The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola
The Giraúl granitic pegmatite field in Angola is composed of five pegmatite types, the most evolved belong to the beryl-columbite, beryl-columbite-phosphate and spodumene types. Pegmatites are concentrically zoned with increased grain size toward a quartz core; the most evolved pegmatites have well-...
| Autores: | ; ; ; ; ; ; ; |
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| Tipo de documento: | Artículo |
| Estado: | Published version |
| Fecha de publicación: | 2019 |
| País: | España |
| Institución: | Universidad de Barcelona |
| Repositorio: | Dipòsit Digital de la UB |
| OAI Identifier: | oai:diposit.ub.edu:2445/158762 |
| Acceso en línea: | https://hdl.handle.net/2445/158762 |
| Nivel de acceso: | Acceso abierto |
| Palabra clave: | Pegmatites Minerals Cendres volcàniques Angola Volcanic ash |
| _version_ | 1878729541305761793 |
|---|---|
| author | Gonçalves, Antonio Olimpio |
| author2 | Melgarejo i Draper, Joan-Carles Alfonso Abella, María Pura Amores Casals, Sandra Paniagua, Andrés Neto, André Buta Alves Morais, Eduardo Camprubí, Antoni |
| author2_role | author author author author author author author |
| author_browse | Alfonso Abella, María Pura Alves Morais, Eduardo Amores Casals, Sandra Camprubí, Antoni Gonçalves, Antonio Olimpio Melgarejo i Draper, Joan-Carles Neto, André Buta Paniagua, Andrés |
| author_facet | Gonçalves, Antonio Olimpio Melgarejo i Draper, Joan-Carles Alfonso Abella, María Pura Amores Casals, Sandra Paniagua, Andrés Neto, André Buta Alves Morais, Eduardo Camprubí, Antoni |
| author_role | author |
| collection | Dipòsit Digital de la UB |
| description | The Giraúl granitic pegmatite field in Angola is composed of five pegmatite types, the most evolved belong to the beryl-columbite, beryl-columbite-phosphate and spodumene types. Pegmatites are concentrically zoned with increased grain size toward a quartz core; the most evolved pegmatites have well-developed replacement units. These pegmatites are rich in Nb-Ta oxide minerals and the field has a moderate interest for critical elements such as Ta and Hf. Tourmaline, garnet and micas occur as accessory minerals. The abundance of Zr and Nb-Ta minerals increases with the evolution of the pegmatites, as well as the proportions of beryl and Li-rich minerals. The Ta/(Ta + Nb) ratio in Nb-Ta oxide minerals and the Hf/(Hf + Zr) ratio in zircon also increase with the evolution of the pegmatites and within each pegmatite body from border to inner zones, and especially in the late veins and subsolidus replacements. Textural patterns and occurrence of late veins with Ta-rich minerals suggest that Nb and especially Ta can be enriched in late hydrothermal fluids exsolved from the magma, along with Hf and other incompatible elements as Sn, U, Pb, Sb and Bi. |
| eu_rights_str_mv | openAccess |
| format | article |
| id | ES_09fc8dfd4fe60dd6ed5e9d4065d0682a |
| institution | Universidad de Barcelona |
| instname_str | Universidad de Barcelona |
| network_acronym_str | ES |
| network_name_str | España |
| oai_identifier_str | oai:diposit.ub.edu:2445/158762 |
| publishDate | 2019 |
| publishDateSort | 2019 |
| publisher | MDPI |
| publisherStr | MDPI |
| reponame_str | Dipòsit Digital de la UB |
| spelling | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola Gonçalves, Antonio Olimpio Melgarejo i Draper, Joan-Carles Alfonso Abella, María Pura Amores Casals, Sandra Paniagua, Andrés Neto, André Buta Alves Morais, Eduardo Camprubí, Antoni Pegmatites Minerals Cendres volcàniques Angola Volcanic ash The Giraúl granitic pegmatite field in Angola is composed of five pegmatite types, the most evolved belong to the beryl-columbite, beryl-columbite-phosphate and spodumene types. Pegmatites are concentrically zoned with increased grain size toward a quartz core; the most evolved pegmatites have well-developed replacement units. These pegmatites are rich in Nb-Ta oxide minerals and the field has a moderate interest for critical elements such as Ta and Hf. Tourmaline, garnet and micas occur as accessory minerals. The abundance of Zr and Nb-Ta minerals increases with the evolution of the pegmatites, as well as the proportions of beryl and Li-rich minerals. The Ta/(Ta + Nb) ratio in Nb-Ta oxide minerals and the Hf/(Hf + Zr) ratio in zircon also increase with the evolution of the pegmatites and within each pegmatite body from border to inner zones, and especially in the late veins and subsolidus replacements. Textural patterns and occurrence of late veins with Ta-rich minerals suggest that Nb and especially Ta can be enriched in late hydrothermal fluids exsolved from the magma, along with Hf and other incompatible elements as Sn, U, Pb, Sb and Bi. MDPI https://hdl.handle.net/2445/158762 |
| spellingShingle | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola Gonçalves, Antonio Olimpio Pegmatites Minerals Cendres volcàniques Angola Volcanic ash |
| status_str | publishedVersion |
| title | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola |
| title_full | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola |
| title_fullStr | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola |
| title_full_unstemmed | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola |
| title_short | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola |
| title_sort | The distribution of rare metals in the LCT pegmatites from the Giraúl Field, Angola |
| topic | Pegmatites Minerals Cendres volcàniques Angola Volcanic ash |
| topic_facet | Pegmatites Minerals Cendres volcàniques Angola Volcanic ash |
| url | https://hdl.handle.net/2445/158762 |