dixon T.H. (1981) Age and chemical characteristics of some Pre-Pan-African rocks in the Egyptian shield [J]. Precambrian Res. 14, 119–133.

    Article  Google Scholar 

  • El Aassy I.E., Shazly A.G., Hussein H.A., Heikel M.T.S., and El Galy M.M. (1998) Pegmatites of Nuweiba-Dahab Area, West Gulf of Aqaba, Sinai, Egypt: Field Aspects, Mineralogy, Geochemistry and Radioactivity [C]. pp.139–151. 3rd Conf. of Geoch. Alex. Univ. V.I., Geoch. of igneous rocks and Geochemical exploration, Alex.

  • El-Manharawy M.S. (1977) Geochronological Investigation of Some Basement Rocks in Central Eastern Desert, Egypt Between Lat. 25° and 26°N [D]. pp.216. Unpub. Ph. D. Thesis, Cairo University, Egypt.

    Google Scholar 

  • El-Ramly M.F. and Akaad M.K. (1960) The basement complex in the Central Eastern Desert of Egypt between lat. 24°30′and 25°40′N [J]. Geological. Survey, Egypt. (8), 35.

  • Ford K.L. (1982) Uraniferous pegmatites of the Sharbot Lake area, Ontario. In Uranium in Granites (ed. Maurice Y.T.) [M]. pp.81–23, 125–138. Geol. Surv. of Canada.

  • Erict T.S. (2005) Identification and alteration trends of granitic-pegmatite-hosted (Y, REE, U, Th)-(Nb, Ta, Ti) oxide minerals: A statistical approach [J]. Canadian Mineralogist. 43, 1291–1303.

    Article  Google Scholar 

  • Gaberlman J.W. (1977) Migration of uranium and thorium exploration significance [J]. American Association for Petroleum Geologists Bulletin, Studies in Geology. APPG, USA. (3), 168.

    Google Scholar 

  • Hanson S.L., Simons W.B., and Falster (1998) A.U., Nb-Ta-Ti oxides in granitic pegmatites from the Topsham pegmatite district, South Maine [J]. The Canadian Mineralogist. 36, 601–608.

    Google Scholar 

  • Hassan M.A. and Hashad A.H. (1990) Precambrian of Egypt. The anorogenic alkalic rocks, South Eastern Desert, Egypt [J]. Annal Geological Survery 9, Egypt. 81–101.

  • Hume W.F. (1935) Geology of Egypt. Vol. II, Part II. The Later Plutonic and Intrusive Rocks. Geological Survery Egypt [M]. pp.301–688. Government Press, Cairo.

    Google Scholar 

  • Hussein A.A., Ali M.M., and El-Ramly M.F. (1982) A proposed new classification of the granites of Egypt [J]. Journal of Volcanic and Geothermal Research. 14, 187–198.

    Article  Google Scholar 

  • Ibrahim M.E., Shalaby M.H., and Ammar S.E. (1997) Preliminary studies on some uranium and thorium bearing pegmatites at G. Abu Dob, Central Eastern Desert, Egypt [J]. Proc. Egypt. Acad. Sci. 47, 173–188.

    Google Scholar 

  • Ibrahim M.E., Saleh G.M., and Abd El-Naby H.H. (2001) Uranium mineralization in the two mica granite of Gabal Ribdab, South Eastern Desert, Egypt [J]. Appl. Radiat. Isot. 55/6, 123–134.

    Google Scholar 

  • Matolin M.M. (1991) “Construction and Use of Spectrometric Calibration Pads”, Laboratory of Gamma-ray spectrometry, N.M.A., Egypt [R]. A report to the Government of the Arab Republic of Egypt. Project Egy., 4, 030-03, IAEA.

  • Matsubara S., Kato A., and Matsuyama F. (1995) Nb-Ta minerals in a lithium pegmatite from Myokenzan, Ibaraki Prefecture, Japan [J]. Mineralogical Journal. 17, 338–345.

    Article  Google Scholar 

  • Moussa E.M.M., Stern R.J., Manton W.I., and Ali K.A. (2008) Shrimp zircon dating and Sm/Nd isotopic investigations of Neoproterozoic granitoids, Eastern Desert, Egypt [J]. Precamb. Res. 160, 341–356.

    Article  Google Scholar 

  • Osmond J.K., Dabous A.A., and Dawood Y.H. (1999) U series age and origin of two secondary uranium deposits, central Eastern Desert, Egypt [J]. Economic Geology. 94, 273–280.

    Article  Google Scholar 

  • Page L.R. (1950) Uranium in pegmatites [J]. Econ. Geol. 45, 12–34.

