Skip to main content
SpringerLink
Log in

Dike rock generation and magma interactions in the Bir Safsaf igneous complex, south-west Egypt: Implications for the Pan-African evolution in north-east Africa

  • Published:
Geologische Rundschau Aims and scope Submit manuscript

Abstract

The geological setting, ages, petrography and geochemistry of late Pan-African (≈ 580 Ma) calc-alkaline and tholeiitic dike rocks in the Bir Safsaf igneous complex of south-west Egypt are discussed. These basaltic to rhyolitic dikes intruded contemporaneously and shortly after the intrusion of granitoids. The major and trace element data, Sr and Nd isotope relations, in combination with textural observations, confirm complex interactions between most of the intermediate calcalkaline dike melts and plutonic melts, with different degrees of mixing, assimilation, replenishment and tapping of magma chambers. Trachytic and rhyolitic dikes are strongly differentiated melts from the granitic pluton. The tholeiitic dikes evolved dominantly by fractional crystallization processes. It is inferred that open system and closed system processes operated in calc-alkaline magma chambers, and that the calc-alkaline melts came from a garnet-and amphibole-bearing mantle, modified by a subduction component. Tholeiitic rocks were formed later by fractional crystallization and assimilation processes. Magma ascent of both dike types took place in an extensional environment and the presumed subduction zone has to be seen in connection with the Atmur-Delgo suture zone.

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

  • Bernau R, Darbyshire DPF, Franz G, Harms U, Huth A, Mansour N, Pasteels P, Schandelmeier H (1987) Petrology, geochemistry and structural development of the Bir Safsaf-Aswan uplift, Southern Egypt. J Afr Earth Sci 6: 79–90.

    Google Scholar 

  • Beyth M, Peltz S (1992) Petrology and major-element geochemistry of dikes at Har Timna, Southern Israel. Geol Surv Isr Rep No GSI/13/92: 39 pp.

  • Blundy JD, Shimizu N (1991) Trace element evidence for plagioclase recycling in talc-alkaline magmas. Earth Planet Sci Lett 102: 178–197.

    Google Scholar 

  • Boynton WV (1984) Cosmochemistry of the rare earth elements: Meteorite studies. In: Henderson P (ed) Rare Earth Element Geochemistry. Elsevier, Amsterdam Oxford New York Tokyo, pp 63–114.

    Google Scholar 

  • Briqueu L, Bougault H, Joron JL (1984) Quantification of Nb, Ta, Ti and V anomalies in magmas associated with subduction zones: petrogenetic implications. Earth Planet Sci Lett 68: 297–308.

    Google Scholar 

  • Burkhardt T, Brasse H, Fiedler-Volmer R, Kalkbrenner M, Radic T, Schulz-Ohlberg J (1987) Geophysical investigations of local tectonic problems in SW-Egypt and NW-Sudan. Berl Geowiss Abh (A) 75: 927–967.

    Google Scholar 

  • Cox KG (1988) Numerical modelling of a randomized RTF magma chamber: a comparison with continental flood basalt sequences. J Petrol 29: 681–697.

    Google Scholar 

  • Denkler T, Franz G, Schandelmeier H, Darbyshire DPF, Harms U, Pilot J (1993) Evolution of the south-western part of the Atmur-Delgo suture. In: Thorweihe U, Schandelmeier H (eds) Geoscientific Research in Northeast Africa. Balkema, Rotterdam Brookfield, pp 87–89.

    Google Scholar 

  • Faure G (1986) Principles of Isotope Geology. Wiley, New York Chichester Brisbane Toronto Singapore, 589 pp.

    Google Scholar 

  • Fitton JG, James D, Kempton PD, Ormerod DS, Leeman WP (1988) The role of lithospheric mantle in the generation of Late Cenozoic Basic Magmas in the Western United States. J Petrol Spec Vol: 331–349.

  • Frisch W, Raab D (1987) Early Palaeozoic back-arc and island-arc settings in greenstone sequences of the central Tauern Window (Eastern Alps). Jb Geol BA 129: 545–566.

    Google Scholar 

  • Friz-Töpfer A (1991) Geochemical characterization of Pan-African dike swarms in southern Sinai: from continental margin to intraplate magmatism. Precambrian Res 49: 281–300.

    Google Scholar 

  • Green DH, Ringwood AE (1967) The genesis of basaltic magmas. Contrib Mineral Petrol 15: 103–190.

    Google Scholar 

  • Green TH, Watson, EB (1982) Crystallization of apatite in natural magmas under high pressure, hydrous conditions, with particular reference to ‘orogenic’ rock series. Contrib Mineral Petrol 79: 96–105.

    Google Scholar 

  • Greiling RO, Rashwan AA, El Ramly MF, Kamal El Din GM (1993) Towards a comprehensive structural synthesis of the (Proterozoic) Arabian-Nubian Shield in E-Egypt. In: Thorweihe U, Schandelmeier H (eds) Geoscientific Research in Northeast Africa. Balkema, Rotterdam Brookfield, pp 15–19.

