Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal)
Autor(a) principal: | |
---|---|
Data de Publicação: | 2019 |
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/10174/27476 |
Resumo: | The Monges deposit was an important iron mine during late 19th and early 20th century. In recent decades the region of Montemor-o-Novo has attracted the interest of several exploration companies due to high-grade gold anomalies found through soil geochemistry work. Exploration drilling carried out in the WNW-ESE and conjugated N-S shear-zones (≈30 km) identified interesting gold grades, including in the vicinity of the Monges iron deposit. The fluid inclusion study presented here is focused on constraining the fluids related to iron and gold mineralization processes. Fluid constraints for the iron mineralization are difficult assess in the early stage (SEDEX environment) of the Ossa-Morena Zone geodynamic evolution. An overprinting of these early fluids is found, and most of the fluids present may be related to late metamorphism. Gold in Monges area shows affinity to a H2O-CO2-NaCl fluid system showing evidence of immiscibility and trace concentrations of CH4. The geological settings hosting gold mineralization as well as the fluid characteristics with low-salinity, with an average of 7.72 wt. % NaCl Equiv. and homogenization temperatures between 150ºC and 350ºC, points towards an orogenic gold deposit model, corroborating and reinforcing the current accepted model for gold mineralization of Montemor-o-Novo region. |
id |
RCAP_85ccde4d022e97f2bd82366f0415bc81 |
---|---|
oai_identifier_str |
oai:dspace.uevora.pt:10174/27476 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal)Zona de Ossa-MorenaInclusões FluidasMina dos MongesOuroThe Monges deposit was an important iron mine during late 19th and early 20th century. In recent decades the region of Montemor-o-Novo has attracted the interest of several exploration companies due to high-grade gold anomalies found through soil geochemistry work. Exploration drilling carried out in the WNW-ESE and conjugated N-S shear-zones (≈30 km) identified interesting gold grades, including in the vicinity of the Monges iron deposit. The fluid inclusion study presented here is focused on constraining the fluids related to iron and gold mineralization processes. Fluid constraints for the iron mineralization are difficult assess in the early stage (SEDEX environment) of the Ossa-Morena Zone geodynamic evolution. An overprinting of these early fluids is found, and most of the fluids present may be related to late metamorphism. Gold in Monges area shows affinity to a H2O-CO2-NaCl fluid system showing evidence of immiscibility and trace concentrations of CH4. The geological settings hosting gold mineralization as well as the fluid characteristics with low-salinity, with an average of 7.72 wt. % NaCl Equiv. and homogenization temperatures between 150ºC and 350ºC, points towards an orogenic gold deposit model, corroborating and reinforcing the current accepted model for gold mineralization of Montemor-o-Novo region.Proceedings of the 15th SGA Biennal Meeting, 27-30 August 2019, Glasgow, Scotland2020-02-28T10:38:53Z2020-02-282019-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10174/27476http://hdl.handle.net/10174/27476engMAIA M., SÃO PEDRO D., MIRÃO J., NORONHA F., NOGUEIRA P. (2019). Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal). Proceedings of the 15th SGA Biennal Meeting, 27-30 August 2019, Glasgow, Scotland, pages 252-255. ISBN: 978-0-85261-962-9mcmaiageo@gmail.comdiogo_rm_sp@hotmail.comjmirao@uevora.ptfmnoronh@fc.up.ptpmn@uevora.pt250MAIA, MiguelSÃO PEDRO, DiogoMIRÃO, JoséNORONHA, FernandoNOGUEIRA, Pedroinfo: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:RCAAP2024-01-03T19:22:57Zoai:dspace.uevora.pt:10174/27476Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T01:17:32.345081Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) |
title |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) |
spellingShingle |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) MAIA, Miguel Zona de Ossa-Morena Inclusões Fluidas Mina dos Monges Ouro |
title_short |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) |
title_full |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) |
title_fullStr |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) |
title_full_unstemmed |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) |
title_sort |
Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal) |
author |
MAIA, Miguel |
author_facet |
MAIA, Miguel SÃO PEDRO, Diogo MIRÃO, José NORONHA, Fernando NOGUEIRA, Pedro |
author_role |
author |
author2 |
SÃO PEDRO, Diogo MIRÃO, José NORONHA, Fernando NOGUEIRA, Pedro |
author2_role |
author author author author |
dc.contributor.author.fl_str_mv |
MAIA, Miguel SÃO PEDRO, Diogo MIRÃO, José NORONHA, Fernando NOGUEIRA, Pedro |
dc.subject.por.fl_str_mv |
Zona de Ossa-Morena Inclusões Fluidas Mina dos Monges Ouro |
topic |
Zona de Ossa-Morena Inclusões Fluidas Mina dos Monges Ouro |
description |
The Monges deposit was an important iron mine during late 19th and early 20th century. In recent decades the region of Montemor-o-Novo has attracted the interest of several exploration companies due to high-grade gold anomalies found through soil geochemistry work. Exploration drilling carried out in the WNW-ESE and conjugated N-S shear-zones (≈30 km) identified interesting gold grades, including in the vicinity of the Monges iron deposit. The fluid inclusion study presented here is focused on constraining the fluids related to iron and gold mineralization processes. Fluid constraints for the iron mineralization are difficult assess in the early stage (SEDEX environment) of the Ossa-Morena Zone geodynamic evolution. An overprinting of these early fluids is found, and most of the fluids present may be related to late metamorphism. Gold in Monges area shows affinity to a H2O-CO2-NaCl fluid system showing evidence of immiscibility and trace concentrations of CH4. The geological settings hosting gold mineralization as well as the fluid characteristics with low-salinity, with an average of 7.72 wt. % NaCl Equiv. and homogenization temperatures between 150ºC and 350ºC, points towards an orogenic gold deposit model, corroborating and reinforcing the current accepted model for gold mineralization of Montemor-o-Novo region. |
publishDate |
2019 |
dc.date.none.fl_str_mv |
2019-01-01T00:00:00Z 2020-02-28T10:38:53Z 2020-02-28 |
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/10174/27476 http://hdl.handle.net/10174/27476 |
url |
http://hdl.handle.net/10174/27476 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
MAIA M., SÃO PEDRO D., MIRÃO J., NORONHA F., NOGUEIRA P. (2019). Fluid constraints for Au deposition at the Monges iron deposit, Ossa Morena Zone (Montemor-o-Novo, Portugal). Proceedings of the 15th SGA Biennal Meeting, 27-30 August 2019, Glasgow, Scotland, pages 252-255. ISBN: 978-0-85261-962-9 mcmaiageo@gmail.com diogo_rm_sp@hotmail.com jmirao@uevora.pt fmnoronh@fc.up.pt pmn@uevora.pt 250 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Proceedings of the 15th SGA Biennal Meeting, 27-30 August 2019, Glasgow, Scotland |
publisher.none.fl_str_mv |
Proceedings of the 15th SGA Biennal Meeting, 27-30 August 2019, Glasgow, Scotland |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799136657701601280 |