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Metamorphic basements are usually considered rigid and isotropic at a large scale. However, basements contain inherited weaknesses that may potentially accommodate superimposed contraction (e.g., fault reactivation), and that favor fold nucleation (e.g., penetrative foliations). If these conditions are met, what could be the factors that impede the development of basement folds or their recognition? Actual basement folding is rarely documented, especially for large dimensions. Here we provide a case example, discussed from the perspective of structural analysis of surface data and sustained by geophysical data. The basement of the Spanish‐Portuguese Central System is defined by an Alpine mega‐fold (Hiendelaencina Antiform) that trends parallel to this mountain range and affects the basement and its sedimentary cover, collectively. The wavelength of this fold matches or even surpasses the thickness of the crust that hosts it (36–41 km). The Moho under this mega‐fold is displaced by an Alpine fault that accounts for incipient intraplate continental subduction. The topography of the mantle may reflect an up‐warping compatible with the mega‐fold observed on the surface. Mega‐folding is observed in the hanging wall of the Berzosa Fault, which emerges as a SE‐dipping, Variscan (Paleozoic), extensional fault reactivated as a basal decollement upon Alpine (Cenozoic) contraction. The mega‐fold was formed after well‐oriented planar anisotropies in the basement (foliation and bedding). The development of this fold was assisted by heterogeneous shearing (coeval thrusting) plus the buttressing effect of pre‐existing, near‐vertical, crustal‐scale faults (Somolinos and Somosierra), which inhibited slip‐upsection through the basal decollement (Berzosa Fault). The basement of the easternmost part of the Spanish‐Portuguese Central System is affected by an Alpine mega‐foldThe mega‐fold has a wavelength that matches the thickness of the crust and is soled by a thrust that displaces the MohoMega‐folding occurred in a context of incipient intraplate subduction ruled by Variscan structural inheritance in the basement The basement of the easternmost part of the Spanish‐Portuguese Central System is affected by an Alpine mega‐fold The mega‐fold has a wavelength that matches the thickness of the crust and is soled by a thrust that displaces the Moho Mega‐folding occurred in a context of incipient intraplate subduction ruled by Variscan structural inheritance in the basement

The Calzadilla Ophiolite is an ensemble of mafic and ultramafic rocks that represents the transition between lower crust and upper mantle of a Cadomian (peri‐Gondwanan) fore arc. Mapping and structural analysis of the ophiolite demonstrates that it was obducted in latest Ediacaran times, because the Ediacaran‐Early Cambrian sedimentary series (Malcocinado Formation) discordantly covers it. The ophiolite and emplacement‐related structures are affected by Variscan deformation (Devonian‐Carboniferous), which includes SW verging overturned folds (D1) and thrusts (D2), upright folds (D3), extensional faults (D4), and later faults (D5). These phases of deformation are explained in the context of Variscan tectonics as the result of the progressive collision between Gondwana and Laurussia. Qualitative unstraining of Variscan deformation reveals the primary geometry of Ediacaran‐Cambrian structures and uncovers the generation of east verging thrusts as responsible for the primary obduction of the Calzadilla Ophiolite. Restoration of planar and linear structures associated with this event indicates an Ediacaran, east directed obduction of the ophiolite, that is, emplacement of the Cadomian fore arc onto inner sections of the northern margin of Gondwana. According to regional data, the obduction separates two extension‐dominated stages in the tectonic evolution of the African margin of northern Gondwana preserved in southern Europe. Preobduction extension brought about the onset and widening of fore‐arc and back‐arc basins in the external part of the continent, while postobduction extension facilitated the formation of extensional migmatitic domes, an oceanward migration of back‐arc spreading centers across peri‐Gondwana, and the eventual opening of a major basin such as the Rheic Ocean. The Calzadilla Ophiolite is a fore‐arc ensemble obducted onto a section of a peri‐Gondwanan arc in latest Ediacaran timesOphiolite obduction was directed to the ESE (present‐day coordinates), following a vector directed to mainland GondwanaObduction preceded back‐arc and fore‐arc spreading in peri‐Gondwana and was followed by the onset of extensional domes and rifting