    Google Scholar 

  • Hanson GN (1980) Rare earth elements in petrogenetic studies of igneous systems. Annu Rev Earth Planet Sci 8: 371–406.

    Google Scholar 

  • Harms U (1989) Krustenentwicklung in Nordost-Africa: geochemische und isotopengeochemische Untersuchungen von Granitoiden aus Südägypten and Nordsudan. Berl Geowiss Abh (A) 108: 152 pp.

  • Harms U, Schandelmeier H, Darbyshire DPF (1990) Pan-African reworked early/middle Proterozoic crust in NE Africa west of the Nile: Sr and Nd isotope evidence. J Geol Soc London 147: 859–872.

    Google Scholar 

  • Harms U, Darbyshire DPF, Denkler T, Hengst M, Schandelmeier H (1994) Evolution of the Neoproterozoic Delgo suture zone and crustal growth in Northern Sudan: geochemical and radiogenic isotope constraints. Geol Rundsch 83: 591–603.

    Google Scholar 

  • Harris NBW Hawkesworth CJ, Ries AC (1984) Crustal evolution in northeast and east Africa from model Nd ages. Nature 309: 773–776.

    Google Scholar 

  • Hildreth W, Moorbath S (1988) Crustal contributions to arc magmatism in the Andes of Central Chile. Contrib Mineral Petrol 98: 455–489.

    Google Scholar 

  • Huppert HE, Sparks RSJ (1985) Cooling and contamination of mafic and ultramafic magmas during ascent through continental crust. Earth Planet Sci Lett 74: 371–386.

    Google Scholar 

  • Huth A, Franz G (1988) Structural development of the Precambrian basement in the Bir Safsaf-Aswan area, SW-Egypt. Geol Rundsch 77: 439–452.

    Google Scholar 

  • Irvine TN, Bargar WRA (1971) A guide to the chemical classification of the common volcanic rocks. Can J Earth Sci 8: 523–548.

    CAS  Google Scholar 

  • Kay RW Gast PW (1973) The rare earth content and origin of alkali-rich basalts. J Geol 81: 653–682.

    Google Scholar 

  • Klerkx J (1980) Age and metamorphic evolution of the basement complex around Jabal al Awaynat. In: Salem MJ, Busrewil MT (eds) The Geology of Libya, 3. Academic Press, London, pp 901–906.

    Google Scholar 

  • Klerkx J, Deutsch S (1977) Résultats preliminaires obtenus par la méthode Rb/Sr sur Page des formations précambriennes de la region d'Uweinat (Libye). Mus Roy Afr Centr Dept Géol Min Rapp Ann 1976: 83–94.

    Google Scholar 

  • Klewin WK, Shirey BS (1992) The igneous petrology and magmatic evolution of the Midcontinent rift system. Tectonophysics 213: 33–40.

    Google Scholar 

  • Kröner A (1979) Pan-African plate tectonics and its repercussions on the crust of northeast Africa. Geol Rundsch 68: 565–583.

    Google Scholar 

  • Le Bas MJ, Le Maitre RW, Streckeisen A, Zanettin B (1986) A chemical classification of volcanic rocks based on the total alkali-silica diagram. J Petrol 27: 745–750.

    Google Scholar 

  • Lopez-Escobar L (1984) Petrology and chemistry of volcanic rocks of the Southern Andes. In: Harmon RS, Barreiro BA (eds) Andean Magmatism-Chemical and Isotopic Contraints. Shiva, Cheshire, pp. 47–71.

    Google Scholar 

  • Miyashiro A (1975) Classification, characteristics and origin of ophiolites. J Geol 83: 249–281.

    Google Scholar 

  • Norman MD, Leeman WP (1989) Geochemical evolution of Cenozoic-Cretaceous magmatism and its relation to tectonic settings, southwestern Idaho, U.S.A. Earth Planet Sci Lett 94: 78–96.

    Google Scholar 

  • O'Callaghan LJ, Francis PW (1986) Volcanological and petrological evolution of San Pedro volcano, Provincia El Loa, North Chile. J Geol Soc London 143: 275–286.

    Google Scholar 

  • O'Hara MJ, Mathews RE (1981) Geochemical evolution in an advancing, periodically replenished, periodically tapped, continously fractionated magma chamber. J. Geol Soc London 138: 237–277.

    Google Scholar 

  • Perfit MR, Gust DA, Bence AE, Arculus RJ, Taylor SR (1980) Chemical characteristics of island-arc basalts: implications for mantle sources. Chem Geol 30: 227–256.

    Article  CAS  Google Scholar 

  • Pudlo D (1993) Komplexe Differentiationsprozesse in Magmenkammersystemen — Petrogenese der panafrikanischen Ganggesteine im Granitoidpluton von Bir Safsaf/SW-Ägypten. PhD Thesis. Technical University Berlin, 211 pp.

