Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-26T18:41:59.951Z Has data issue: false hasContentIssue false

Geochemistry, age and origin of the Mons Claudianus TTG batholith (Egypt): insight into the role of Pan-African magmatism in uniting plates of Gondwana

Published online by Cambridge University Press:  07 June 2018

ABDEL-FATTAH M. ABDEL-RAHMAN*
Affiliation:
Department of Geology, American University of Beirut, P.O. Box 11–0236, Bliss Street, Beirut, Lebanon
*
Author for correspondence: [email protected]

Abstract

The tonalite–trondhjemite–granodiorite (TTG) Mons Claudianus Batholith (MCB) of Egypt is subsolvus, metaluminous to mildly peraluminous, exhibits wide ranges of SiO2, Al2O3, Sr, Rb, Zr, shows large Ba enrichment, is moderately enriched in rare earth elements (REE) and is depleted in K, Ti, Nb, Y, Hf and heavy REE (HREE), reflecting strong arc geochemical signatures. Moderate fractionation of REE and lack of Eu anomaly characterize the MCB. It is typical of high-Al TTGs of volcanic-arc affinities. U–Pb–zircon dating produced a Pan-African age of 664.12 ± 0.38 Ma. The MCB exhibits 87Sr/86Sr isotopic compositions of 0.70352–0.70626 (initial Sr ratio of 0.70259) and 143Nd/144Nd ratios of 0.51261–0.51276 (εNd; –0.5 to +2.4), suggestive of a mantle source. Anatexis of a basaltic slab under eclogitic conditions leaving garnet in the residue produces high-Al TTG rocks characterized by low Yb values (<1.8 ppm). Values (in ppm) of Yb (0.65–1.8), Y (2.2–19), Nb (1.2–6.4), and ratios of Nb/Ta (7–17), (La/Yb)N of 11.7, Sr/Y and Zr/Sm (58 and 45, respectively) are all consistent with anatexis of a basaltic slab under eclogitic conditions, leaving garnet in the residue to produce this high-Al TTG suite. The data conform to magma generation via partial melting (F = 0.25–0.50) leaving 15–25 % garnet in the residue. Voluminous synorogenic magmatic pulses, resulting from slab melting during the closure of the Mozambique Ocean via convergence of east and west Gondwana, produced the MCB and similar large batholiths forming the core of Pan-African belts. These belts welded together vestiges of fragmented Rodinia, assembling them into a united Gondwana.

Type
Original Article
Copyright
Copyright © Cambridge University Press 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abdel-Rahman, A. M. 1990. Petrogenesis of early-orogenic diorites, tonalities and post-orogenic trondhjemites in the Nubian Shield. Journal of Petrology 31, 1285–312.CrossRefGoogle Scholar
Abdel-Rahman, A. M. 1995. Tectonic-magmatic stages of shield evolution: the Pan-African belt in northeastern Egypt. Tectonophysics 242, 223–40.CrossRefGoogle Scholar
Abdel-Rahman, A. M. 1996. Pan African volcanism: petrology and geochemistry of the Dokhan Volcanic Suite in the northern Nubian shield. Geological Magazine 133, 1731.CrossRefGoogle Scholar
Abdel-Rahman, A. M. 2006. Petrogenesis of anorogenic peralkaline granitic complexes from eastern Egypt. Mineralogical Magazine 70, 2750.CrossRefGoogle Scholar
Abdel-Rahman, A. M. 2010. Nature of feldspars in felsic plutonic complexes from northeastern Egypt: implications for the evolution of orogenic and anorogenic magmas. Neues Jahrbuch für Geologie und Paläontologie Abhandlungen 257, 147–68.CrossRefGoogle Scholar
