Skip to main content
SpringerLink
Log in

Late Neoproterozoic Dokhan volcanics, around G. Esh, North Eastern Desert, Egypt: geochemistry and relation of K2O and Nb abundances with crustal thickness

  • Original Paper
  • Published:
Arabian Journal of Geosciences Aims and scope Submit manuscript

Abstract

The Dokhan volcanics outcropping around G. Esh granite form a moderate relief and covers an area of about 40 km2. They are thermally metamorphosed along their contact with the pink granite (Y.G) giving cordierite and sillimanite hornfelses. Two groups are identified; the oldest is basic and predominate at the east of the map area, while the youngest one is mainly intermediate to acidic. The basic rocks are composed of basalt, basaltic andesite, and andesite. They exhibit trachytic, porphyritic, and amygdaloidal textures. Tuffacious varieties are present. The acidic rocks comprise dacitic andesite, porphyritic dacite, rhyodacite, and their equivalent tuffs and ignimbrites. The tuffs are laminated and thinly bedded forming thick belts. The phenocrysts are mainly of quartz, orthoclase, sanidine, and plagioclase and rarely pyroxene. Magnetite is common in the basic varieties while hematite predominates in the acidic rocks. The basic group is low-K tholeiitic to calc-alkaline nature while the acidic one is calc-alkaline and medium-K nature. The two groups have Zr/Y ratios more or less constant suggesting the same magma source. They are higher in Pb, Zn, Ba, Rb, and Sr than island-arc volcanic rocks and lower in K and Nb. The study rocks are more or less comparable to SVZ of Andes (thin continental crust). The relations of K2O and Nb abundances with the crustal thickness are discussed.

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

Fig. 1
Figs. 2–10
Figs. 11–19
Figs. 20–23
Figs. 24–27
Figs. 28–30

Similar content being viewed by others

References

  • Abdel-Rahman AM (1996) Pan-African volcanism: petrology and geochemistry of the Dokhan Volcanic suite in the northern Nubian Shield. Geol Mag 133:17–31

    Article  Google Scholar 

  • Ahmed AF (2003) Petrology of the Late-Precambrian Dokhan volcanics in Gabal Magal El Rashaydah-Fatera El-Zarga belt, north Eastern Desert, Egypt. 3d International conference on the geology of Africa, pp 255–280

  • Akaad MK, Noweir AM (1980) Geology and lithostratigraphy of the Arabian Desert orogenic belt of Egypt between latitudes 25°35'S and 26°30'N. Inst Appl Geol Jeddah Bull 3:127–135

  • Ayers JC, Watson EB (1993) Rutile solubility and mobility in supercritical aqueous fluids. Contrib Mineral Petrol 114:321–330

    Article  Google Scholar 

  • Bailey RC, Head G, Jenike M, Owen B, Rechtman R, Zechenter E (1989) Hunting and gathering in tropical rain forest: is it possible? Am Anthropol 91:59–82

    Article  Google Scholar 

  • Basta EZ, Kotb H, Awadalla MF (1980) Petrochemical and geochemical characteristics of the Dokhan formation at the type locality, Jabal Dokhan, Eastern Desert, Egypt. Inst Appl Geol Jeddah Bull 3:121–140

    Google Scholar 

  • Best MG, Christiansen EH (2001) Igneous petrology. Blackwell Science, Oxford, p 458

    Google Scholar 

  • Blasy M (2000) Petrogenesis of Safaga Dokhan volcanics, Eastern Desert, Egypt. Egypt J Geol 44 ∕ 2:101–113

    Google Scholar 

  • Clarke LB, Le Bas MJ (1990) Magma mixing and metasomatic reaction in silicate–carbonate liquids at the Kruidfontein carbonatitic volcanic complex. Transvall Mineral Mag 54:65–109

    Google Scholar 

  • Condie KC, Potts MJ (1964) Calcalkline volcanism and thickness of the Early Precambrian crust in North America. Can J Earth Sci 6:1179–1184

    Article  Google Scholar 

  • Donaldson CM, Henderson CMB (1988) A new interpretation of round embayments in quartz crystals. Min Mag 52:27–33

    Article  Google Scholar 

  • El Gaby S (1975) Petrochemistry and geochemistry of some granites from Egypt. N Jb Mineral (Abh) 124:89–148

    Google Scholar 

  • El Gaby S (1994) Geology and tectonic framework of the Pan-African Orogenic Belt in Egypt. 2nd Int. Conf. Geol. Arab word. Cairo, Abstract, pp 66–68

  • El Gaby S, List FK, Tehrani R (1988) Geology, evolution and metallogenesis of the Pan-African belt in Egypt. In: El Gaby S, Greiling RO (eds) The Pan-African belt of Northeast Africa and adjacent areas. Braun, Schweig, Vieweg, Wiesbaden, pp 17–68

