The Iberian Pyrite Belt (IPB) is a volcanic- and shale-hosted massive sulfides world-class province of the Upper Paleozoic age that includes some supergiant ore deposits with a unique mining operations history. An extensive soil (multi-element) geochemical survey in the IPB has been performed to create a geochemical database to increase the knowledge of the studied area. Both univariate and multivariate treatments have been done to manage a large amount of new data. The studied area shows higher background concentrations of several elements (e.b. Cu, Pb, Zn, Cd, Sn, In, Bi, As, or Sb) than in other terrains in Spain due to the IPB volcano-sedimentary ore deposits and their associated mining wastes. Mapping chemical elements help understand their behavior, controls and associations in natural environments. According to this, the mono-elemental contour maps show single-element distributions with geological control (e.g., Na), ore deposit control (e.g., Cu) or a mixture of both. On the other hand, multivariate analysis has been applied to reduce the large geochemical database maintaining the same information. We have chosen Factorial Analysis (FA) and obtained six factors that explain approximately 70% of the variability. Four of these factors (F1, F2, F4 and F5) show an intense geological control that improves the geological information of the IPB, while the other two (F3 and F5) show an ore deposit control. These factors allow distinguishing between different types of deposits in the IPB and help discover new possible exploration targets for future studies.

The Iberian Pyrite Belt (IPB) is a metallogenic province in SW Spain and Portugal hosting the largest concentration of massive sulfide deposits worldwide. Exploration campaigns in both the Spanish and Portuguese sectors of the IPB have increased recently due to the rise in metal prices. Within this framework, distinguishing geochemical features associated with natural phenomena and isolating geogenic anomalies from anthropogenic ones can pose a challenge. This contribution uses the residual soil geochemical database of the IPB (Spain) to examine numerous variables, encompassing major, minor and trace elements. Some of these variables commonly exhibit high correlations owing to consistent geochemical behaviour. However, the influence of anthropogenic factors tends to elevate data variability, occasionally masking the natural relationships that govern their distributions. We apply different treatments of data to develop factor analysis using log-transformed data, and centred log-ratio (clr) transformed data to compare and improve the geochemical interpretation of this important zone. Factor analysis has been developed with these results to compare with previously published research on factor analysis in raw data. Factor score interpolated maps were also generated using both lognormal and clr-transformed data to visualize better the distribution and the different geochemical associations in the IPB. This study shows the importance of the different data treatments and the improvement of the clr-transformed multivariate analysis to reduce the dilution or overestimation of the results of some elements that cause erroneous interpretations of the data.

A major geochemical exploration campaign was carried out in SW Angola during the PLANAGEO project, including the analysis of rock, soil, and stream sediment samples using in situ portable X-ray fluorescence (pXRF) analysers. The present work focuses on the analytical results obtained in the area of the Giraúl Pegmatitic Field, a world-class Li-rich pegmatitic dike swarm, as well as on adjacent areas with potential for critical element mineralisation. In situ pXFR geochemical analyses revealed high Nb and Ta contents in the pegmatites of Giraúl, in the surrounding soils, suggesting a clear relation to LCT pegmatites. The most important Nb contents are found in denudated soils from the Cretaceous latite volcanic units of the Bero Volcanic Complex, reaching values up to 896 mg/kg. This work has enabled to define some areas of special interest: (a) the Giraúl Pegmatitic Field, where significant anomalous concentrations of Nb-Ta (Li-Be) occur; (b) the amphibolitic units of the Namibe Group metasediments and other mafic Palaeoproterozoic intrusions, which show potential interest for base metal (Cr-Ni-Co, Cu) exploration; and (c) the Cretaceous volcanic rocks of the Namibe Basin, in the coastal region, which hold potential interest for Fe-Ti (V).

El Plan Nacional de Geología de Angola (PLANAGEO) fue uno de los proyectos de infraestructura angolanos más importantes de los últimos 20 años. Sus principales objetivos fueron: a) mejorar el conocimiento de los recursos geológico-mineros de Angola; b) fomentar la diversificación de la economía nacional; y, c) atraer inversión extranjera y promover el desarrollo del país. El proyecto integró estudios regionales geológicos, aerogeofísicos y geoquímicos; y prospección de materias primas y recursos minerales en áreas objetivo. El proyecto fue publicado por el gobierno angoleño (Resolución Presidencial 52/09) e implementado por el Servicio Geológico de Angola (IGEO), bajo la supervisión del Ministerio de Recursos Minerales, Petróleo y Gas de Angola (MIREMPET). En 2011, el consorcio UTE, formado por el IGME, el Laboratorio Nacional de Energía y Geología de Portugal (LNEG) y la empresa Impulso Industrial Alternativo (IIA) concurrió a su licitación internacional. Finalmente, IGEO adjudicó a la UTE el contrato para ejecutar PLANAGEO en la región suroeste de Angola, cubriendo aproximadamente 480.000 km2, que se firmó en octubre de 2013. Entre julio de 2014 y finales de 2022, la UTE realizó estudios e investigaciones interdisciplinarias que resultaron en una colección integral de mapas, informes y documentos científicos, que comprende las siguientes cartografías: Geofísica aérea magnética/radiométrica. Geológica a escala 1:250.000 (con síntesis 1:500.000 y 1:1.000.000), y 1:100.000 en áreas seleccionadas. Geoquímica a escala 1:250.000. Mapeo de materias primas y recursos minerales en áreas de interés a escala 1:50.000