Abdel-Rahman, A. M. 2016. Mineralogy of the Neoproterozoic epidote-bearing TTG suite, Mons Claudianus batholith (Egypt) and implications for synorogenic magmatism. Mineralogical Magazine 80, 1291–314.CrossRefGoogle Scholar
Abdel-Rahman, A. M. & 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 138, 6785.CrossRefGoogle Scholar
Abdel-Rahman, A. M. & Martin, R. F. 1987. Late Pan-African magmatism and crustal development in northeastern Egypt. Geological Journal 22, 281301.CrossRefGoogle Scholar
Abdel-Rahman, A. M. & Martin, R. F. 1990. The Mount Gharib A-type granite, Nubian shield: petrogenesis and role of metasomatism at the source. Contributions to Mineralogy and Petrology 104, 173–83.CrossRefGoogle Scholar
Abdel-Rahman, Y., Ploat, A., Dilek, Y., Fryer, B., El-Sharkawy, M. & Sakran, S. 2009. Geochemistry and tectonic evolution of the Neoproterozoic WadiGhadir ophiolite, Eastern Desert, Egypt. Lithos 113, 158–78.CrossRefGoogle Scholar
Affaton, P. 1998. Geology of Western Gondwana (2000–500 Ma): Pan-African – Brasiliano Aggregation of South America and Africa. American Journal of Science 298, 611–15.Google Scholar
Ali, K. A., Azer, M. K., Gahlan, H. A., Wilde, S. A., Samuel, M. D. & Stern, R. J. 2010. Age constraints on the formation and emplacement of Neoproterozoic ophiolites along the Allaqi–Heiani Suture, South Eastern Desert of Egypt. Gondwana Research 18, 583–95.CrossRefGoogle Scholar
Almeida, J. A. C., Dall'Agnol, R., Oliveira, M. A., Macambirab, M. J. B., Pimenteld, M. M., Rämöe, O. T., Guimarãesa, F. V. & Leite, A. A. S. 2011. Zircon geochronology, geochemistry and origin of the TTG suites of the Rio Maria granite-greenstone terrane: implications for the growth of the Archean crust of the Carajás province, Brazil. Precambrian Research 187, 201–21.CrossRefGoogle Scholar
Almeida, J. A. C., Dall'Agnol, R. & Rocha, M. C. 2017. Tonalite–trondhjemite and leucogranodiorite–granite suites from the Rio Maria domain, Carajas Province, Brazil: implications for discrimination and origin of the Archean Na-granitoids. Canadian Mineralogist 55, 437–56.CrossRefGoogle Scholar
Ashwal, L. D., Demaiffe, D. & Torsvik, T. H. 2002. Petrogenesis of Neoproterozoic granitoids and related rocks from the Seychelles: evidence for the case of an Andean-type arc origin. Journal of Petrology 43, 4583.CrossRefGoogle Scholar
Atherton, M. P., McCourt, W. J., Sanderson, L. M. & Taylor, W. P. 1979. The geochemical character of the segmented Peruvian Coastal batholith and associated volcanics. In Origin of Granite Batholiths: Geochemical Evidence (eds Atherton, M. P. & Tarney, J.), pp. 4564. Nantwich: Shiva.CrossRefGoogle Scholar
Barker, F. 1979. Trondhjemite: definition, environment and hypothesis of origin. In Trondhjemites, Dacites and Related Rocks (ed. Barker, F.), pp. 112. Amsterdam: Elsevier.Google Scholar
Barker, F. & Arth, J. G. 1976. Generation of trondhjemitic-tonalitic liquids and Archean bimodal trondhjemite basalt suites. Geology 4, 596600.2.0.CO;2>CrossRefGoogle Scholar
Barker, F., Peterman, Z. E. & Friedman, L. 1976. The 1.7 to 1.8 b.y. old trondhjemites of southwestern Colorado and northern New Mexico: geochemistry and depths of genesis. Geological Society of America Bulletin 87, 189–98.2.0.CO;2>CrossRefGoogle Scholar
