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Realizando un estudio de la imaginería desde los orígenes a la actualidad y una investigación acerca de las consideraciones, novedades y aspectos importantes que se han desarrollado en los últimos años, a la par de los nacimientos de nuevos artistas, que pasaran a la historia como los grandes imagineros del presente siglo. Universidad de Sevilla. Grado en Bellas Artes

Trabajo presentado en el 2nd International congress on Permian and Triassic, celebrado en Casablanca (Marruecos), del 25 al 27 de abril de 2018, The Permian volcanism of the Eastern Rehamna massif (Western Meseta) displays two large outcrops: (i) Mechra Ben Abbou to the N and (ii) Benguerir to the S. The volcanism of Mechra Ben Abbou is often interbedded in Stephanian/Autunian sandstones/conglomerates (e.g., Gigout, 1952; Hoepffner, 1982; etc.), and appears as massive/fluidal andesitic lava flows and rhyolitic domes (e.g., the Bled Mekrach garnet-bearing rhyolitic dome). The thickness of these volcanics varies from a few tens of to 500 meters depending on their proximity to the effusive centers. The latter are situated either on/near the N40E lateorogenic dextral strike-slip Wadi Tarfa fault (Hoepffner, 1982) or along the half-graben bounding the Nahilat normal fault (e.g., El Kamel and Muller, 1987; Muller et al., 1990). In the southeastern Rehamna, east of the Benguerir City, there are also massive/fluidal lava flows (andesites) and isolated volcaniclastics overlying the Autunian conglomerates (similar to those of Mechra Ben Abbou). Rhyolitic domes intruding andesitic lava flows with mingling structures at their interface also occur, showing that the rhyolitic domes and the andesitic, ava flows were synchronous (Baudin et al., 2003). Another outcrop of andesitic lava flows overlies an hercynian outcrop (the Jbel Kharrou structure). Late-Hercynian microgranite and microdiorite dyke swarms and sill complexes are also present in Rehamna trending N-S to N30 (more rarely N90 to N130; Gigout, 1952; Hoepffner, 1982; etc.). They fill subvertical fractures (dykes) or more frequently cleavage (sills) with thicknesses varying from 1 to 10 m (reaching 20 m). They can be lenticular over a few meters or extend over several kilometers (Hoepffner, 1982). They were emplaced after the lower Permian molasses and before the Triassic: they intrude the Rehamna granite (268 ± 6 Ma; Mrini et al., 1992) and do not crosscut the Triassic cover. One of these dykes penetrates an overlapping contact affecting the first Permian detrital deposits of Formation 1. This overlapping fault is sealed by the last terms of this Formation (El Kamel and Muller, 1987, Muller et al., 1990). The microgranitic dykes display intraplate and calco-alkaline affinities and were emplaced at 285.4 ± 6.1 Ma (Baudin et al., 2003; Bensalah, 2012). We provide new insights into the mineralogy, geochemistry and geochronology of the Rehamna volcanism affecting the northwestern Gondwanaland Permian margin. The studied volcanics are typical orogenic calc-alkaline magmatism. The origin of garnet in the Bled Mekrach rhyolites (phenocrysts, xenocrysts, restites, or secondary reaction products) will be discussed on the basis of their textures, mineral relationships and chemistry data. We determined U-Pb zircon ages by Sensitive High-Resolution Ion Microprobe (SHRIMP) on the Bled Mekrach garnet-bearing rhyolitic dome. The sample BM 20 (GPS: 32°38'19.21"N, 7°45'5.23"W) yielded two predominant ages (611 ± 20 Ma and 285.3 ± 4.9 Ma): the last age is more concordant, being interpreted as the age of crystallization of rhyolites, while 611 Ma indicate inherited zircon that is sourced from the Pan-African crust under the Rehamna. The 285 Ma rhyolite age is very similar to that one obtained on the microgranitic dykes.

Trabajo presentado en el 2nd International Congress on Permian and Triassic, celebrado en Casablanca (Marruecos), del 24 al 27 de abril de 2018, The NE-SW Tsesdai basin (110 km to the SE of Rabat) is the third largest Late Palaeozoic continental trough in the northern Central Moroccan Meseta. It is, (i) the volcanic complex is Permian s.l. (post-Carboniferous and pre-Triassic, presumably Stephanian/Permian) a percept based on (a) the intrusion of rhyolites into the Visean deep marine siliciclastics of the basement (shark-fin rhyolitic dome of Ari el Mahsar extrusive and its satellite dykes); (b) the angular unconformity between the red detritic sediments and the Visean siliciclastics folded during the late Westphalian A; (c) the presence of reworked rhyolitic/andesitic pebbles in the red sediments of the Tsesdai basin and their absence in the detrital sediments of the Westphalian C/ D preserved nearby in the Sidi Kacem graben; (d) the angular unconformity between the Triassic and the red detritals; and (d) strike-slip fault that postdates the basin sedimentary/volcanic formations and predates the Triassic/Cenozoic. (ii) the distinction of 3 major volcanic pulses: the first one (mainly andesitic) predates the Permian series; witnesses of this pulse can still be observed in Tiddas, but most material is reworked in the conglomerates; the second pulse is synsedimentary, displays different petrographic characteristics, and it is remarkable for its andesitic lava flows interbedded with the detritals. The third pulse of intrusive rhyolitic dykes precedes the Ari el Mahsar rhyolitic dome emplacement and the dacitic flows. (iii) identification of three intra-permian tectonic events. The close relationship between volcanism and fracturation is obvious: dykes and effusive centers are located in relation with N40-N70 faults, mostly strike-slip. We present new insights on the petrology and geochronology of the Tsesdai Permian volcanism affecting the northwestern Gondwanaland margin. The studied volcanic has typical orogenic calc-alkaline signatures. For the last volcanic pulse we determined U-Pb ages of zircon by Sensitive High-Resolution Ion Microprobe (SHRIMP). The shark fin rhyolitic extrusive dome of Ari el Mahsar (sample ARM15/GPS: 33°39'51.48"N, 6° 4'2.06"W) yielded two predominant ages (603 ± 25 Ma and 286.4 ± 4.7 Ma): the young age is more concordant, being interpreted as the crystallization age of rhyolites, while

