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- Litoteca do LNEG Aljustrel, um espólio científico fundamental para a investigação da Faixa Piritosa Ibérica e da Zona de Ossa-MorenaPublication . Matos, João Xavier; Morais, Igor; Santos, Sara; Gonçalves, Pedro; Batista, Maria Joao; de Oliveira, Daniel Pipa Soares; Dias, Ruben PereiraSUMMARY: Since 2018 the LNEG’s Aljustrel drill core shed is dedicated to the southern Portugal collections distributed by Iberian Pyrite Belt (IPB) and Ossa-Morena Zone (OMZ). The archive includes exploration drill hole cores, soil, stream sediments and rock samples, technical reports, and a complete and detail map collection (1/5.000 and 1/25.000 scales), all organized in databases. Drill hole relog allow a better understanding of the subsurface being essential in stratigraphy, structural mapping, mineral exploration and metallogeny. Following the regional Smart Specialization Strategy defined by CCDR Alentejo to Geological Resources, the LNEG Aljustrel develops R&D programs dedicated to thematic mapping and mineral resources. Critical Raw Materials mineralizations are present at the archives like IPB VMS Cu-Zn-Pb(Au-Ag-Sn-Sb) and Fe-Mn deposits and OMZ sulphide-magnetite (Zn-Pb,Cu(Au)), magnetite and Cu(Au) veins. The preservation of the subsurface geological heritage is critical to the IPB and OMZ research and an institutional LNEG mission.
- Valorização de recursos minerais : contribuição do projecto MinReMol para uma recuperação sustentável do rénio a partir de resíduos mineirosPublication . Silva, Teresa; Figueiredo, M. Ondina; Santos, Renata; de Oliveira, Daniel Pipa Soares; Veiga, JP; Batista, Maria Joao
- Contribution to the Understanding of the Colour Change in Bluish-Grey LimestonesPublication . Silva, Teresa; De Oliveira, Daniel Pipa Soares; Veiga, JP; Lisboa, Jose; Carvalho, Jorge; Barreiros, M. Alexandra; Coutinho, ML; Salas-Colera, Eduardo; Vigário, RogérioABSTRACT: Bluish-grey limestones have been extensively used as ornamental stones for decoration purposes in buildings, as well as in works of art, and accordingly, have been the target of intense exploration. In Portugal, the Jurassic limestone massif known as the Macico Calcario Estremenho (MCE), has been the source of grey-coloured ornamental stones, namely the Azul Valverde (one of the most well-known bluish-grey limestones) and Atlantic Blue varieties, both of which may undergo colour changes in outdoor environments. In this sense, it is important to understand the sudden colour change from bluish-grey to yellow/beige in the same limestone block in a quarry, or even, what happens to the colour when polished limestone is placed outdoors. This study was undertaken using various techniques, namely XRF (X-ray fluorescence spectrometry), XRD (X-ray diffraction), SEM (scanning electron microscopy), DTA-TG (differential thermal analysis/thermogravimetry) and colourimetry. Synchrotron radiation was also used at the European Synchrotron Radiation Facility (ESRF, Grenoble, France) where XANES (X-ray Absorption Near Edge Structure) spectra at Fe K-edge were collected to ascertain the speciation state of Fe in different coloured zones of the limestone, previously checked by EDXRF (energy dispersive X-ray fluorescence). The presence of Fe2+ and Fe3+ are responsible for the greyish and yellow/brown colour, respectively. On the other hand, the UV radiation from the sun causes a quickened and severe bleaching/fading on the dark blue/grey polished limestone.
- Late-stage gold (Electrum) in the Lousal Mine, Iberian Pyrite Belt, PortugalPublication . de Oliveira, Daniel Pipa Soares; Rosa, Carlos J. P.; Guimarães, Fernanda; Matos, João Xavier; Rosa, Diogo; Pereira, Zélia; Frias, Vasco C. S.
