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dominated by accretion. Local subduction polarity for this event is yet uncertain, but a S-directed com- ponent of dip has been deduced for the Cadomian accretionary thrusts. The regional background may provide further clues. The fore-arc sections were obducted onto more internal sections of the arc sys- tem (Díez Fernández et al . 2019), making the latter a thicker, more buoyant and less subductable pieces of lithosphere compared to the sections located farther inboard, thus favouring outboard-directed subduction polarity for the closure of more internal marginal basins (Figure 10(b)). A new pulse of exten- sion triggered the exhumation of deep-seated rocks, which was conducted by paired extensional faults that operated to the scale of the crust and brought upwards the roots of the former accretionary system over the cores of large antiformal (dome) structures (Figure 10(c)). Variscan deformation in the Mérida Massif reworked but did not reactivate major Cadomian structures such as accretionary faults and extensional detachments, which are now folded and cut by Variscan faults. In this regard, late Cadomian exten- sion can be observed as a transitional stage to the Variscan cycle, but most importantly, as a contributor to the stabilization (cratonization) of orogenic crust before subsequent deformation. Our work presents a case example that adds evi- dence to the notion that the lithosphere of the Iberian domain of Gondwana was constructed not only by the functioning of large-scale accretionary faults and tectonic transport of allochthonous ter- ranes during the Variscan Orogeny (e.g. Ribeiro et al . 2007; Martínez Catalán et al . 2009; Díez Fernández et al . 2016) but also during the Cadomian Orogeny (e.g. Abalos et al . 1991; Díez Fernández et al . 2019). The development of Ediacaran nappe stacks and the recognition of ophiolites involved in them open a new line of research towards the reconstruc- tion of the geodynamic evolution of the African mar- gin of Gondwana using data extracted from direct exposures of suture zones of its marginal basins. Acknow l edgments This work benefited from editorial work and comments of R. Stern. M.F. Pereira and an anonymous reviewer are thanked for constructive revisions, and S. Johnston for suggestions to an early version of the article. This work was supported by the Ministerio de Economía, Industria y Competitividad under Grant CGL2016-76438-P. A new Cadomian suture zone exposure has been discovered in Iberia. The suture zone is marked by a mafic-ultramafic ensemble, the Mérida Ophiolite. This suture zone was reworked but not reactivated during the Variscan cycle. The Mérida Ophiolite is one of the few Cadomian perigond- wanan ophiolites preserved. Data avai l abi l ity The data is directly accessible through the published text and figures. Disc l osure statement The authors declare that they have no conflict of interest. F unding This work was supported by the Ministerio de Economía, Industria y Competitividad, Gobierno de España [CGL2016- 76438-P]. O RCID Rubén Díez Fernández http://orcid.org/0000-0002-0379- 7970 Ricardo Arenas http://orcid.org/0000-0002-8229-4836 Esther Rojo-Pérez http://orcid.org/0000-0001-5780-6417 Sonia Sánchez Martínez http://orcid.org/0000-0003-0826- 5313 José Manuel Fuenlabrada http://orcid.org/0000-0001-6687- 8631 Author contribution RDF, RA and ERP designed the mapping campaign and carried it out. RDF delineated the maps (Figures 2 and 3) and draw the cross-sections (Figure 4). All authors discussed and interpreted the data and prepared the manuscript. References Abalos, B., 1987, Tectónica y metamorfismo en el Núcleo de Almadén de la Plata (Sevilla, Zona de Ossa-Morena), [Ph.D.]: Universidad del País Vasco, p. 174 p. Abalos, B., Gil Ibarguchi, J.I., and Eguiluz, L., 1991, Cadomian subduction, collision and Variscan transpression in the Badajoz-Cordoba Shear Belt: Southwest Spain: Tectonophysics, v. 199, p. 51–72. Abati, J., Arenas, R., Díez Fernández, R., Albert, R., and Gerdes, A., 2018, Combined zircon UPb and LuHf isotopes study of magmatism and high-P metamorphism of the basal allochthonous units in the SW Iberian Massif (Ossa-Morena complex): Lithos, v. 322, p. 20–37. doi:10.1016/j. lithos.2018.07.032. Arenas, R., Martínez Catalán, J.R., Sánchez Martínez, S., Díaz García, F., Abati, J., Fernández-Suárez, J., Andonaegui, P., and Gómez Barreiro, J., 2007, Paleozoic ophiolites in the 16 R. D. FERNÁNDEZ ET AL. &KDSWHU