The Cadomian Orogeny produced a subduction‐related orogen along the periphery of Gondwana and configured the pre‐Variscan basement of the Iberian Massif. The architecture of the Cadomian Orogen requires detailed structural analysis for reconstruction because of severe tectonic reworking during the Paleozoic (Variscan cycle). Tectonometamorphic analysis and data compilation in SW Iberia (La Serena Massif, Spain) have allowed the identification of three Cadomian deformation phases and further constrained the global architecture and large‐scale processes that contributed to the Ediacaran building and early Paleozoic dismantling of the Cadomian Orogen. The first phase (DC1, prior to 573 Ma) favored tabular morphology in plutons that intruded during the building of a continental arc. The second phase (DC2, 573–535 Ma) produced an upright folding and contributed to further crustal thickening. The third phase of deformation (DC3, ranging between ∼535 and ∼480 Ma) resulted in an orogen‐parallel dome with oblique extensional flow. DC1represents the crustal growth and thickening stage. DC2is synchronous with a period of crustal thickening that affected most of the Gondwanan periphery, from the most external sections (Cadomian fore‐arc) to the inner ones (Cadomian back‐arc). We explain DC2as a consequence of flat subduction, which was followed by a period dominated by crustal extension (DC3) upon roll‐back of the lower plate. The Ediacaran construction of the Cadomian Orogen (DC1and DC2) requires ongoing subduction beneath Gondwana s.l., whereas its dismantlement during the Early Paleozoic is compatible with oblique, sinistral convergence. Three Cadomian deformation phases affected the upper plate of a peri‐Gondwanan arcCrustal thickening and thinning resulted from flat subduction and roll backThe Cadomian Orogeny was ruled by sinistral plate convergence in Iberian Gondwana Three Cadomian deformation phases affected the upper plate of a peri‐Gondwanan arc Crustal thickening and thinning resulted from flat subduction and roll back The Cadomian Orogeny was ruled by sinistral plate convergence in Iberian Gondwana

El lenguaje se constituye en una variable importante en el desarrollo de la habilidad comunicativa de todo ser humano; su desarrollo depende, entre otros aspectos, de las oportunidades dadas por el contexto. Dentro de estas oportunidades, se encuentran los servicios de fonoaudiología, en donde los procesos de intervención se derivan de una evaluación. Dicho proceso evaluativo en la población con discapacidad cognitiva presenta limitaciones por la falta de pruebas objetivas, válidas y confiables que permitan determinar las características de su situación comunicativa. El objetivo de esta investigación fue establecer la validez (de contenido y constructo) y la confiabilidad de una prueba para evaluar comportamientos lingüísticos en población con discapacidad cognitiva de la ciudad de Medellín. Para ello se utilizó un método analítico inferencial relacionado con la validación de instrumentos de medición; la validez de contenido se realizó por juicio de expertos; participaron 13 fonoaudiólogos con experiencia en la atención a la población objeto, quienes evaluaron la prueba bajo los criterios de pertinencia y suficiencia. Para establecer la validez de constructo confirmatorio se utilizó el análisis factorial y se determinó la confiabilidad del instrumento a partir de la consistencia interna de constructo y la prueba test-retest; participaron 75 usuarios. Los resultados del presente estudio avalan la consistencia interna y la estabilidad de la prueba, su validez de contenido y de constructo.

A correlation between allochthonous units exposed in the NW Iberian Massif and the southern Armorican Massif is carried out based on lithological associations, structural position, age and geochemistry of protoliths and tectonometamorphic evolution. The units on both sides of the Bay of Biscay are grouped into Upper, Middle and Lower allochthons, whereas an underlying allochthonous thrust sheet identified in both massifs is referred to as the Parautochthon. The Lower Allochthon represents a fragment of the outermost edge of Gondwana that underwent continental subduction shortly after the closure of a Palaeozoic ocean which, in turn, is represented by the Middle Allochthon. The latter consists of supra-subduction ophiolites and metasedimentary sequences alternating with basic, mid-ocean ridge basalt (MORB)-type volcanics, with inheritances suggesting the proximity of a continental domain. Seafloor spreading began at the Cambro-Ordovician boundary and oceanic crust was still formed during the Late Devonian, covering the lifetime of the Rheic Ocean, which is possibly represented by the Middle Allochthon. The opening of the oceanic domain was related to pulling apart the peri-Gondwanan continental magmatic arc, which is represented by the Upper Allochthon.

