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- A first appraisal on copper sources for Chalcolithic settlements in southern Portugal using Pb isotope analysisPublication . SOARES, António; Valério, Pedro; Gomes, Susana Sousa; Mataloto, Rui; Soares, Sofia; Silva, R.J.C.; Soares, Rui M.ABSTRACT: This work presents the first provenance study on copper in use by 3rd millennium BC communities in southern Portugal. Copper ores from small mines and copper artefacts from Chalcolithic settlements were subjected to Pb isotope analysis. Some of Pb isotope ratios obtained in ores from the Ossa-Morena Zone, but also from the South Portuguese Zone, evince the existence of deposits with highly radiogenic Pb, which was previously considered rare in the Iberian Peninsula. Pb isotope ratios of artefacts were compared with Pb isotope fields of closer geological/tectonostratigraphic zones, namely the South Portuguese Zone, Ossa-Morena Zone and Central Iberian Zone. The assessment suggests that most artefacts were produced with copper from the Ossa-Morena Zone. Nevertheless, a flat axe of the Três Moinhos settlement is a remarkable exception due to its highly radiogenic Pb signature, which only has parallels in the Iberian Peninsula on copper ores of the Chalcolithic mines of La Profunda and El Milagro (northern Spain). Consequently, this flat axe constitutes the first indication of a possible long-distance trade of copper between the Cantabrian region and southwestern Iberian Peninsula during the 3rd millennium BC.
- Contributo do acompanhamento das grandes obras de engenharia para a cartografia geológica : Caso de estudo do Corredor Internacional SulPublication . Morais, Igor; Albardeiro, Luís; Gonçalves, Pedro; Soares, S.; Solá, A. Rita; Dias, Ruben Pereira; Ressurreição, Ricardo; Castro-Pina, M.; Serra, B.; Pereira, Zélia; Mendes, MárciaSUMMARY: The follow up of new railway works, which will be part of the International South Corridor (Corredor Internacional Sul”, allowing the privileged access to new Ossa-Morena Zone outcrops, contributes to refine detailed geological mapping, as part of LNEG's mission. Along the different sections of the railway line, systematic geological sampling was carried out for petrographic, geochronological and paleontological studies. In addition, photographic record and three-dimensional modeling of the main slopes were performed using a drone. This methodology allows the construction of an information repository that can be consulted long after the works have been concluded and the outcrops become inaccessible. Besides the accuracy improvement of the geological contacts of the Ossa-Morena Zone rocks, the preliminary results confirmed the extent of Miocene debris flow sedimentation (conglomerates) and subsequent calcretization, and has identified new mineral occurrences.
- Arquivos de sondagens: responsabilidade científica e cultural. O exemplo da prospeção de lignites em Rio MaiorPublication . Soares, S.; Brandão, José Manuel Moraes ValeRESUMO: A Litoteca do LNEG é uma importante infraestrutura de apoio à investigação e ao desenvolvimento, onde se encontram arquivados cerca de 600 km de testemunhos de sondagens das diversas regiões do país. No presente artigo será efetuado o enquadramento relativo às sondagens de prospeção realizadas na região de Rio Maior durante os tempos áureos de prospeção de lignite nesta área, realçando os registos existentes no LNEG e a importância da sua manutenção para a Ciência e a Cultura.
- Remanescências do Império Português em África. As amostras geológicas de Capelo e Ivens revisitadas (1884-1885)Publication . Brandão, José Manuel Moraes Vale; Soares, S.; Brito, StelaRESUMO: No presente artigo, revisita-se a coleção de amostras geológicas recolhidas pelos oficiais da Marinha Portuguesa Hermenegildo Capelo e Roberto Ivens, durante a famosa viagem De Angola á Contracosta. Confiadas à Comissão dos Trabalhos Geológicos, aquando do regresso dos exploradores, as amostras foram classificadas por Nery Delgado e Alfredo Bensaúde, tendo sido incorporadas no acervo do Museu Geológico e, na década de 1990, transferidas para a Litoteca do LNEG, polo de Alfragide, onde foram objeto de um trabalho de reacondicionamento e inventário, revisto e ampliado recentemente. Para além do seu valor enquanto testemunho das explorações científicas empreendidas pelos portugueses em solo africano, estas amostras, analisadas em conjunto com o texto homónimo assinado pelos dois exploradores, ilustram muitas das diferentes litologias atravessadas, dos cratões africanos e das orlas sedimentares.
- Trailing Capelo and Ivens 2nd African journey, through their geological samplesPublication . Brandão, José Manuel Moraes Vale; Soares, S.
- Geodiversidade no troço médio do rio Guadiana, argumentos para um futuro Geoparque no território de Mértola, Serpa, Moura e BarrancosPublication . Matos, João Xavier; Dias, Ruben Pereira; Pereira, Zélia; Ressurreição, Ricardo; Soares, S.; Mendes, Márcia; Albardeiro, Luís; Gonçalves, Pedro; Santos, Sara; Piçarra, José ManuelSUMMARY: The region of Mértola, Serpa, Moura and Barrancos, located in the middle section of the Guadiana River presents a distribution of geosites of great scientific value, constituting the argument to a future Geopark. The studied territory includes the Ossa-Morena (OMZ) and South Portuguese (SPZ) geological sequences, the tectonic boundary between these two variscan domains, the geomorphology conditioned by Alpine tectonics, the Guadiana, Ardila and Chança rivers incision and differential erosion of quartzites, dolomites and marbles. Significant geological heritage is also present in the SPZ Iberian Pyrite Belt VMS and OMZ copper deposits. The Guadiana territory presents a typical landscape and exceptional geosites in a natural habitat (e.g. Pulo do Lobo waterfalls). In total, 50 geosites were considered in 6 regions: Barrancos-Ardila, Ficalho, Serpa-Pias-Moura, Alcaria, Guadiana and São Domingos. The future project of Geopark will be planned by the four municipalities considering geoconservation plans and regional sustainable policy.
- Calcretos da região de Elvas : Estudo preliminarPublication . Soares, S.; Dias, Ruben Pereira; Ressurreição, Ricardo; Morais, Igor; Albardeiro, Luís; Gonçalves, Pedro; Solá, A. Rita; Castro-Pina, M.SUMMARY: The construction of a new railway in NE Alentejo crossing the Ossa Morena Zona allowed new detailed studies focused on the geological units and the structure of the area. In the Elvas region, the Miocene is represented by a coarse conglomerate covered by sandy mudstones. The conglomerate is coarser near the Messejana fault, where it is also tilted. Its deposition is probably related to the Alpine reactivation of the fault. The sediments and the basement rocks are strongly affected by Miocene calcretization. A chemical characterization of calcrete along vertical profiles was done with portable x-ray fluorescence equipment. The preliminary results show a decrease in CaO content upwards and an increase in SiO2.