A LCT pegmatite spectral library of the aldeia spodumene deposit: contributes to mineral exploration

Several methodologies can be employed in the prospection of Lithium (Li) in hard-rock (pegmatites). Spectrometry analysis, a Remote Sensing (RS) technique, can be applied to understand the surface spectral response of a sample, both to identify the rock-forming or alteration minerals in its composition and to validate the data collected in situ (by sensors onboard satellites/drones, for example). This paper aims to make available for public use the information acquired on the spectral composition of rock samples from the Barroso pegmatite field in Portugal, within the scope of the INOVMINERAL4.0 project. As a result, a spectral library was created with 47 spectra, collected from 11 different samples. All data is made available in a universal format, thus contributing to open science, corroborating the validation of local spectral data, and stimulating the creation of other databases, in other locations.The authors acknowledge the support provided by Portuguese National Funds through the FCT – Fundação para a Ciência e a Tecnologia, I.P. (Portugal) projects UIDB/04683/2020 and UIDP/04683/2020 (Institute of Earth Sciences); through ANI and COMPETE 2020 as well as European funds through the European Regional Development Fund (ERDF) with POCI-01-0247-FEDER- 046083 INOVMINERAL project. The authors also thank Savannah Resources PLC for access to the Aldeia pegmatite and for providing the samples used in this study. Cátia Rodrigues de Almeida and Douglas Santos were financially supported by Portuguese national funds through FCT (Grant: PRT/BD/153518/2021, Grant: UI/BD/154412/2023, respectively).info:eu-repo/semantics/publishedVersio

The INOVMineral project’s contribution to mineral exploration - a WebGIS integration and visualization of spectral and geophysical properties of the aldeia lct pegmatite spodumene deposit

Due to the current energetic transition, new geological exploration technologies are needed to discover mineral deposits containing critical materials such as lithium (Li). The vast majority of European Li deposits are related to Li–Cs–Ta (LCT) pegmatites. A review of the literature indicates that conventional exploration campaigns are dominated by geochemical surveys and related exploration tools. However, other exploration techniques must be evaluated, namely, remote sensing (RS) and geophysics. This work presents the results of the INOVMINERAL4.0 project obtained through alternative approaches to traditional geochemistry that were gathered and integrated into a webGIS application. The specific objectives were to: (i) assess the potential of high-resolution elevation data; (ii) evaluate geophysical methods, particularly radiometry; (iii) establish a methodology for spectral data acquisition and build a spectral library; (iv) compare obtained spectra with Landsat 9 data for pegmatite identification; and (v) implement a user-friendly webGIS platform for data integration and visualization. Radiometric data acquisition using geophysical techniques effectively discriminated pegmatites from host rocks. The developed spectral library provides valuable insights for spacebased exploration. Landsat 9 data accurately identified known LCT pegmatite targets compared with Landsat 8. The user-friendly webGIS platform facilitates data integration, visualization, and sharing, supporting potential users in similar exploration approaches.The authors acknowledge the support provided by Portuguese national funds through the FCT—Fundação para a Ciência e a Tecnologia, I.P. (Portugal) projects UIDB/04683/2020 and UIDP/04683/2020 (Institute of Earth Sciences), and through ANI and COMPETE 2020, as well as European funds through the European Regional Development Fund (ERDF) with the POCI- 01-0247-FEDER-046083 INOVMINERAL project. Douglas Santos was financially supported by Portuguese national funds through FCT (Grant: UI/BD/154412/2023). Ricardo Ribeiro is financially supported by FCT within the compass of his Ph.D. thesis, ref. SFRH/BD/140266/2018. C.R.d.A. was financially supported by Portuguese national funds through FCT (Grant: PRT/BD/153518/2021). The spectroradiometer equipment was purchased under the European Commission’s Horizon 2020 innovation programme under grant agreement no. 869274, project GREENPEG New Exploration Tools for European Pegmatite Green-Tech Resources.info:eu-repo/semantics/publishedVersio

Sedimentology of a distributive fluvial system: The Serra da Galga Formation, a new lithostratigraphic unit (Upper Cretaceous, Bauru Basin, Brazil)

The Bauru Basin of SE Brazil is a large (ca. 370,000 km2) Upper Cretaceous intracratonic feature, important for its fossil remains and of particular value as a source of regional palaeoclimatic information. Historically, lithostratigraphic reconstructions have been performed mainly for successions of the central and southern parts of the basin, resulting in a lithostratigraphic scheme that is not applicable to the northernmost regions. In particular, the northeastern deposits of the Marília Formation (Serra da Galga and Ponte Alta members) reveal lithological, stratigraphic, and palaeontological differences from southeastern and northwestern counterparts (Echaporã Member). Nevertheless, these deposits are considered as a single lithostratigraphic formation in the literature. To address this problem, this study demonstrates how the northeastern deposits of the Marília Formation do not show affinity to the rest of the unit. A more suitable lithostratigraphic model is proposed for the northeastern succession as a distinct and independent unit. Lithofacies and palaeopedological analysis, combined with lithostratigraphic mapping of the northeastern deposits, reveal 11 distinct lithofacies and three pedotypes over an area of ~450 km2. Sedimentary facies and pedotypes were assigned to six interbedded architectural elements: (a) type 1 channel fill, (b) type 2 channel fill, (c) type 3 channel fill, (d) interchannels, (e) palaeosols, and (f) calcrete beds. The succession is interpreted as a distributive fluvial system with overall direction of flow to the NNW, and which developed under the influence of a semiarid climate regime. This contrasts with deposits of the southeastern and northwestern Marília Formation, previously suggested to be of fine-grained aeolian affinity with interbedded poorly channelised deposits assigned to an aeolian sand sheet environment. By revising the existing lithostratigraphic scheme for the northeastern deposits, and contrasting them with laterally equivalent strata, this work demonstrates how the previously named Serra da Galga and Ponte Alta members reveal a unique set of lithological, architectural, and genetic signatures that permits to separate them from the Marília Formation. Finally, a new lithostratigraphic classification for the unit is proposed: the Serra da Galga Formation, whose deposition relates to an ancient distributive fluvial system.Fil: Soares, Marcus Vinícius Theodoro. Universidade Estadual de Campinas; BrasilFil: Basilici, Giorgio. Universidade Estadual de Campinas; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Universidad Nacional de Catamarca. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Secretaría de Industria y Minería. Servicio Geológico Minero Argentino. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja. - Provincia de La Rioja. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja; ArgentinaFil: da Silva Marinho, Thiago. Universidade Federal do Triângulo Mineiro; BrasilFil: Martinelli, Agustín Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Marconato, André. Universidade Federal de Ouro Preto; BrasilFil: Mountney, Nigel Philip. University Of Leeds.; Reino UnidoFil: Colombera, Luca. University Of Leeds.; Reino UnidoFil: Mesquita, Áquila Ferreira. Universidade Estadual de Campinas; BrasilFil: Vasques, Julia Tucker. Universidade Estadual de Campinas; BrasilFil: Junior, Francisco Romero Abrantes. Universidade Estadual de Campinas; BrasilFil: Ribeiro, Luiz Carlos Borges. Universidade Federal Do Triangulo Mineiro; Brasi