Detrital U-Pb laser ablation inductively coupled plasma mass spectrometry zircon ages from six siliciclastic samples from the lower allochthon of NW Iberia are analysed to constrain their maximum sedimentation age and provenance, and to evaluate the connections to the adjacent tectonostratigraphic domains. Deposited in the external sections of the Gondwana platform, their maximum depositional age is latest Neoproterozoic (c. 560 Ma). Comparison of the age populations of the lower allochthon with those of the rest of the allochthonous and autochthonous units of NW Iberia suggests that the terranes located in the footwall of the Variscan suture should not be considered as exotic elements, but as contiguous pieces of the same continental margin transported onto the adjacent Gondwana mainland in Variscan times. The data are in agreement with the regional trend defined by the drop in Early Neoproterozoic and Mesoproterozoic zircon content upward in the tectonic pile, which had been previously proposed as a marker of proximity to the eastern part of the West African Craton. Based on the age spectra, the palaeoposition for the time of sedimentation is placed in northern Africa, between the West African and Saharan cratons. Particular attention is paid to the occurrence of an Early Neoproterozoic input, probably derived from the Pan-African Hoggar suture. [ABSTRACT FROM AUTHOR]

In the Purrido Ophiolite (Cabo Ortegal Complex), new U-Pb zircon dating of the amphibolite G03-8 (by laser ablation inductively coupled plasma mass spectrometry) confirms the existence of a dominant Mesoproterozoic zircon population with a refined age of 1155 ± 14 Ma. However, the U-Pb zircon dating of two more amphibolite samples (by sensitive high-resolution ion microprobe) has provided new ages of 395 ± 3 Ma and 395 ± 2 Ma, respectively, interpreted as the crystallization age. Hf isotope data for zircon show that most of the Devonian zircons crystallized from a juvenile depleted mantle source. The Mesoproterozoic zircons have relatively juvenile Hf isotopic composition reflecting some influence of an older component. A few Devonian zircon crystals show evidence of mixing with an older component represented by the Mesoproterozoic zircons. The whole-rock Sm-Nd isotope data indicate an important heterogeneity in the composition of the Purrido amphibolites, only compatible with the generation of their protoliths from two sources. We interpret these puzzling data as resulting from the mixing of a Devonian mantle-derived magma with a Mesoproterozoic basement. These new data provide new perspectives in the interpretation of the most common ophiolites across the Variscan suture in Europe. [ABSTRACT FROM AUTHOR]

Geological mapping, structural data, and analytical modeling by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791supported that the Central Unit belonged to a rootless Devonian suture zone contiguous to the SW of its exposure and under the upper section of the footwall to the Azuaga Fault. Late exhumation of the Central Unit was via extrusion from the upper‐middle crust under inclined triclinic sinistral transpression, which favored upright folding of the suture zone. Azor and coworkers argue that the upright folds that affect the Central Unit are local, despite geological maps and structural data demonstrate they are km‐scale and occur all across the Central Unit. Besides ignoring structural data regarding the kinematics of the Azuaga Fault, Azor et al. (2022), https://doi.org/10.1029/2021TC006982fail to recognize the net upthrown movement of the NE side of the Azuaga Fault, as the Central Unit in that side is juxtaposed against syn‐orogenic strata that rest unconformably onto other metamorphic units in the SW side of the fault. Seismic data that image the Central Unit as a NE‐dipping rock package is used as an argument against the proposal by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791. However, the section of the Central Unit those data account for, are from a different part of the Central Unit, the real dip of some structures in the seismic image is not properly interpreted, and the model by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791is compatible with a Central Unit that also dips to the NE. Overall, the model proposed by Díez Fernández et al. (2021), https://doi.org/10.1029/2021tc006791remains valid. The Central Unit belonged to a rootless Devonian suture zone contiguous to the SW of its exposureThe late exhumation of the Central Unit was via extrusion from the upper‐middle crust under inclined triclinic sinistral transpressionLate exhumation favored upright folding of the suture zone, exposing it in a tectonic window at the core of the Ossa‐Morena Complex The Central Unit belonged to a rootless Devonian suture zone contiguous to the SW of its exposure The late exhumation of the Central Unit was via extrusion from the upper‐middle crust under inclined triclinic sinistral transpression Late exhumation favored upright folding of the suture zone, exposing it in a tectonic window at the core of the Ossa‐Morena Complex