Barr, S. M., White, C. E. & Culshaw, N. G. 2001. Geology and tectonic setting of Paleoproterozoic granitoid suite in the Island Harbour Bay area, Makkovick Province, Labrador. Canadian Journal of Earth Sciences 38, 441–63.CrossRefGoogle Scholar
Bédard, J. H. 2003. Evidence for regional-scale, pluton-driven, high-grade metamorphism in the Archean Minto Block, northern Superior Province, Canada. Journal of Geology 111, 183205.CrossRefGoogle Scholar
Berhe, S. M. 1990. Ophiolites in Northeast and East Africa: implications for Proterozoic crustal growth. Journal of the Geological Society, London 147, 4157.CrossRefGoogle Scholar
Blasband, B., White, S., Broijmans, P., De Boorder, H. & Visser, W. 2000. Late Proterozoic extensional collapse in the Arabian-Nubian shield. Journal of the Geological Society of London 157, 615–28.CrossRefGoogle Scholar
Blundy, J. D. & Holland, T. J. B. 1990. Calcic amphibole equilibria and a new amphibole-plagioclase geothermometer. Contributions to Mineralogy and Petrology 104, 208–24.CrossRefGoogle Scholar
Cahen, L., Snelling, N. J., Delhal, J. & Vail, J. R. 1984. The Geochronology and Evolution of Africa. Oxford: Clarendon, 371 pp.Google Scholar
Coleman, R. G. & Peterman, Z. E. 1975. Oceanic plagiogranite. Journal of Geophysical Research 80, 1099–108.CrossRefGoogle Scholar
Collins, A. S. & Pisarevsky, S. A. 2005. Amalgamating eastern Gondwana: the evolution of the circum-Indian orogens. Earth-Science Reviews 71, 229–70.CrossRefGoogle Scholar
Condie, K. C. 2005. TTGs and adakites: are they both slab melts?. Lithos, 80, 3344.CrossRefGoogle Scholar
Dahlquist, J. A. 2001. REE fractionation by accessory minerals in epidote-bearing metaluminous granitoids from the Sierras Pampeanas, Argentina. Mineralogical Magazine 65, 463–75.CrossRefGoogle Scholar
Dalziel, I. W. D. 1991. Pacific margins of Laurentia and East Antarctica – Australia as a conjugate rift pair: evidence and implications for an Eocambrian supercontinent. Geology 19, 598601.2.3.CO;2>CrossRefGoogle Scholar
Dalziel, I. W. D. 1992. On the organisation of American plates in the Neoproterozoic and the breakout of Laurentia. GSA Today 2, 237–41.Google Scholar
Dalziel, I. W. D. 1997. Overview: Neoproterozoic-Paleozoic geography and tectonics: review, hypothesis, environmental speculation. Geological Society of America Bulletin 109, 1642.2.3.CO;2>CrossRefGoogle Scholar
Davidson, J. P. 1987. Crustal contamination versus subduction zone enrichment: examples from the Lesser Antilles and implications for the mantle source composition of island arc volcanic rocks. Geochimica et Cosmochimica Acta 51, 2185–98.CrossRefGoogle Scholar
Defant, M. J. & Drummond, M. S. 1990. Derivation of some modern arc magmas by melting of young subducted. lithosphere. Nature 367, 662–5.CrossRefGoogle Scholar
de Wall, H., Pandit, M. K., Dotzler, R. & Just, J. 2012. Cryogenian transpression and granite intrusion along the western margin of Rodinia (Mt. Abu region): magnetic fabric and geochemical inferences on Neoproterozoic geodynamics of the NW Indian block. Tectonophysics 554–557, 143–58.CrossRefGoogle Scholar
Dissanayake, C. B. & Chandrajith, R. 1999. Sri Lanka – Madagascar Gandwana linkage: evidence for a Pan-African mineral belt. Journal of Geology 107, 223–35.CrossRefGoogle Scholar
