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Fig. 7. f Sm/Nd vs ε Nd (T) diagram (McLennan and Hemming, 1992) showing the isotopic composition of the Late Ediacaran siliciclastic rocks. Long lived magmatic arc (c. 750-500 Ma) Ediacaran peri-Gondwanan series Neoproterozoic orogens Cratons and meta-cratons Active long-lived subduction zone Back-arc basin c. 540 Ma Avalonian - Cadomian Magmatic Arc 0.54-1.1 1.8-2.2 2.7-2.9 3.1-3.4 Ga 0.54-1.2 1.6-2.3 2.6-2.8 3.0-3.3 Ga 0.54-0.7 1.0-1.35 1.45-1.75 2.5-3.1 Ga 0.55-0.65 0.9-1.1 1.65-1.85 2.45-2.7 Ga 0.55-0.65 0.9-1.1 1.65-1.85 2.45-2.7 Ga Zircon ages from the cratons Amazonian Craton West African Craton Sahara Meta-Craton Congo Craton Kalahari Craton Arabian Nubian Shield Indian Shield East Antartic Shield Australian Shield Peri-Gondwanan Ocean South Pole CIZ OMC Serie Negra Lower Alcudian Tuareg Shield Fig. 8. Paleogeographic reconstruction of Gondwana at c. 540 Ma showing the location inferred for the deposition of the Late Ediacaran series of the southern Central Iberian Zone (Lower Alcudian) and Obejo Valsequillo Domain (Ossa-Morena Complex, Serie Negra) in the periphery of the African margin. Paleogeography of Gondwana based on von Raumer and Stampfli (2008), Díez Fernández et al. (2010), Fernández-Suarez et al. (2014), Albert et al. (2015a) and Arenas et al. (2018) . Numbers in squares are zircon ages in Ga, from Avigad et al. (2012), Linnemann et al. (2014) and Morag et al. (2012). OMC: Ossa – Morena Complex ; CIZ: Central Iberian Zone. E. Rojo-Pérez et al. 3UHFDPEULDQ 5HVHDUFK ² Contrasting isotopic sources: CIZ - OMC boundary