The area of Garrotxa (also known as the Olot area) represents the most recent (700,000-11,500 y) and better preserved area of magmatic activity in the NE Volcanic Province of Spain (NEVP). This region comprises a suite of intracontinental leucite basanites, nepheline basanites and alkali olivine basalts, which in most cases represent primary or nearly primary liquids. The geochemical characteristics of these lavas are very similar to the analogous petrologic types of other Cenozoic volcanics of Europe, which are intermediate between HIMU, DM and EM1. Quantitative trace element modeling, suggests derivation from an enriched mantle source by degrees of melting that progressively increased from the leucite basanites (∼4%) to the olivine basalts (∼16%). However, the relatively more variable Sr-Nd-Pb isotope signature of the magmas suggests the participation of at least two distinct components in the mantle source: (1) a sublithospheric one with a geochemical signature similar to the magmas of Calatrava (Central Spain) and other basalts of Europe; and (2) an enriched lithospheric component with a K-bearing phase present. The geochemical model proposed here involves the generation of a hybrid mantle lithosphere source produced by the infiltration of the sublitho spheric liquids into enriched domains of the mantle lithosphere, shortly before the melting event that generated the Garrotxa lavas. The available geological data suggest that the first enrichment event of the mantle lithosphere under the NEVP could be the result of Late Variscan mantle upwelling triggered by the extensional collapse of the Variscan orogen during the Permo-Carboniferous. By Jurassic/Cretaceous time, large-scale NNE-directed sublitho spheric mantle channeling of thermally and chemically anomalous plume material was placed under the Iberian Peninsula and Central Europe. However, the geodynamic conditions in the NEVP did not favor magmatism, which could not take place until the Cenozoic after extension started. This favored the second enrichment event of the mantle lithosphere by entrainment and storage of liquids generated in the sublithospheric plume material. After a relatively short period of time, as extension progressed, it triggered melting in the enriched portions of the mantle lithosphere during the Quaternary, generating the Garrotxa volcanism. © 2000 Elsevier Science B.V. All rights reserved., J.M.C. wishes to thank Dr M. Wilson for her support and encouragement during his stay at the University of Leeds. Also thanks to Dr R. Cliff, Dr J. Rosenbaum, P. Guise and R. Green for their help during the analytical work at the Geochronology Laboratory of the School of Earth Sciences at Leeds University (UK). The authors also wish to acknowledge the comments by Dr C. Chauvel on an earlier version of this manuscript and the helpful revisions made by Prof. Leeman and Prof. Verma. This work was financially supported by DGESIC project PB95-0107.

13 páginas, 5 figuras., [ES] La estructuración del cuadrante SE de la Península Ibérica (Béticas orientales y antepaís Ibérico), desde el Messiniense hasta la actualidad, ha sido el resultado de una serie compleja de eventos deformativos, relacionados con la actividad de una megazona de cizalla NNE-SSO en el SE de las Cordilleras Béticas (zona de cizalla Trans-Alborán-Palomares; TAPSZ). La deformación a lo largo de esta zona de cizalla se caracteriza por dos escenarios secuenciales diferentes: 1) períodos de concentración de esfuerzos, asociados con un frenado momentáneo del movimiento a lo largo de la TAPSZ, y con procesos de identación dirigidos hacia el NO, y 2) períodos de disipación de esfuerzos, que serían el resultado del escape lateral de bloques en forma de cuña, y del movimiento transcurrente renovado a lo largo de la TAPSZ. Estos eventos han generado campos de esfuerzos en el antepaís Ibérico, con una serie de consecuencias tales como el vulcanismo alcalino de Calatrava y Cofrentes, zonas de protorift, modificaciones de directrices estructurales previas, levantamientos/abombamientos localizados, y cambios en el régimen sedimentario de algunas cuencas., [EN] The structuration of the southeastern quarter of the Iberian Peninsula (eastern Betics and Iberian foreland), since Messinian time, was the result of a series of complex deformational events, as related to a major NNE-SSW sinistral shear zone disrupting the southeasternmost part of the Betic cordilleras (Trans-Alborán-Palomares shear zone; TAPSZ). Deformation along this shear zone was characterized by two differentiated and sequential scenarios: 1) periods of stress-build-up associated to momentary slip-obstruction along the TAPSZ, involving NW-directed indentation of the southeastern Iberian domain, and 2) periods of stress-release resulting from the lateral escape of wedge-shaped blocks, thus allowing full-scale strike-slip displacements along the TAPSZ. These events imposed compressional stress fields on the Iberian foreland, with a series of consequences such as alkaline volcanism in Calatrava and Cofrentes, protorift zones, changes in previous structural trends, localized uplift/doming processes, and changes in the sedimentary records of sorne basins., Financial support was provided by the Dirección General de la Política Científica through Project n.O PB87-0372.