The ophiolites preserved in the Variscan suture of NW Iberia (Galicia) show a broad variability in lithology, geochemistry and chronology. This wide variety rules out the simplest plate tectonic scenario in which these ophiolites would have been exclusively related to the oceanic domain closed during the final Pangaea assembly, that is the Rheic Ocean. The ophiolitic units from Galicia also provide important data about the palaeogeography immediately preceding the opening of this ocean, and some information about pre-Gondwanan supercontinent cycles. Six different ophiolites can be distinguished in the allochthonous complexes of Galicia: the Purrido, Somozas, Bazar, Vila de Cruces, Moeche and Careón units. The Purrido Ophiolite is constituted by metagabbroic amphibolites with igneous protoliths dated at 1159±39 Ma (Mesoproterozoic), and geochemical affinities typical of island-arc tholeiites. These mafic rocks can be interpreted as one of the scarce members of the pre-Rodinian ophiolites, and they were probably generated in a back-arc setting in the periphery of the West African Craton. The Somozas Ophiolitic Mélange consists of a mixing of submarine volcanic rocks (pillow-lavas, submarine breccias, pillow-breccias, hyaloclastites), diabases, gabbros, microgabbros, diorites and granitoids, surrounded by a matrix of serpentinites or, less frequently, phyllites. Two granitic samples from this mélange yield U–Pb ages ranging between c. 527 and 503 Ma (Cambrian), which together with the characteristic arc signatures obtained in all the studied igneous rocks suggest that this ophiolite was generated in a peri-Gondwanan volcanic arc. The Bazar Ophiolite is formed by different tectonic slices with high temperature amphibolites, granulites, metagabbros and ultramafic rocks. The amphibolites are the most abundant rock type and show typical N–MORB compositions with igneous protoliths dated at 498±2 Ma (Cambrian). The high-temperature metamorphism affecting some parts of the unit has been dated at c. 480 Ma (lower Ordovician), and it is considered to be related to the development of an oceanic accretionary complex under the volcanic arc represented by the upper units of the allochthonous complexes of Galicia. Considering the most common palaeogeographic reconstructions for the Cambrian period, it is suggested that the oceanic lithosphere represented by the Bazar Ophiolite was formed into the peri-Gondwanan oceanic domain prior to the rifting of the Avalonian microcontinent, that is the Iapetus–Tornquist Ocean. According to current data about the Vila de Cruces Unit, it can be interpreted as a composite terrane, whose lithologies have U–Pb ages ranging from 1176–497 Ma, but constituted by metaigneous rocks with arc signatures. This dataset has been interpreted in relation to the development of a back-arc basin around the Cambrian–Ordovician limit, involving a Mesoproterozoic basement and the reactivation of a former suture. The opening of this back-arc basin can also be identified as the birth of the Rheic Ocean, and probably it would also include the lithological succession belonging to the Moeche Unit, although its basic rocks exhibit compositions with more oceanic character. Finally, the Careón Ophiolite includes remnants of an oceanic lithosphere generated in a supra-subduction zone setting at 395±2 Ma (middle Devonian). This ophiolite was formed in a contractive Rheic Ocean, shortly preceding the closure of this ocean. This is the only ophiolite in Galicia that can be related to mature stages of the Rheic Ocean, although as it is commonly observed in other regions the N–MORB crust is not preserved. This common oceanic crust has disappeared during subduction, probably in an intra-oceanic setting and during the generation of the igneous section preserved in the Careón Ophiolite.

