Abstract
This study makes a comparison of detrital-zircon age populations from upper Ediacaran greywackes of the Ossa–Morena Zone (OMZ) with those from the southern domains of the Central Iberian Zone (S-CIZ). The results reveal that the main difference between the age spectra of both populations of detrital zircon is the Neoproterozoic, in particular the Cryogenian grains. Our new data suggest that deposition in the CIZ and OMZ Ediacaran basins was coeval, indicating a long-lived magmatic event typical of the northern Gondwana margin (Avalonian–Cadomian belt and Pan-African belt). Overall, southwestern Iberia shows the following sequence of Cryogenian and Ediacaran zircon-forming events: (1) ca. 850–700 Ma, Pan-African suture (well represented in the Beiras Group and in the Mares Formation of the Série Negra succession); (2) ca. 700–635 Ma, early Cadomian arc (dominant in the Beiras Group and in the Mares Formation of the Série Negra succession); and (3) ca. 635–545 Ma, late Cadomian arc (predominant in the Mosteiros and Escoural formations of the Série Negra succession). The results emphasise that the late Ediacaran basins of southwestern Iberia evolved together in the active margin of North Gondwana in the same palaeogeographical scenario but were sufficiently separated to justify the differences identified in their Neoproterozoic detrital zircon contents. This finding shows that there is no basis for considering that the boundary between the OMZ and the S-CIZ marks a Cadomian suture.
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References
Be’eri-Shlevin, Y., Eyal, M., Eyal, Y., Whitehouse, M. J., & Litvinovsky, B. (2012). The Sa’al volcano-sedimentary complex (Sinai, Egypt): A latest Mesoproterozoic volcanic arc in the northern Arabian Nubian Shield. Geology,40, 403–406.
Gonçalves, F. (1971). Subsídios para o conhecimento geológico do Nordeste Alentejano. Memórias Serviço Geológico Portugal, nova série (Vol. 18, p. 62).
Linnemann, U., Pereira, M. F., Jeffries, T., Drost, K., & Gerdes, A. (2008). Cadomian Orogeny and the opening of the Rheic Ocean: new insights in the diacrony of geotectonic processes constrained by LA–ICP–MS U-Pb zircon dating (Ossa–Morena and Saxo-Thuringian Zones, Iberian and Bohemian Massifs). Tectonophysics,461, 21–43.
Medina, J. (1996). Contribuicão para o conhecimento da geologia do Grupo das Beiras (CXG) na região do Caramulo-Buçaco (Portugal Central) (p. 202). Unpublished PhD thesis. Portugal: Universidade de Aveiro.
Meinhold, G., Morton, A. C., Fanning, C. M., Frei, D., Howard, J. P., Phillips, R. J., et al. (2011). Evidence from detrital zircons for recycling of Mesoproterozoic and Neoproterozoic crust recorded in Paleozoic and Mesozoic sandstones of southern Libya. Earth and Planetary Science Letters,312, 164–175.
Pereira, M. F, Chichorro, M., Williams, I. S., & Silva, J. B. (2008). Zircon U–Pb geochronology of paragneisses and biotite granites from the SW Iberian Massif (Portugal): evidence for a paleogeographic link between the Ossa–Morena Ediacaran basins and the West African craton. In: J. P. Liégeois, & E. Nasser (Eds.) The Boundaries of the West African Craton: Geological Society of London Special Publication (pp. 385–408). 297.
Pereira, M. F., Chichorro, M., Solá, A. R., Silva, J. B., Sánchez-García, T., & Bellido, F. (2011). Tracing the Cadomian magmatism with detrital/inherited zircon ages by in situ U-Pb SHRIMP geochronology (Ossa–Morena Zone, SW Iberian Massif). Lithos,123, 204–217.
Pereira, M. F., Solá, A. R., Chichorro, M., Lopes, L., Gerdes, A., & Silva, J. B. (2012a). North-Gondwana assembly, break up and paleogeography: U-Pb isotope evidence from detrital and igneous zircons of Ediacaran and Cambrian rocks of SW Iberia (Estremoz Anticline). Gondwana Research,22(3–4), 866–881. doi:10.1016/j.gr.2012.02.010.
Pereira, M. F., Linnemann, U., Hofmann, M., Chichorro, M., Solá, A. R., Medina, J., et al. (2012b). The provenance of upper Ediacaran and Lower Ordovician siliciclastic rocks in the Southwest Central Iberian Zone: constraints from detrital zircon data on northern Gondwana margin evolution during the late Neoproterozoic. Precambrian Research,, 166–189, 192–195. doi:10.1016/j.precamres.2011.10.019.
Robardet, M. (2003). The Armorica ‘microplate’: fact or fiction? Critical review of the concept and contradictory palaeobiogeographical data. Palaeogeography, Palaeoclimatology, Palaeoecology,195, 125–148.
Sousa, M. B. (1984). Considerações sobre a estratigrafia do Complexo Xisto-Grauvaquico (CXG) e sua relação com o Paleozoico Inferior. Cuadernos de Geología Ibérica,9, 9–36.
Acknowledgments
This paper is a contribution to research projects GONDWANA-PTDC/CTE-GIX/110426/2009 and GOLD- PTDC/GEO–GEO/2446/2012 (Portugal) funded by Fundação para a Ciência e Tecnologia (Portugal) and IGCP 597 “Amalgamation and Breakup of Pangaea: the type example of the supercontinent cycle” (UNESCO-IUGS). It is a contribution to project PEst-OE/CTE/UI4073/2014.
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Chichorro, M. et al. (2014). Provenance Analysis of the Late Ediacaran Basins from Southwestern Iberia (Série Negra Succession and Beiras Group): Evidence for a Common Neoproterozoic Evolution. In: Rocha, R., Pais, J., Kullberg, J., Finney, S. (eds) STRATI 2013. Springer Geology. Springer, Cham. https://doi.org/10.1007/978-3-319-04364-7_134
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