Drummond, M. S. & Defant, M. J. 1990. A model for trondhjemite–tonalite–dacite genesis and crustal growth via slab melting: Archaean to modern comparisons. Journal of Geophysical Research 95, 21503–21.CrossRefGoogle Scholar
El-Bialy, M. Z. 2013. Geochemistry of the Neoproterozoic metasediments formation, Kid metamorphic complex, Sinai, Egypt: implications for source-area weathering, provenance, recycling and depositional tectonic setting. Lithos 175, 6885.CrossRefGoogle Scholar
Eliwa, H. A., Kimura, J. I. & Itaya, T. 2006. Late Neoproterozoic Dokhan Volcanics, North Eastern Desert, Egypt: geochemistry and petrogenesis. Precambrian Research 151, 3152.CrossRefGoogle Scholar
El-Ramly, M. F. 1972. A new geological map for the basement rocks in the Eastern and South-Western Desert of Egypt. Annals of the Geological Survey of Egypt 2, 118.Google Scholar
El-Ramly, M. F. & Hussein, A. A. 1985. The ring complexes of the Eastern Desert of Egypt. Journal of African Earth Sciences 3, 7782.CrossRefGoogle Scholar
El-Shazly, S. M. & El-Sayed, M. M. 2000. Petrogenesis of the Pan-African El-Bula igneous suite, central Eastern Desert, Egypt. Journal of African Earth Sciences 31, 317–36.CrossRefGoogle Scholar
Evans, B. W. & Vance, J. A. 1987. Epidote phenocrysts in dacitic dikes, Boulder County, Colorado. Contributions to Mineralogy and Petrology 96, 178–85.CrossRefGoogle Scholar
Farrow, C. E. G. & Barr, S. M. 1992. Petrology of high-Al-hornblende and magmatic epidote-bearing plutons in the southeastern Cape Breton Highlands, Nova Scotia. Canadian Mineralogist 30, 377–92.Google Scholar
Faure, G. 1986. Principles of Isotope Geology, 2nd edn. New York: John Wiley & Sons, 589 pp.Google Scholar
Foley, S. F., Tiepolo, M. & Vannucci, R. 2002. Growth of early continental crust controlled by melting of amphibolite in subduction zones. Nature 417, 837–40.CrossRefGoogle ScholarPubMed
Franz, G. & Smelik, E. A. 1995. Zoned zoisite from Weissenstein pegmatite that derived from high-pressure melting of eclogite at ≈ 2.0 GPa: importance for decompressional melting in Eclogite. European Journal of Mineralogy 7, 1421–36.CrossRefGoogle Scholar
Frisch, W. & Abdel-Rahman, A. M. 1999. Petrogenesis of the Wadi Dib alkaline ring complex, Eastern Desert of Egypt. Mineralogy and Petrology 65, 249–75.CrossRefGoogle Scholar
Green, T. H. & Ringwood, A. E. 1968. Genesis of the calc-alkaline igneous rock suite. Contributions to Mineralogy and Petrology 18, 105–62.CrossRefGoogle Scholar
Halla, J., van Hunen, J., Heilimo, E. & Hölttä, P. 2009. Geochemical and numerical constraints on Neoarchean plate tectonics. Precambrian Research 179, 155–62.CrossRefGoogle Scholar
Hammarstrom, J. M. & Zen, E.-A. 1986. Aluminum in hornblende: an empirical igneous geobarometer. American Mineralogist 71, 1297–313.Google Scholar
Handke, M. J., Tucker, R. D., & Ashwal, L. D. 1999. Neoproterozoic continental arc magmatism in west-central Madagascar. Geology 27, 351–4.2.3.CO;2>CrossRefGoogle Scholar
Hanson, R. E., Wilson, T. J. & Munyanyiwa, H. 1994. Geologic evolution of the Neoproterozoic Zambezi orogenic belt in Zambia. Journal of African Earth Sciences 18, 135–50.CrossRefGoogle Scholar
