Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits
Autor(a) principal: | |
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Data de Publicação: | 2022 |
Outros Autores: | , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10174/32582 https://doi.org/Gaspar, M.; Grácio, N.; Salgueiro, R.; Costa, M. Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits. Minerals 2022, 12, 1248. https://doi.org/10.3390/min12101248 https://doi.org/10.3390/min12101248 |
Resumo: | The Segura mining field, the easternmost segment of the Góis–Panasqueira–Segura tin– tungsten metallogenic belt (north–central Portugal), includes Sn-W quartz veins and Li-Sn aplitepegmatites, which are believed to be genetically related to Variscan Granites. Sediment geochemistry indicates granite-related Ti-enrichments, locally disturbed by mineralization, suggesting magmatic and metamorphic/metasomatic titaniferous phases. Therefore, Segura alluvial samples and the geochemistry of their TiO2 polymorphs (rutile, anatase, and brookite) were investigated, and their potential as exploration tools for Sn and W deposits was evaluated. The heavy-mineral assemblages proved to be good proxies for bedrock geology, and TiO2 polymorph abundances were found to be suitable indicators of magmatic and/or metasomatic hydrothermal processes. The trace element geochemistry of Segura’s alluvial rutile, anatase, and brookite is highly variable, implying multiple sources and a diversity of mineral-forming processes. The main compositional differences between TiO2 polymorphs are related to intrinsic (structural) factors, and to the P-T-X extrinsic parameters of their forming environments. Anomalous enrichments, up to 9% Nb, 6% Sn andW, 3% Fe, 2% Ta, and 1% V in rutile, and up to 1.8% Fe, 1.7% Ta, 1.2% Nb, 1.1% W 0.5% Sn and V in anatase, were registered. Brookite usually has low trace element content (<0.5%), except for Fe (~1%). HFSE-rich and granitophile-rich rutile is most likely magmatic, forming in extremely differentiated melts, with Sn and W contents enabling the discrimination between Sn-dominant and W-dominant systems. Trace element geochemical distribution maps show pronounced negative Sn (rutile+anatase) and W (rutile) anomalies linked to hydrothermal cassiterite precipitation, as opposed to their hydrothermal alteration halos and toW-dominant cassiterite-free mineralized areas, where primary hydrothermal rutile shows enrichments similar to magmatic rutile. This contribution recognizes that trace element geochemistry of alluvial TiO2 polymorphs can be a robust, cost- and time-effective, exploration tool for Sn(W) and W(Sn) ore deposit systems. |
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Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W DepositsTiO2 polymorphsalluvialheavy mineralsSn-W depositstrace elementsgeochemical footprintsgeochemical fingerprintsgeochemical explorationThe Segura mining field, the easternmost segment of the Góis–Panasqueira–Segura tin– tungsten metallogenic belt (north–central Portugal), includes Sn-W quartz veins and Li-Sn aplitepegmatites, which are believed to be genetically related to Variscan Granites. Sediment geochemistry indicates granite-related Ti-enrichments, locally disturbed by mineralization, suggesting magmatic and metamorphic/metasomatic titaniferous phases. Therefore, Segura alluvial samples and the geochemistry of their TiO2 polymorphs (rutile, anatase, and brookite) were investigated, and their potential as exploration tools for Sn and W deposits was evaluated. The heavy-mineral assemblages proved to be good proxies for bedrock geology, and TiO2 polymorph abundances were found to be suitable indicators of magmatic and/or metasomatic hydrothermal processes. The trace element geochemistry of Segura’s alluvial rutile, anatase, and brookite is highly variable, implying multiple sources and a diversity of mineral-forming processes. The main compositional differences between TiO2 polymorphs are related to intrinsic (structural) factors, and to the P-T-X extrinsic parameters of their forming environments. Anomalous enrichments, up to 9% Nb, 6% Sn andW, 3% Fe, 2% Ta, and 1% V in rutile, and up to 1.8% Fe, 1.7% Ta, 1.2% Nb, 1.1% W 0.5% Sn and V in anatase, were registered. Brookite usually has low trace element content (<0.5%), except for Fe (~1%). HFSE-rich and granitophile-rich rutile is most likely magmatic, forming in extremely differentiated melts, with Sn and W contents enabling the discrimination between Sn-dominant and W-dominant systems. Trace element geochemical distribution maps show pronounced negative Sn (rutile+anatase) and W (rutile) anomalies linked to hydrothermal cassiterite precipitation, as opposed to their hydrothermal alteration halos and toW-dominant cassiterite-free mineralized areas, where primary hydrothermal rutile shows enrichments similar to magmatic rutile. This contribution recognizes that trace element geochemistry of alluvial TiO2 polymorphs can be a robust, cost- and time-effective, exploration tool for Sn(W) and W(Sn) ore deposit systems.MDPI2022-10-18T10:44:11Z2022-10-182022-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10174/32582https://doi.org/Gaspar, M.; Grácio, N.; Salgueiro, R.; Costa, M. Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits. Minerals 2022, 12, 1248. https://doi.org/10.3390/min12101248http://hdl.handle.net/10174/32582https://doi.org/10.3390/min12101248enghttps://www.mdpi.com/2075-163X/12/10/1248ndndndmcosta@uevora.ptGaspar, MiguelGrácio, NunoSalgueiro, RuteCosta, Mafaldainfo:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2023-08-08T04:47:20ZPortal AgregadorONG |