    Google Scholar 

  • El Ramly MF (1972) A new geological map for the basement rocks in the eastern and southwestern deserts of Egypt. Ann Geol Surv Egypt 2:1–18

    Google Scholar 

  • El Sayed MM, Obeid MA, Furnes H, Moghazi AM (2004) Late Neoproterozoic volcanism in the southern Eastern Desert, Egypt: petrological, structural, and geochemical constraints on the tectonic–magmatic evolution of the Allaqi Dokhan volcanic suite. N Jb Mineral (Abh) 180(3):261–286

    Article  Google Scholar 

  • El Shazly EM (1977) The geology of the Egyptian region. In: Narin AE, Kanes WH, Stehli FG (eds) The ocean basins and margins, 4A, the eastern Mediterranean. Plenum Press, New York, pp 379–444

    Chapter  Google Scholar 

  • Eliwa HA, Kimura JI, Itaya T (2006) Late Neoproterozoic Dokhan volcanics, North Eastern Desert, Egypt: geochemistry and petrogenesis. Precambrian Res 151:31–52

    Article  Google Scholar 

  • El-khadragy AA, Azab AA (2013) Contribution the crustal structure of Egypt, using the Bouguer gravity data. Pure Appl Geophys :2207–2229

  • Fritz H, Wallbrecher E, Khudeir AA, Abu El Ela FF, Allmeyer DR (1996) Formation of Neoproterozoic metamorphic core complexes during oblique convergence, Eastern Desert, Egypt. J Afr Earth Sci 23:311–329

    Article  Google Scholar 

  • Green TH, Sie SH, Ryan CG, Cousens DR (1989) Proton microprobe determined partitioning of Nb, Ta, Zr, Sr and Y between garnet, clinopyroxene and basaltic magma at high pressure and temperature. Chem Geol 74:201–216

    Article  Google Scholar 

  • Grothaus B, Eppler D, Ehrlich R (1979) Depositional environments and structural implications of the Hammamat Formation, Egypt. Ann Geol Surv Egypt 9:564–590

    Google Scholar 

  • Grove TL, Gerlach DC, Sando TW (1982) Origin of calc-alkaline series lavas at Medicine Lake volcano by fractionation, assimilation and mixing. Contr Min Petrol 80:160–182

  • Haggerty SE (1978) The redox state of planetary basalts. Geophys Res Lett 5:443–446

    Article  Google Scholar 

  • Hassan MA, Hashad AH (1990) Precambrian of Egypt. In: Said R (ed) The geology of Egypt. Alkema, Rotterdam, pp 201–245

    Google Scholar 

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

    Article  Google Scholar 

  • Hilmy ME, Meeneisy MY, Ragab AL, Hammad HM (1980) Petrology of the volcanic rocks of Gabal Nuqara, West of Safaga. Ain Shams Sci Bull V 22(B)

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

    Article  Google Scholar 

  • Jarrar G, Stern RJ, Saffarini G, Al-Zubi H (2003) Late- and post-orogenic Neoproterozoic intrusions of Jordan: implications for crustal growth in the northernmost segment of the East African Orogen. Precambrian Res 123:295–319

    Article  Google Scholar 

  • Kinzler BJ, Grove TL, Recca SI (1990) An experimental study on the effect of temperature and melt composition on partitioning of nickel between olivine and silicate melt. Geochim Cosmochim Acta 54:1255–1265

    Article  Google Scholar 

  • Kuno H (1968) Differentiation of basalt magmas. In: Hess HH, Poldevaart A (eds) Basalts—the Poldevaart treatise on rocks of basaltic composition. Interscience, New York, pp 623–688

    Google Scholar 

  • Le Maitre RW (1989) Classification of igneous rocks and glossary of terms. Blackwell, Sci. Pub, London, 193p

    Google Scholar 

  • Meen JK (1990) Elevation of potassium content of basaltic magma by fractional crystallization: the effect of pressure. Contrib Mineral 104:309–331

  • Moghazi AM (2003) Geochemistry and petrogenesis of a high-K calc-alkaline Dokhan Volcanic suite, South Safaga area, Egypt: the role of late Neoproterozoic crustal extension. Precambrian Res 125:161–178

    Article  Google Scholar 

  • Mohammed FH, Moghazi AM, Hassanen MA (2000) Geochemistry, petrogenesis and tectonic setting of Late Neoproterozoic Dokhan-type volcanic rocks in Fatira area, eastern Egypt. Int J Earth Sci 88:764–777

    Article  Google Scholar 

  • Nelson SA (1981) The possible role of thermal feedback in the eruption of siliceous magmas. J Volcanol Geotherm Res 11:127–137

    Article  Google Scholar 

  • Pearce JA (1983) Role of the Sub-continental lithosphere in magma genesis at active continental margins. In: Hawkes-worth CJ, Norry MJ (eds) Continental basalt and mantle xenoliths. Shiva Publishing Limited, pp 230–249