Hargrove, U., Martin, M. W., Hanson, R. E., Singletary, S., Bowring, S. & Munyanyiwa, H. 1998. Tectonic inversion of the Paleo- and Neoproterozoic metamorphic rocks in the Zambezi belt, Mt. Darwin area, NE Zimbabwe. Geological Society of America Abstracts with Programs 30, A–292.Google Scholar
Harris, N. B. W. 1985. Alkaline complexes from the Arabian Shield. Journal of African Earth Science 3, 83–8.CrossRefGoogle Scholar
Haydoutov, I. & S. Yanev, S. 1997. The protomoesian microcontinent of the Balkans Peninsula – a peri Gondvanian piece. Tectonophysics 272, 303–13.CrossRefGoogle Scholar
Hoffman, P. F. 1991. Did the breakout of Laurentia turn Gondwanaland inside-out? Science 252, 1409–12.CrossRefGoogle ScholarPubMed
Hoffman, P. F. 1999. The break-up of Rodinia, birth of Gondwana, true polar wander and the snowball Earth. Journal of African Earth Sciences 28, 1733.CrossRefGoogle Scholar
Hollister, L. S., Grissom, G. C., Peters, E. K., Stowell, H. H. & Sisson, V. B. 1987. Confirmation of the empirical correlation of Al in hornblende with pressure of solidification of calc-alkaline plutons. American Mineralogist 72, 231–9.Google Scholar
Hume, W. R. 1934. The Geology of Egypt, vol. 2: The Fundamental Pre-Cambrian Rocks of Egypt and the Sudan, their distribution, Age and Character. Part 1: The Metamorphic Rocks. Cairo: Government Press, 134 pp.Google Scholar
Jacobs, J., Fanning, C. M., Henjes-Kunst, F., Olesch, M. & Paech, H. J. 1998. Continuation of the Mozambique belt into East Antarctica: Grenville-age metamorphism and polyphase Pan-African high-grade events in Central Dronning Maud Land. Journal of Geology 106, 385406.CrossRefGoogle Scholar
Johnson, P. R. & Woldehaimanot, B. 2003. Development of the Arabian-Nubian shield: perspectives on accretion and deformation in the northern East African Orogen and the assembly of Gondwana. In The Timing and Location of Major Ore Deposits in an Evolving Orogen (eds Blundell, D. J., Neubauer, F. & von Quadt, A.), pp. 289325. Geological Society of London Special Publication no. 206.Google Scholar
Keppie, J. D. & Dostal, J. 1991. Late Proterozoic tectonic model for the Avalon Terrane in Maritime Canada. Tectonics 10, 842–50.CrossRefGoogle Scholar
Krogh, T. E. 1973. A low contamination method for the hydrothermal decomposition of zircon and extraction of U and Pb for isotopic age determinations. Geochimica et Cosmochimica Acta 37, 485–94.CrossRefGoogle Scholar
Krogh, T. E., Strong, D. F., O'Brien, S. J. & Papezik, V. 1988. Precise U-Pb zircon dates from the Avalon Terrane in Newfoundland. Canadian Journal of Earth Sciences 25, 442–53.CrossRefGoogle Scholar
Kuno, H. 1968. Differentiation of basalt magmas. In 77th Poldervaart Treatise, on Rocks of Basaltic Composition, vol. 2 (eds Hess, H. H. & Poldervaart, A.), pp. 623–88. New York: Interscience.Google Scholar
Landoll, J. D., Foland, K. A. & Henderson, C. M. 1994. Nd-isotopes demonstrate the role of contamination in the formation of coexisting quartz- and nepheline syenites at the Abu Khruq complex, Egypt. Contributions to Mineralogy and Petrology 117, 305–29.CrossRefGoogle Scholar
Laurent, O., Martin, H., Moyen, J. F. & Doucelance, R. 2014. The diversity and evolution of late-Archean granitoids: evidence for the onset of ‘modern-style’ plate tectonics between 3.0 and 2.5 Ga. Lithos 205, 208–35.CrossRefGoogle Scholar
