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- Inspecting zircon populations of the Iberian Pyrite Belt: tracking the Cadomian record of the South Portuguese ZonePublication . Lains Amaral, João; Solá, A. Rita; M. Bento dos Santos, TelmoABSTRACT: The palaeogeographic location of the southernmost zone of the Iberian Massif, the South Portuguese Zone (SPZ), prior to the amalgamation of Pangaea is still a matter of debate. In this work, we attempt to track its palaeogeographic setting during the final stages of the Cadomian Cycle.
- Syn-rift unconformities punctuating the lower-middle Cambrian transition in the Atlas Rift, MoroccoPublication . Álvaro, J. Javier; Ezzouhairi, Hassan; Clausen, Sébastien; Ribeiro, Maria Luísa; Solá, A. RitaThe Cambrian Tamdroust and Bab n’Ali Volcanic Complexes represent two magmatic episodes developed in the latest Ediacaran–Cambrian Atlas Rift of Morocco. Their rifting pulses were accompanied by accumulation of volcanosedimentary edifices (dominated by effusive lava flows in the former and explosive acidic aprons in the latter) associated with active tilting and uplift. Sealing of their peneplaned horst-and-graben palaeotopographies led to the onset of distinct onlapping geometries and angular discordances capping eroded basements ranging from the Ediacaran Ouarzazate Supergroup to the Cambrian Asrir Formation. Previous interpretations of these discordances as pull-apart or compressive events are revised here and reinterpreted in an extensional (rifting) context associated with active volcanism. The record of erosive unconformities, stratigraphic gaps, condensed beds and onlapping patterns across the traditional “lower–middle Cambrian” (or Cambrian Series 2–3) transition of the Atlas Rift must be taken into consideration for global chronostratigraphic correlation based on their trilobite content.
- Geological correlation of Neves-Corvo Mine and Pomarão Antiform sequences (Iberian Pyrite Belt, Portugal)Publication . Albardeiro, Luís; Matos, João Xavier; Mendes, Márcia; Solá, A. Rita; Pereira, Zélia; Morais, Igor; Salgueiro, Rute; Pacheco, Nelson; Araújo, Vítor; Oliveira, José TomásABSTRACT: A geological correlation between Neves-Corvo (NC) and Pomarão antiforms is attempted. These regional scale major sequences are easily correlated but, at local scale, facies and age differences stand out. Stratigraphy includes: i) the Phyllite-Quartzite Group with identical paleogeography setting and similar late Famennian ages for uppermost levels (LL to LN miospore biozones in Pomarão and NC respectively). ii) the Volcano-Sedimentary Complex shows some discrepancyconcerning the age distribution of the felsic volcanic rocks (ca. 356-330for Pomarão and ca. 365-346 Ma for all NC area) while sediments rangefrom mid-Famennian to late Visean age (VH to NM Miospore Biozonefor NC). iii); the Baixo Alentejo Flysch Group (late Visean NM MiosporeBiozone onwards in NC), covering the previous sequences and beingslightly older than the uppermost volcanic rocks of Pomarão. Thecorrelation between these two structures is supported by geology andisotopic/biozone ages and favours exploration scenarios in both regions.
- CHRONIBERIA : ongoing development of a geochronological GIS database of IberiaPublication . Lopes, C.; Ferreira, A.; Chichorro, Martim; Pereira, Manuel Francisco Costa; Almeida, J. A.; Solá, A. Rita
- Les series volcaniques et volcanoclastiques Précambriènnes et Cambro-Ordoviciènnes des antiformes de Jbel Belkheit et de Jbel Bou Acila (Sud-Est du Massif Hercynien Central Marocain)Publication . Sabri, K.; Dahire, M.; Ouali, H.; Smaili, H.; Ntarmouchant, A.; Driouch, Y.; Ribeiro, Maria Luísa; Guimarães, Fernanda; Bento dos Santos, Telmo; Solá, A. Rita
- Intra-crustal recycling and crustal-mantle interactions revealed by oxygen isotopic composition of SW Iberia rocksPublication . Chichorro, Martim; Solá, A. Rita; Pereira, M. F.; Ferreira, A.; Sánchez-García, Teresa; Silva, J. B.; Williams, Ian S.; Armstrong, R. A.
- Provenance analysis of the Late Ediacaran basins from SW Iberia, Serie Negra Succession and Beiras Group : evidence for a common Neoproterozoic evolutionPublication . Chichorro, Martim; Solá, A. Rita; Pereira, Manuel Francisco Costa; Hofmann, Mandy; Linnemann, Ulf; Gerdes, Axel; Medina, Jorge; Lopes, L.; Silva, J. Brandão
- Different meanings for cummingtonite-hornblende association in plutonic rocks, Iberian Massif, Portugal [Poster]Publication . Solá, A. Rita; Moita, Patrícia; Santos, José Francisco; Neiva, A.M.R.; Ribeiro, Maria Luísa
- Proyecto GEO_FPI, cartografía de la Zona Surportuguesa (ZSP). Datos preliminares de un estudio geocronológico U-PbPublication . Díez-Montes, Alejandro; Matos, João Xavier; Valverde-Vaquero, Pablo; Solá, A. Rita; Beranoaguirre, Aratz; Albardeiro, Luis; Salgueiro, Rute; Morais, Igor; Montero, P.; López, M. T.RESUMEN: La ZSP es la unidad geotectónica más al suroeste del Orógeno Varisco y se consideran los siguientes dominios: Pulo do Lobo (Frasniense inferior y Fameniense superior), Faja Pirítica Ibérica (Givetiense-Viseense superior), Grupo Flysch Baixo Alen tejo (Viseense superior-Moscoviense superior) y Grupo Suroeste (Estruniense-Bashkiriense medio). En el proyecto GEO_FPI se ha prestado especial atención a la Faja Pirítica Ibérica, ya que es una de las provincias metalogenéticas más importantes del mundo, con depósitos de sulfuros masivos (VHMS) e importantes recursos de Cu, Zn, Pb, Ag, Au, Sn, In, Se, Ge. Se ha realizado un trabajo de campo en común en la región fronteriza de España y Portugal para permitir una mejor inte gración y correlación de los datos geológicos y cartográficos. Además, se han seleccionado 31 afloramientos donde se han recogido muestras para realizar un estudio de geocronología de U-Pb en circón. Los datos de edad obtenidos son importantes para restringir las estructuras geológicas de la Faja Pirítica Ibérica que albergan la mineralización masiva de sulfuros y, por otra parte, mejoran la visión geotectónica de toda la ZSP
- Chroniberia : the ongoing development of a geochronological GIS database of IberiaPublication . Lopes, C.; Ferreira, A.; Chichorro, Martim; Pereira, M. Francisco; Almeida, J. A.; Solá, A. Rita