    Article  Google Scholar 

  • Pal D.C., Mishra B., and Bernhardt H.J. (2007) Mineralogy and geochemistry of pegmatite-hosted Sn-, Ta- Nb-, and Zr- Hf-bearing minerals from the southeastern part of the Bastar-Malkangiri pegmatite belt, Central India [J]. Ore Geology Reviews. 30, 30–55.

    Article  Google Scholar 

  • Raslan M.F. (2004) Physical properties of kasolite from Gabal Gattar uranium prospect, North Eastern Desert, Egypt [J]. Jour. Egyp. Mineralogist (in press).

  • Raslan M.F., El Shall H.E., Omar S.A., and Daher A.M. (2010) Mineralogy of polymetallic mineralized pegmatite of Ras Baroud Granite, Central Eastern Desert, Egypt [J]. Journal of Mineralogical and Petrological Sciences. 105(3), 123–134.

    Article  Google Scholar 

  • Rogers J.J.W. and Adams J.A.S. (1969) Uranium and thorium. In Handbook of Geochemistry (ed. Wedepohl K.H.) [M]. VII-3, 92-B-1 to 92-0-8 and 90-B-1 to 90-0-5, Springer Verlag, Berlin.

    Google Scholar 

  • Rogers J.J.W. and Ragland P.C. (1961) Variation of thorium and uranium in selected granitic rocks [J]. Geochim. et Cosmochim. Acta. 25, 99–109.

    Article  Google Scholar 

  • Saunders D.F. (1979) Characterization of uraniferous geochemical provinces by aerial gamma-ray spectrometry [J]. Min. Eng. 31. 1715–1722.

    Google Scholar 

  • Sayyah T.A., Assaf H.S.A., bdel Kader Z.M., Mahdy M.A., and Omar S.A. (1993) New Nb-Ta occurrence in Gebel Ras baroud, Central Eastern Desert [J]. Egyptian Mineralogist. 5, 41–55.

    Google Scholar 

  • Shaw D.M. (1968) A review of K-Rb fractionation trends by covariance analyses [J]. Geochim. et Cosmochim. Acta. 32, 573–600.

    Article  Google Scholar 

  • Shurmann H.M.E. (1966) The Precambrian Along the Gulf of Suez and the Northern Part of the Red Sea [M]. E.J. Brill, Leiden, Netherlands.

    Google Scholar 

  • Simpson P.R., Brown G.C., Plant J., and Ostle D. (1979) Uranium mineralization and granite magmatism in the British Isles [J]. Phil. Trans. R. Soc. London. A.291, 385–412.

    Google Scholar 

  • Stohl F.V. (1974) The Crystal Chemistry of the Uranyl Silicate Minerals [D]. Ph.D. Thesis, The Pennsylvania State University, University Park.

    Google Scholar 

  • Stohl F.V. and Smith D.K. (1974) The Crystal Chemistry of the Uranyl Silicate Minerals [C]. (abstr.) American Crystallographic Association Meeting, Program and Abstracts Ser. 2, 2, 271.

    Google Scholar 

  • Stohl F.V. and Smith (1981) The Crystal Chemistry of the Uranyl Silicate Minerals [M]. Department of Geosciences, the Pennsylvania State University, University Park. Pennsylvania.

    Google Scholar 

  • Stuckless J.S., Nkomo I.T., Wenmer D.B., and Van Trump G. (1984) Geochemistry and uranium favourability of the postorogenic granites of the north-eastern Arabian Shield, Kingdom of Saudi Arabia [J]. Bull Fac. Earth Sci. King Abdel Aziz Univ. 6, 195–209.

    Google Scholar 

  • William S.B., Hanson S.L., and Falster A.U. (2006) Samarskite-Yb: A new species of the samarskite group from the Little Patsy pegmatites, Jefferson County, Colorado [J]. Canadian Mineralogist. 44, 1119–1125.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Nuclear Materials Authority, P.O. Box 530, El Maadi, Cairo, Egypt

    Mohamed F. Raslan, Mohamed A. Ali & Mohamed G. El-Feky

Authors
  1. Mohamed F. Raslan
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Mohamed A. Ali
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Mohamed G. El-Feky
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Mohamed F. Raslan.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Raslan, M.F., Ali, M.A. & El-Feky, M.G. Mineralogy and radioactivity of pegmatites from South Wadi Khuda area, Eastern Desert, Egypt. Chin. J. Geochem. 29, 343–354 (2010). https://doi.org/10.1007/s11631-010-0466-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11631-010-0466-2

Key words

Search

Navigation