Martin, H. 1987. Petrogenesis of Archean trondhjemites, tonalites, and granodiorites from Eastern Finland: major and trace element geochemistry. Journal of Petrology 28, 921–53.CrossRefGoogle Scholar
Martin, H. 1993. The mechanisms of petrogenesis of the Archean continental crust: comparison with modem processes. Lithos 30, 373–88.CrossRefGoogle Scholar
Martin, H. 1999. The adakitic magmas: modern analogues of Archaean granitoids. Lithos 46, 411–29.CrossRefGoogle Scholar
Martin, H. & Moyen, J. F. 2002. Secular changes in TTG composition as markers of the progressive cooling of the Earth. Geology 30, 319–22.2.0.CO;2>CrossRefGoogle Scholar
Martin, H., Smithies, R. H., Rapp, R., Moyen, J. F. & Champion, D. 2005. An overview of adakite, tonalite–trondhjemite–granodiorite (TTG) and sanukitoid: relationships and some implications for crustal evolution. Lithos 79, 124.CrossRefGoogle Scholar
Maurice, A. E., Basta, F. F. & Khiamy, A. A. 2012. Neoproterozoic nascent island arc volcanism from the Nubian shield of Egypt: magma genesis and generation of continental crust in intra-oceanic arcs. Lithos 132, 120.CrossRefGoogle Scholar
Meert, J. G. 2002. A synopsis of events related to the assembly of eastern Gondwana. Tectonophysics 374, 140.Google Scholar
Meert, J. G. & Lieberman, B. S. 2008. The Neoproterozoic assembly of Gondwana and its relationship to the Ediacaran–Cambrian radiation. Gondwana Research 14, 521.CrossRefGoogle Scholar
Meert, J. G. & Torsvik, T. H. 2003. The making and unmaking of a supercontinent: Rodinia revisited. Tectonophysics 375, 261–88.CrossRefGoogle Scholar
Meert, J. G. & Van der Voo, R. 1996. Paleomagnetic and 40Ar/39Ar study of the Sinyai dolerite, Kenya: implications for Gondwana assembly. Journal of Geology 104, 131–42.CrossRefGoogle Scholar
Meert, J. G. & Van der Voo, R. 1997. The assembly of Gondwana 800–550 Ma. Journal of Geodynamics 23, 223–35.CrossRefGoogle Scholar
Middlemost, E. A. K. 1997. Magmas, Rocks and Planetary Development. Harlow: Longman, 299 pp.Google Scholar
Moyen, J. F. 2009. High Sr/Y and La/Y ratios: the meaning of the ‘adakitic signature’. Lithos 112, 556–74.CrossRefGoogle Scholar
Moyen, J. F., Jayananda, H. & Auvray, M. B. 2003. Late Archaean granites: a typology based on the Dharwar Craton (India). Precambrian Research 127, 103–23.CrossRefGoogle Scholar
Moyen, J. F. & Stevens, G. 2006. Experimental constraints on TTG petrogenesis: implications for Archean geodynamics. In Archean Geodynamics and Environments (eds Benn, K., Mareschal, J.-C. & Condie, K. C.), pp. 149–78. AGU Geophysical Monograph 164.CrossRefGoogle Scholar
Moyen, J. F., Stevens, G., Kisters, A. F. M. & Belcher, R. W. 2007. TTG plutons of the Barberton granitoid-greenstone terrain, South Africa. In Earth's Oldest Rocks (eds Van Kranendonk, M. J., Smithies, R. H. & Bennet, V.), 606–68. Developments in Precambrian Geology 15Google Scholar
Nohada, S. & Wasserburg, G. J. 1981. Nd and Sr isotopic study of volcanic rocks from Japan. Earth and Planetary Science Letters 52, 264–76.CrossRefGoogle Scholar
O'Connor, J. T. 1965. A classification for quartz-rich igneous rocks based on feldspar ratios. US Geological Survey Professional Paper 525-B, 7984.Google Scholar