- Pan-European geological data, information, and knowledge for a resilient, sustainable, and collaborative futurePublication . Hollis, Julie; Bricker, Stephanie; Čápová, Dana; Hinsby, Klaus; Krenmayr, Hans-Georg; Negrel, Phillippe; de Oliveira, Daniel Pipa Soares; Poyiadji, Eleftheria; van Gessel, Serge; van Heteren, Sytze; Venvik, GuriABSTRACT: Many fields of research relevant to climate-change-related policy are grounded in geological sciences – far more than is generally recognised by the public or policy makers. These fields include management of marine environments, urban development, groundwater, landslide risk, understanding the geochemistry of soils and water, and securing raw materials. Through the concerted collaborative efforts, over many years, of EuroGeoSurveys – the Geological Surveys of Europe – national datasets bearing on these and other areas have been harmonised at European scale and delivered through an online digital platform, the European Geological Data Infrastructure. This vast store of baseline data, information, and knowledge is crucial for informed pan-European decision making and is considered the core of a future Geological Service for Europe.
- Towards the recovery of by-product metals from mine wastes : an X-Ray absorption spectroscopy study on the binding state of rhenium in debris from a centennial Iberian Pyrite Belt minePublication . Figueiredo, M. Ondina; Silva, Teresa; Veiga, JP; de Oliveira, Daniel Pipa Soares; Batista, Maria JoaoRhenium is a very scarce element, occurring in the Earth's crust mainly carried by molybdenite (MoS2). Due to a very low availability comparative to actual industrial demand, rhenium is nowadays one of the most expensive mineral commodities and an increased interest is focused on exploring residues resulting from a long-term mining, particularly of sulphide ore deposits. It is therefore noteworthy to assign the presence of rhenium (in a concentration up to 3 ppm) in the waste materials from the old sulphur factory at the abandoned mine of São Domingos (Iberian Pyrite Belt, Southeast Portugal), exploited since the Roman occupation of Iberia. Aiming at a potential sustainable recovery of rhenium as a by-product, X-ray near-edge absorption spectroscopy (XANES) was applied to clarify the Re-binding and mode of occurrence by comparing Re L3-edge XANES spectra obtained from mine waste samples (previously fully characterized by X-ray laboratory techniques) with similar spectra collected from Re-rich molybdenites (Mo1-xRexS2) and from Re-O model compounds configuring various valences and coordination environments of rhenium ions. Obtained results are commented, ruling out a possible Re-S binding and rather conforming with the binding of rhenium to oxygen in the analysed mine waste materials.
- Dados Copernicus na caracterização e monitorização de recursos geológicos em Portugal [Resumo]Publication . Quental, Lídia; Gonçalves, Pedro; de Oliveira, Daniel Pipa Soares; Patinha, Pedro; Dias, Ruben Pereira
- Mineral prospectivity mapping for critical raw materials at the European scale with the CBA method [Resumo]Publication . Bertrand, Guillaume; Sadeghi, Martiya; De Oliveira, Daniel Pipa Soares; Tourlière, B.; Arvanitidis, Nikolaos; Gautneb, Håvard; Gloaguen, Eric; Törmänen, Tuomo; Reginiussen, Helge; Decree, Sophie; Pereira, Aurete; Quental, LídiaABSTRACT: This contribution presents pan-European prospectivity maps for lithium, cobalt, natural graphite, niobium, tantalum, phosphates and rare earth elements that were produced by the GeoERA FRAME project. These maps are based on the cell-based association (CBA) method, which was specifically developed for mineral prospectivity mapping at regional to continental scales. The purpose of this method is to address issues such as uncertainties in the location of cartographic objects and the need to consider geological contexts. Several options to calculate favourability scores were statistically tested and compared to improve the accuracy of the method and produce the final maps.
- Testing the use of FDEM EM34 for disseminated chromite prospecting in Trás-os-Montes, PortugalPublication . Ramalho, Elsa; de Oliveira, Daniel Pipa Soares; Santana, Helena
- Uma abordagem de sensores multi-escala para áreas mineiras no sul de Portugal: do satélite ao sUASA [Resumo]Publication . Gonçalves, Pedro; Quental, Lídia; Patinha, Pedro; de Oliveira, Daniel Pipa SoaresRESUMO: A deteção remota com recurso a satélites e sUAS fornecem informações cruciais, particularmente em geologia, permitindo a discriminação de unidades litológicas, características estruturais e ocorrências minerais. As imagens de alta resolução espectral, espacial e temporal permitem uma análise mais detalhada e apoiam na identificação de zonas de alteração que podem indicar ocorrências minerais e gerar dados valiosos nas várias fases do ciclo de vida da mina.