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112 Fig. 13. Plate profiles depicting stages in the evolution of the Ediacaran arc of the Mérida Massif (SW Iberia). These stages integrate magma sources according to isotopic and geochemical features along with dynamic evolution over the period pre-602 to 550 Ma. The model includes: (a) the generation before c. 602 Ma of calc-alkaline mafic magmas (metabasites of Montemolín Formation) derived from the mantle wedge modified by transferring of cortical signature through subduction erosion; (b) deep melting of crustal material generated by subduction erosion, variably mixed with melted mafic rocks, generates magmas with adakitic signature (San Andrés and Valverde metaigneous complexes) between c. 602–550 Ma, likely favoured by low subduction angle; (c) change in the subduction angle driven by a roll-back limited the subduction of crustal material and favoured the generation of common calc-alkaline magmas (Don Álvaro and Valle Real metaigneous complexes) at c. 540 Ma. Subduction erosion mechanism and diapirs morphology after Smithies et al. (2003), Castro et al. (2013, 2021) and Straub et al. (2020). This Cadomian volcanic arc was built in the periphery of the West African Craton (WAC). E. Rojo-Pérez, U. Linnemann, M. Hofmann et al. Gondwana Research 109 (2022) 89–112 &KDSWHU