Pearce, J. A., Harris, N. B. W. & Tindle, A. G. 1984. Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. Journal of Petrology 25, 956–83.CrossRefGoogle Scholar
Popov, V. S., Nikiforova, N. F. & Bogatov, V. I. 2001. Multiple gabbro-granite intrusive series of the Syrostan pluton, southern Urals: geochemistry and petrology. Geochemistry International 39, 732–47.Google Scholar
Prouteau, G., Scaillet, B., Pichavant, M. & Maury, R. C. 2001. Evidence for mantle metasomatism by hydrous silicic melts derived from subducted oceanic crust. Nature 410, 197200.CrossRefGoogle ScholarPubMed
Rapp, R. P., Shimizu, N. & Norman, M. D. 2003. Growth of early continental crust by partial melting of eclogite. Nature 425, 605–9.CrossRefGoogle ScholarPubMed
Rapp, R. P., Shimizu, N., Norman, M. D. & Applegate, G. S. 1999. Reaction between slab-derived melts and peridotite in the mantle wedge: experimental constraints at 3.8 GPa. Chemical Geology 160, 335–56.CrossRefGoogle Scholar
Santos, L. C. M. L., Dantas, E. L., Cawood, P. A., Santos, E. J. & Fuck, R. A. 2017. Neoarchean crustal growth and Paleoproterozoic reworking in the Borborema Province, NE Brazil: insights from geochemical and isotopic data of TTG and metagranitic rocks of the Alto Moxoto Terrane. Journal of South American Earth Sciences 79, 342–63.CrossRefGoogle Scholar
Savov, I., Ryan, J., Haydoutov, I. & Schijf, J. 2001. Lare Precambrian Balkan-Carpathian ophiolite – a slice of the Pan-African ocean crust?: geochemical and tectonic insights from the Tcherni Vrah and Deli Jovan massifs, Bulgaria and Serbia. Journal of Volcanology and Geothermal Research 110, 299318.CrossRefGoogle Scholar
Schmidt, M. W., Dardon, A., Chazot, G. & Vannucci, R. 2004. The dependence of Nb and Ta rutile-melt partitioning on melt composition and Nb/Ta fractionation during subduction processes. Earth and Planetary Science Letters 226, 415–32.CrossRefGoogle Scholar
Schmidt, M. W. & Poli, S. 2004. Magmatic epidote. Reviews in Mineralogy & Geochemistry 56, 399430.CrossRefGoogle Scholar
Schmitt, A. K., Emmermann, R., Trumbull, R. B., Buèhn, B. & Henjes-Kunst, F. 2000. Petrogenesis and 40Ar/39Ar geochronology of the Brandberg complex, Namibia: evidence for a major mantle contribution in metaluminous and peralkaline granites. Journal of Petrology 41, 1207–39.CrossRefGoogle Scholar
Schuermann, H. M. 1966. The Pre-Cambrian along the Gulf of the Suez and the Northern Part of the Red Sea. Leiden: E.J. Brill, 76 pp.Google Scholar
Shackleton, R. M. 1996. The final collision zone between East and West Gondwana: where is it? Journal of African Earth Sciences 23, 271–87.CrossRefGoogle Scholar
Silva, L. C., McNaughton, N. J., Armstrong, R., Hartmann, L. A. & Fletcher, I. R. 2005a. The Neoproterozoic Mantiqueira Province and its African connections: a zircon-based U–Pb geochronologic subdivision for the Brasiliano/Pan-African systems of orogens. Precambrian Research 136, 203–40.CrossRefGoogle Scholar
Silva, L. C., McNaughton, N. J. & Fletcher, I. R. 2005 b. SHRIMP U–Pb zircon geochronology of Neoproterozoic crustal granitoids (Southern Brazil): a case for discrimination of emplacement and inherited ages. Lithos 82, 503–25.CrossRefGoogle Scholar
Smithies, R. H. & Champion, D. C. 2000. The Archaean high-Mg diorite suite: links to tonalite–trondhjemite–granodiorite magmatism and implications for early Archaean crustal growth. Journal of Petrology 41, 1653–71.CrossRefGoogle Scholar