  • Richter A (1986) Geologie der metamorphen und magmatischen Gesteine im Gebiet zwischen Gebel Uweinat and Gebel Kamil, SW-Ägypten/NW-Sudan. Berl Geowiss Abh (A) 73: 201 pp.

  • Saradeth S, Soffel HC, Horn P, Müller-Sohnius D, Schult A (1989) Intracambrian and Phanerozoic pole positions and potassium-argon ages from the East Sahara Craton. Geophys J 97: 209–221.

    Google Scholar 

  • Saunders AD, Norry MJ, Taney J (1988) Origin of MORB and chemically-depleted mantle reservoirs: trace element constraints. J Petrol Spec Vol: 415–445.

  • Schandelmeier H, Darbyshire F (1984) Metamorphic and magmatic events in the Uweinat-Bir Safsaf Uplift (Western Desert/Egypt). Geol. Rundsch 73: 819–831.

    Google Scholar 

  • Schandelmeier H, Huth A, Harms U, Franz G, Bernau R (1987) The East Saharan Craton in Egypt and northern Sudan: lithology, metamorphism, magmatism, geochronology and structural development. Berl Geowiss Abh (A) 75: 25–48.

    Google Scholar 

  • Schandelmeier H, Wipfler E, Küster D, Sultan M, Becker R, Stern RJ, Abdelsalam MG (1994). The Atmur-Delgo suture: a Neoproterozoic oceanic basin extending into the interior of North Africa. Geology 22: 563–566.

    Google Scholar 

  • Stamatelopoulou-Seymour K, Vlassopoulos D, Pearce TH, Rice C (1990) The record of magma chamber processes in plagioclase phenocrysts at Thera Volcano, Aegan Volcanic Arc, Greece. Contrib Mineral Petrol 104: 73–84.

    CAS  Google Scholar 

  • Stern RJ, Sellers G, Gottfried D (1988) Bimodal dike swarms in the north eastern desert of Egypt: significance for the origin of Late Precambrian ‘A-Type’ granites in northern Afro-Arabia. In: El Gaby S, Greiling RO (eds) The Pan-African Belt of Northeast Africa and Adjacent Areas. Vieweg, Braunschweig Wiesbaden, pp 147–180.

    Google Scholar 

  • Sultan M, Tucker RD (1994) U-Pb (zircon) ages for the gneissic terrane west of the Nile, Southern Egypt. Geol Rundsch 83: 514–522.

    Google Scholar 

  • Tatsumi Y, Murasaki M, Nohda S (1992) Across-arc variations of lava chemistry in the Izu-Bonin Arc: identification of subduction components. J Volcanol Geotherm Res 49: 179–190.

    Google Scholar 

  • Voshage H, Hofmann AW, Mazzucchelli M, Rivalenti G, Sinigoi S, Raczek I, Demarchi G (1990) Isotopic evidence from the Ivrea Zone for a hybrid lower crust formed by magmatic underplating. Nature 347: 731–736.

    Google Scholar 

  • Wallbrecher E, Fritz H, Khudeir AA, Farahad F (1993) Kinematics of Pan-African thrusting and extension in Egypt. In: Thorweihe U, Schandelmeier H (eds) Geoscientific Research in Northeast Africa. Balkema, Rotterdam Brookfield, pp 27–30.

    Google Scholar 

  • Wilson M (1989) Igneous petrogenesis — A Global Tectonic Approach. Unwin Hyman, London Boston Sydney Wellington, 466 pp.

    Google Scholar 

  • Wood DA, Joron JL, Treuil M, Norry M, Tarney J (1979) Elemental and Sr Isotope Variations in basic lavas from Iceland and the Surrounding ocean floor. Contrib Mineral Petrol 70: 319–339.

    CAS  PubMed  Google Scholar 

  • Wörner G, Harmon RS, Davidson J, Moorbath S, Turner DL, McMillan N, Nye C, Lopez-Escobar L, Moreno H (1988) The Nevados de Payachata volcanic region (18OS/69OW N-Chile) — I. Geological, geochemical, and isotopic Observations. Bull Volcanol 50: 287–303.

    Google Scholar 

  • Yagi K, Takeshita H (1987) Impact of hornblende crystallization for the genesis of calc-alkalic andesites. In: Myen BO (ed) Magmatic Processes: Physiochemical Principles. Geochem See Spec Pub 1: 183–190.

Download references

Author information

Authors and Affiliations

  1. Fachgebiet Petrologie, Technische Universität Berlin, Strasse des 17. Juni 135, D-10623, Berlin, Germany

    D. Pudlo & G. Franz

Authors
  1. D. Pudlo
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. G. Franz
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Pudlo, D., Franz, G. Dike rock generation and magma interactions in the Bir Safsaf igneous complex, south-west Egypt: Implications for the Pan-African evolution in north-east Africa. Geol Rundsch 83, 523–536 (1994). https://doi.org/10.1007/BF00194159

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00194159

Key words

Search

Navigation