  • Pearce JA, Cann JR (1973) Tectonic setting of basic volcanic rocks determined using trace elements analysis. Earth Planet Sci Lett 19:290–300

    Article  Google Scholar 

  • Pearce JA, Harris NBW, Tindle AG (1984) Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. J Petrol 25:956–983

    Article  Google Scholar 

  • Peccerillo A, Taylor SR (1976) Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, northern Turkey. Contrib Mineral Petrol 58:63–81

    Article  Google Scholar 

  • Powell M (1978) Crystallization conditions of low-pressure cumulate nodules from the Lesser Antilles island arc. Earth Planet Sci Lett 34:162–172

    Article  Google Scholar 

  • Ramsay CR, Basahel AN, Jackson NJ (1981) Petrography, geochemistry and origin of the volcano-sedimentary succession between Jabel Ibrahim and Alqiq, Saudi Arabia. Bull Fac Earth Sci King Abdulaziz Univ 4:1–24

    Google Scholar 

  • Ressetar R, Monard JR (1983) Chemical composition and tectonic setting of the Dokhan Volcanic formation, Eastern Desert, Egypt. J Afr Earth Sci 1:103–112

    Google Scholar 

  • Ries AC, Shackelton RM, Graham RH, Fitches WR (1983) Pan-African structures, ophiolites and mélange in the Eastern Desert of Egypt: a traverse at 26 N. J Geol Soc Lond 140:75–95

    Article  Google Scholar 

  • Sakuyama M (1983) Petrology of arc volcanic rocks and their origin by mantle diapirs. J Volcanol Geotherm Res 18:297–320

    Article  Google Scholar 

  • Shapiro L, Bannock WW (1962) Rapid analysis of silicate carbonate and phosphate rocks. USGS Buii 1144 A

  • Stern RJ (1981) Petrgenessis and tectonic setting of Late Precambrian ensimatic rocks, central Eastern Desert of Egypt. Precambrian Res 16:195–230

    Article  Google Scholar 

  • Stern RJ (1994) Arc assembly and continental collision in the Neoproterozoic East African Orogin: implications for the consolidation of Gondwanaland. Ann Rev Earth Planet Sci 22:319–351

    Article  Google Scholar 

  • Stern RJ, Gottfried D (1986) Petrogenesis of Late Precambrian (575–600 Ma) bimodal suite in northeast Africa. Contrib Mineral Petrol 92:492–501

    Article  Google Scholar 

  • Stern RJ, Hedge CE (1985) Geochronologic and isotopic constraints on late Precambrian crustal evolution in the Eastern Desert of Egypt. Am J Sci 285:97–127

    Article  Google Scholar 

  • Stern RJ, Gottfried D, Hedge CE (1984) Late Precambrian rifting and crustal evolution in the northeast Desert of Egypt. Geology 12:168–172

    Article  Google Scholar 

  • Stern RJ, Sellers G, Gottfried D (1988) Bimodal dyke swarms in the North Eastern Desert of Egypt: significance for the origin of late Precambrian “A-type” granites in northern Arabia. In: El Gaby S, Greiling RO (eds) The Pan African Belt of Northeast Africa and adjacent Area. Vieweg, Weisbaden, pp 147–177

    Google Scholar 

  • Tatsumi Y, Eggins S (1995) Subduction zone magmatism. Blackwell Science, Boston

    Google Scholar 

  • Thorpe RS, Francis PW, O’Callaghan L (1984) Relative roles of source composition, fractional crystallisation and crustal contamination in the petrogenisis of Andean volcanic rocks. Phil Trans R Soc London A310:675–692

    Article  Google Scholar 

  • Willis KM, Stern RJ, Clauer N (1988) Age and geochemistry of late Precambrian sediments of the Hammamat Series from the northeastern Desert of Egypt. Precambrian Res 42:173–187

    Article  Google Scholar 

  • Wilson M (1993) Igneous petrogenesis. Chapman and Hall, London, p 466

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Geology Department, Faculty of Science, Zagazig University, Zagazig, Egypt

    Sayed A. Azzaz, M. Blasy & O. Amer

  2. Nuclear Materials Authority of Egypt, Cairo, Egypt

    A. Moharem

Authors
  1. Sayed A. Azzaz
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. M. Blasy
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. A. Moharem
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. O. Amer
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Sayed A. Azzaz.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Azzaz, S.A., Blasy, M., Moharem, A. et al. Late Neoproterozoic Dokhan volcanics, around G. Esh, North Eastern Desert, Egypt: geochemistry and relation of K2O and Nb abundances with crustal thickness. Arab J Geosci 8, 3551–3564 (2015). https://doi.org/10.1007/s12517-014-1451-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12517-014-1451-6

Keywords

Search

Navigation