Souza, Z. S., Potrel, H., Lafon, J. M., Althoff, F. J., Pimentel, M. M., Dall'Agnol, R. & Oliveira, C. G. 2001. Nd, Pb and Sr isotopes of the Identidade Belt, an Archaean greenstone belt of the Rio Maria region (Carajas Province, Brazil): implications for the Archaean geodynamic evolution of the Amazonian Craton. Precambrian Research 109, 293315.CrossRefGoogle Scholar
Steiger, R. H. & Jäger, E. 1977. Sub-commission on Geochronology: convention on the use of decay constants in geo- and cosmochronology. Earth and Planetary Science Letters 36, 359–62.CrossRefGoogle Scholar
Sun, S. S. & McDonough, W. F. 1989. Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. In Magmatism in Ocean Basins (eds Saunders, A. S. & Norry, M. J.), pp. 313–45. Geological Society of London, Special Publication no. 42.Google Scholar
Tohver, E., D'Agrella, M. S. & Trindade, R. J. F. 2006. Paleomagnetic record of Africa and South America for the 1200–500 Ma interval, and evaluation of Radinia and Gondwana assemblies. Precambrian Research 147, 193222.CrossRefGoogle Scholar
Trompette, R. 1994. Geology of Western Gondawana (200-500 Ma): Pan-African - Brasiliano Aggregation of South America and Africa (trans. Corozzi, A.V.). Rotterdam: Balkema, 350 pp.Google Scholar
Tucker, R. D., Ashwal, L. D., Handke, M. J., Hamilton, M. A., Le Grange, M. & Rambeloson, R. A. 1999. U-Pb geochronology and isotope geochemistry of the Archean and Proterozoic rocks of North-Central Madagascar. Journal of Geology 107, 135–53.CrossRefGoogle Scholar
Vail, J. R. 1985. Alkaline ring complexes in Sudan. Journal of African Earth Sciences 3, 51–9.CrossRefGoogle Scholar
Veevers, J. J. 2003. Pan-African is Pan-Gondwanaland: oblique convergence drives rotation during 650–500 Ma assembly. Geology 31, 501–4.2.0.CO;2>CrossRefGoogle Scholar
Veevers, J. J. 2004. Gondwanaland from 650–500 Ma assembly through 320 Ma merger in Pangea to 185–100 Ma breakup: supercontinental tectonics via stratigraphy and radiometric dating. Earth-Science Reviews 68, 1132.CrossRefGoogle Scholar
Wilson, T., Grunow, A. M. & Hanson, R. E. 1997. Gondwana Assembly: the view from southern Africa and East Gondwana. Journal of Geodynamics 23, 263–86.CrossRefGoogle Scholar
Winther, K. T. 1996. An experimentally based model for the origin of tonalitic and trondhjemitic melts. Chemical Geology 127, 4359.CrossRefGoogle Scholar
Wolf, M. B. & Wyllie, P. J. 1989. The formation of tonalitic liquids during the vapor-absent partial melting of amphibolite at 10 kb. Eos, Transactions of the American Geophysical Union 70, 506.Google Scholar
Wylie, P. J., Wolf, M. B. & van der Laan, S. R. 1997. Conditions for Formation of Tonalites and Trondhjemites: Magmatic Sources and Products. In Greenstone Belts (eds De Wit, M. & Ashwal, L. D.) pp. 256–66. Oxford: Oxford University Press.Google Scholar
Xiong, X. L., Adam, J. & Green, T. H. 2005. Rutile stability and rutile/melt HFSE partitioning during partial melting of hydrous basalt: implications for TTG genesis. Chemical Geology 218, 339–59.CrossRefGoogle Scholar
Zen, E. A. N. & Hammarstorm, J. M. 1984. Magmatic epidote and its petrologic significance. Geology 12, 515–18.2.0.CO;2>CrossRefGoogle Scholar