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113 ducted continental crust is not lost at convergent margins but recy- cled and reworked by the incorporation into melts of subducted material. This recycling is also warned during compressional peri- ods of this margin, which occurred during the closure of the basins upon superimposed contraction, and some parts of them were obducted and/or accreted to nearby sections of the arc system. In the regional background, the traditionally known as Cadomian Orogeny (c. 560–550 Ma) is linked with a period dominated by metamorphism at low-intermediate-P and strain (Eguíluz and Quesada, 1981; Eguiluz et al., 2000). In this context, a new pulse of magmatic activity with adakitic and strong silicic characteristic took place on the periphery of Gondwana mainland at c. 550 Ma (Fig. 13b, Valverde Metaigneous Complex). These geochemical characteristics equivalent to those obtained for the San Andrés rocks are consistent with a new episode of slab (crustal + mafic components) partial melting which also reflect an isotopic (Sr- Nd) mixing signature and appear driven by the mantle upwelling cycles. According to the U-Pb data included in this work, the last epi- sode of magma generation for this arc section was taken at c. 541 Ma. This age has been widely described through the Variscan Belt related to the Cadomian magmatism (e.g Linnemann et al., 2014) as well as with the generation of migmatitic domes that affected the previous igneous and sedimentary materials (Montero et al., 1999; Eguíluz, 1988). This change in the dynamic context of the active margin could facilitate an increase of the mag- matic activity within the mantle wedge, it is very likely occurred during a moment of tectonic relaxation after the c. 560–550 Ma margin accretion. This scenario is coherent with the more juvenile signature shown by the samples belonging to the Valle Real and Don Álvaro metaigneous complexes (Fig. 13c). The formation of these rocks at lower pressure in equilibrium with plagioclase, is coherent with this change of tectonic setting. Moreover, the more positive e Nd values and lower 87 Sr/ 86 Sr contents suggest an almost exclusive participation of metasomatized/modified mantle wedge, possibly favoured by an increase of the subduction angle of the slab. 7. Conclusions Taking into account the lithological, geochemical and geochronological constitution of the metaigneous complexes investigated in the preserved peri -Gondwana margin section in SW Iberia, it can be concluded that in this context the generation of magmas over time had a complex evolution. Different values of the subduction angle and subduction rate, different participation of a variably modified mantle source and also the combined role of old crustal and juvenile mafic materials driven by the slab incom- ing, are the key to understand the generation of magmas along the peri -Gondwanan margin. Furthermore, the origin of this crustal material is not always obvious, since in the studied section it is unlikely that the outcropping metasedimentary series (Monte- molín Formation of the Serie Negra) is the one involved, or the only one involved, in the generation of magmas. On the other hand, the magmatic evolution investigated in the Mérida Massif suggests that subduction erosion mechanisms have been underestimated as active processes in the dynamics and petrogenesis of arc mag- matism. Subduction erosion is a necessary process to explain the highly enriched mantle wedge and the formation of the magmas with adakitic affinity that appear in this magmatic arc at least between pre.602 Ma to c. 550 Ma. The long record of inherited ages in igneous zircons indicates that recycling of at least the studied arc section was continuous from c. 645–625 Ma without interruptions until c. 540 Ma. The dynamic evolution between the upper plate and the lithospheric mantle would have led to episodes with variable subduction ero- sion rates, recognizable through the changes produced in the geo- chemistry and isotopic sources of the different magmatic pulses preserved in the arc section. High rates of tectonic erosion favoured by low subduction angles lead to the generation of more silicic magmas with adakitic characteristics and isotopic signature (Nd- Sr) with a more cortical tendency. While roll-back episodes with an increase in the subduction angle would decrease the sediment rate from the tectonic recycling of the arc itself, thus generating typical calc-alkaline arc magmas with great influence from the metasomatized/modified mantle wedge, also reflected in the more juvenile isotopic (Nd -Sr) features. Surprisingly, the small section of the Cadomian arc that has been preserved in the Upper Unit of the Mérida Massif contains an excellent record of this cyclicality of petrogenetic and kinematic processes, not yet recognized in other sections of the European Cadomian basement, but which could foreseeably be done extensible to other regions with exten- sive preserved magmatism. CRediT authorship contribution statement Esther Rojo-Pérez: Conceptualization, Methodology, Formal analysis, Investigation, Resources, Writing – original draft, Writing – review & editing. Ulf Linnemann: Methodology, Formal analysis, Investigation, Writing – review & editing. Mandy Hofmann: Methodology, Formal analysis, Investigation, Writing – review & editing. José M. Fuenlabrada: Methodology, Formal analysis, Investigation, Writing – review & editing, Supervision. Johannes Zieger: Methodology, Formal analysis, Investigation, Writing – review & editing. Javier Fernández-Suárez: Investigation, Writing – review & editing, Supervision. Pilar Andonaegui: Investigation, Writing – review & editing, Supervision. Sonia Sánchez Martínez: Investigation, Writing – review & editing, Supervision. Rubén Díez Fernández: Conceptualization, Investigation, Writing – review & editing. Ricardo Arenas: Conceptualization, Investigation, Writing – review & editing, Supervision, Project administration, Funding acquisition. Declaration of Competing Interest The authors declare that they have no known competing finan- cial interests or personal relationships that could have appeared to influence the work reported in this paper. Acknowledgements We would like to thank Irene Novo-Fernández and Antonio García Casco for their company and interesting discussions in the field. I would also like to thank the technical members of the geol- ogy faculty of the Complutense University and the Senckenberg museum of Dresden. Significantly, I would like to thank the two anonymous reviewers for their constructive comments and sug- gestions that have helped to improve this manuscript and the Associate Editor of Gondwana Research, Yongjiang Liu, for his edi- torial support. Financial support has been provided by Spanish pro- jects CGL2016-76438-P and PID2020-112489GB-C21 (Ministerio de Ciencia e Innovación) and the associated grant BES-2017- 080200. Appendix A. Supplementary material Supplementary data to this article can be found online at https://doi.org/10.1016/j.gr.2022.04.011. E. Rojo-Pérez, U. Linnemann, M. Hofmann et al. Gondwana Research 109 (2022) 89–112 The Ediacaran arc section