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African margin of Gondwana (Bandrés et al . 2004; Linnemann et al . 2008; Fuenlabrada et al . 2012; Sánchez Lorda et al . 2014; Henriques et al . 2015; Orejana et al . 2015; Arenas et al . 2018; Rojo-Pérez et al . 2019). This section of the margin was subjected to alter- nating stages of compression and extension, depending on the coupling state between upper and lower plate (Díez Fernández et al . 2019). This resulted in the opening, closure and obduction of different sections of supra- subduction marginal basins located in the peri- Gondwanan realm (Figure 10). The Mérida Ophiolite could represent pieces of transitional to oceanic lithosphere of a marginal basin that opened during a stage of extension inboard respect to the peri-Gondwanan fore-arc (Figure 10(a)). The marginal basins were closed upon superimposed contraction, and some parts of them were obducted and/or accreted to nearby sec- tions of the arc system (Figure 10(b)). Given the deep- seated nature of the rocks of the Mafic-ultramafic Unit (peak-P around 1.2 GPa), the Ediacaran rocks of the Mérida Massif were involved in a setting Figure 10. Model showing the Ediacaran and Cambrian tectonic evolution of the Iberian margin of northern Gondwana (edited from Díez Fernández et al . 2019). The model conceives (a) the development of a fore-arc basin (Arenas et al . 2018) and other supra- subduction marginal basins (intra-arc or back-arc) towards inner sections of a continental arc system during the Ediacaran period, followed by (b) the closure of these basins upon superimposed compression over the upper plate. (c) A new stage of lithosphere extension is considered responsible for the onset of migmatite/gneiss-cored domes, while exhumation of deep-seated rocks was assisted by (paired) low-angle normal faults (e.g., Trujillanos and Carija detachments). Palaeogeographic coordinates. INTERNATIONAL GEOLOGY REVIEW 15 Tectonostratigraphy of the Mérida Massif