dc.title.none.fl_str_mv |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits |
title |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits |
spellingShingle |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits Gaspar, Miguel TiO2 polymorphs alluvial heavy minerals Sn-W deposits trace elements geochemical footprints geochemical fingerprints geochemical exploration |
title_short |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits |
title_full |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits |
title_fullStr |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits |
title_full_unstemmed |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits |
title_sort |
Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits |
author |
Gaspar, Miguel |
author_facet |
Gaspar, Miguel Grácio, Nuno Salgueiro, Rute Costa, Mafalda |
author_role |
author |
author2 |
Grácio, Nuno Salgueiro, Rute Costa, Mafalda |
author2_role |
author author author |
dc.contributor.author.fl_str_mv |
Gaspar, Miguel Grácio, Nuno Salgueiro, Rute Costa, Mafalda |
dc.subject.por.fl_str_mv |
TiO2 polymorphs alluvial heavy minerals Sn-W deposits trace elements geochemical footprints geochemical fingerprints geochemical exploration |
topic |
TiO2 polymorphs alluvial heavy minerals Sn-W deposits trace elements geochemical footprints geochemical fingerprints geochemical exploration |
description |
The Segura mining field, the easternmost segment of the Góis–Panasqueira–Segura tin– tungsten metallogenic belt (north–central Portugal), includes Sn-W quartz veins and Li-Sn aplitepegmatites, which are believed to be genetically related to Variscan Granites. Sediment geochemistry indicates granite-related Ti-enrichments, locally disturbed by mineralization, suggesting magmatic and metamorphic/metasomatic titaniferous phases. Therefore, Segura alluvial samples and the geochemistry of their TiO2 polymorphs (rutile, anatase, and brookite) were investigated, and their potential as exploration tools for Sn and W deposits was evaluated. The heavy-mineral assemblages proved to be good proxies for bedrock geology, and TiO2 polymorph abundances were found to be suitable indicators of magmatic and/or metasomatic hydrothermal processes. The trace element geochemistry of Segura’s alluvial rutile, anatase, and brookite is highly variable, implying multiple sources and a diversity of mineral-forming processes. The main compositional differences between TiO2 polymorphs are related to intrinsic (structural) factors, and to the P-T-X extrinsic parameters of their forming environments. Anomalous enrichments, up to 9% Nb, 6% Sn andW, 3% Fe, 2% Ta, and 1% V in rutile, and up to 1.8% Fe, 1.7% Ta, 1.2% Nb, 1.1% W 0.5% Sn and V in anatase, were registered. Brookite usually has low trace element content (<0.5%), except for Fe (~1%). HFSE-rich and granitophile-rich rutile is most likely magmatic, forming in extremely differentiated melts, with Sn and W contents enabling the discrimination between Sn-dominant and W-dominant systems. Trace element geochemical distribution maps show pronounced negative Sn (rutile+anatase) and W (rutile) anomalies linked to hydrothermal cassiterite precipitation, as opposed to their hydrothermal alteration halos and toW-dominant cassiterite-free mineralized areas, where primary hydrothermal rutile shows enrichments similar to magmatic rutile. This contribution recognizes that trace element geochemistry of alluvial TiO2 polymorphs can be a robust, cost- and time-effective, exploration tool for Sn(W) and W(Sn) ore deposit systems. |
publishDate |
2022 |
dc.date.none.fl_str_mv |
2022-10-18T10:44:11Z 2022-10-18 2022-01-01T00:00:00Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10174/32582 https://doi.org/Gaspar, M.; Grácio, N.; Salgueiro, R.; Costa, M. Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits. Minerals 2022, 12, 1248. https://doi.org/10.3390/min12101248 http://hdl.handle.net/10174/32582 https://doi.org/10.3390/min12101248 |
url |
http://hdl.handle.net/10174/32582 https://doi.org/Gaspar, M.; Grácio, N.; Salgueiro, R.; Costa, M. Trace Element Geochemistry of Alluvial TiO2 Polymorphs as a Proxy for Sn and W Deposits. Minerals 2022, 12, 1248. https://doi.org/10.3390/min12101248 https://doi.org/10.3390/min12101248 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
https://www.mdpi.com/2075-163X/12/10/1248 nd nd nd mcosta@uevora.pt |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
MDPI |
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MDPI |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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