The tectonothermal evolution of a polyorogenic terrane in the Variscan belt of NW Spain has been constrained by 40Ar/39Ar laserprobe incremental heating experiments on mylonitic fabrics developed in major structures. Transitional levels between HP-HT and IP upper units in the Órdenes Complex where metamorphic and structural records demonstrate two cycles of burial and exhumation were selected for dating. Two groups of ages have been defined: (1) Silurian-Early Devonian, obtained from mylonites of the Fornás extensional detachment, here considered as the minimum age for the start of tectonic exhumation of the HP-HT units and an upper age-limit for the HP-HT event itself; (2) Early to Mid-Devonian, from structures related to the Variscan convergence in the area, which include top-to-the-east thrusts and extensional detachments. A single, younger Carboniferous age obtained from the uppermost allochthonous sequences possibly reflects the final stages of emplacement of the allochthonous complexes. Our data indicate a polyorogenic character for a part of the Iberian allochthonous complexes, including Variscan (sensu stricto) and Early Variscan convergence, as well as an older, Early Palaeozoic cycle. [ABSTRACT FROM AUTHOR]

Suture zones are key to understand collisional orogens, but not all the remains of subduction leading to collision occur in the root of the suture. The Azuaga Fault bounds a Devonian suture zone known as Central Unit. This fault is a steeply NE‐dipping, Variscan strike‐slip fault with left‐lateral and reverse oblique slip components formed during sinistral transpression in the Pennsylvanian. Motion along this fault was coeval with folding and fabric development in both its hanging wall and footwall, and also with the Matachel Fault. Tectonic flow associated with the Azuaga Fault shows high‐vorticity, explaining the exhumation of a flat‐lying Devonian suture zone via WNW‐plunging extrusion from the upper‐middle crust under inclined triclinic transpression during ENE‐WSW convergence. The exposed basal contact of the Central Unit is not the root zone of a Variscan suture zone, but instead is a NE‐dipping breaching fault that cuts across the suture zone that is contiguous to the SW under the upper section of the footwall. The peri‐Gondwanan terrane between the Central Unit and the South‐Portuguese Zone of the Iberian Massif (most of the Ossa‐Morena Zone) is underlain by a Devonian suture, implying it is a continental allochthon. Variscan suture zones in Europe are affected by strike‐slip faults. In our case, this pattern implies the location of suture zone exposures and location of its root are different. Suture zones and strike‐slip faults are common in orogens and analysis of their relationships may lead to relocation of suture zone roots and re‐thinking of upper and lower plates. Azuaga Fault is a Variscan, high‐angle, NE‐dipping, strike‐slip fault with left‐lateral and reverse‐oblique slip formed under transpressionThe current basal contact of the Central Unit is not the root zone of a Variscan (Devonian) suture zoneThe Gondwanan terrane between Central Unit and almost the South‐Portuguese Zone is underlain by a suture zone equivalent to the Central Unit Azuaga Fault is a Variscan, high‐angle, NE‐dipping, strike‐slip fault with left‐lateral and reverse‐oblique slip formed under transpression The current basal contact of the Central Unit is not the root zone of a Variscan (Devonian) suture zone The Gondwanan terrane between Central Unit and almost the South‐Portuguese Zone is underlain by a suture zone equivalent to the Central Unit

The kinematics of the basal allochthon in the SW of the Órdenes Complex is analysed to constraint its evolution during collisional and postcollisional stages of the Variscan orogeny. Two distinct sequences have been identified in the basal allochthon of this sector: the upper and lower sequences, in close correlation with the subdivision of the basal allochthon in the Malpica-Tui Complex. Three main tectonic episodes have been established in the basal allochthon: a high-pressure event related to continental subduction, a mesozonal event of regional exhumation by thrusting and recumbent folding, and a regional-scale extensional episode that resulted in the development of the Bembibre-Pico Sacro detachment system. The Bembibre-Pico Sacro system rejuvenated pre-existing shear zones, whose weakness favoured the nucleation of the detachments. Shear zones associated with the detachments overprinted the previous tectonic fabrics under conditions ranging from lower amphibolite to greenschist facies, and with heterogeneously distributed ductile to brittle deformation. The detachment system is coeval with late orogenic collapse and widespread magmatism, and represents its upper crustal expression. It correlates with mid- and lower crustal flow and the development of gneiss domes at depth in such a way that the basal allochthon can be considered a rheological boundary between the more rigid allochthonous sequences above and the more viscous Schistose Domain and autochthon below. [ABSTRACT FROM AUTHOR]