Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores
Main Author: | |
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Publication Date: | 2012 |
Other Authors: | , , , , , , , , |
Format: | Article |
Language: | eng |
Source: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Download full: | http://hdl.handle.net/10174/6755 https://doi.org/10.1007/s00410-012-0837-2 |
Summary: | The islands of the Azores archipelago emerge from an oceanic plateau built on lithosphere increasing in age with distance from the Mid-Atlantic Ridge from 10 to 45 Ma. Here, we present the first comprehensive major and trace element and Sr–Nd–Pb isotope data from Santa Maria, the easternmost island of the archipelago, along with published data from the other Azores islands situated much closer to the Mid-Atlantic Ridge axis. We can show that the distinctively more variable and more enriched trace element ratios at Santa Maria combined with a relatively small range in Sr–Nd–Pb isotope ratios are the result of low degrees of partial melting of a common Azores mantle plume source underneath thicker lithosphere. This implies that melt extraction processes and melting dynamics may be able to better preserve the trace element mantle source variability underneath thicker lithosphere. These conclusions may apply widely for oceanic melts erupted on relatively thick lithosphere. In addition, lower Ti/Sm and K/La ratios and SiO2 contents of Santa Maria lavas imply melting of a carbonated peridotite source. Mixing of variable portions of deep small-degree carbonated peridotite melts and shallow volatile-free garnet peridotite could explain the geochemical variability underneath Santa Maria in agreement with the volatile-rich nature of the Azores mantle source. However, Santa Maria is the Azores island where the CO2-rich nature of the mantle source is more evident, reflecting a combination of a smaller extent of partial melting and the positioning at the edge of the tilted Azores mantle plume. |
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Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, AzoresOcean Island BasaltsAzores Lithosphere thicknessMelting dynamicsCarbonated peridotiteThe islands of the Azores archipelago emerge from an oceanic plateau built on lithosphere increasing in age with distance from the Mid-Atlantic Ridge from 10 to 45 Ma. Here, we present the first comprehensive major and trace element and Sr–Nd–Pb isotope data from Santa Maria, the easternmost island of the archipelago, along with published data from the other Azores islands situated much closer to the Mid-Atlantic Ridge axis. We can show that the distinctively more variable and more enriched trace element ratios at Santa Maria combined with a relatively small range in Sr–Nd–Pb isotope ratios are the result of low degrees of partial melting of a common Azores mantle plume source underneath thicker lithosphere. This implies that melt extraction processes and melting dynamics may be able to better preserve the trace element mantle source variability underneath thicker lithosphere. These conclusions may apply widely for oceanic melts erupted on relatively thick lithosphere. In addition, lower Ti/Sm and K/La ratios and SiO2 contents of Santa Maria lavas imply melting of a carbonated peridotite source. Mixing of variable portions of deep small-degree carbonated peridotite melts and shallow volatile-free garnet peridotite could explain the geochemical variability underneath Santa Maria in agreement with the volatile-rich nature of the Azores mantle source. However, Santa Maria is the Azores island where the CO2-rich nature of the mantle source is more evident, reflecting a combination of a smaller extent of partial melting and the positioning at the edge of the tilted Azores mantle plume.Contributions to Mineralogy and Petrology2012-12-10T11:51:25Z2012-12-102012-12-04T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10174/6755http://hdl.handle.net/10174/6755https://doi.org/10.1007/s00410-012-0837-2engChristoph.Beier@fau.dejmata@fc.ul.ptndndndpedro@uevora.ptndsmmartins@fc.ul.ptndnd250Beier, ChristophMata, JoãoStöckhert, FerdinandMattielli, NadineBrandl, PhilippMadureira, PedroGenske, FelixMartins, SofiaMadeira, JoséHaase, Karsteninfo: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:RCAAP2024-01-03T18:46:23Zoai:dspace.uevora.pt:10174/6755Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-20T01:01:26.814654Repositório 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 |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores |
title |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores |
spellingShingle |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores Beier, Christoph Ocean Island Basalts Azores Lithosphere thickness Melting dynamics Carbonated peridotite |
title_short |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores |
title_full |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores |
title_fullStr |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores |
title_full_unstemmed |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores |
title_sort |
Geochemical evidence for melting of carbonated peridotite on Santa Maria Island, Azores |
author |
Beier, Christoph |
author_facet |
Beier, Christoph Mata, João Stöckhert, Ferdinand Mattielli, Nadine Brandl, Philipp Madureira, Pedro Genske, Felix Martins, Sofia Madeira, José Haase, Karsten |
author_role |
author |
author2 |
Mata, João Stöckhert, Ferdinand Mattielli, Nadine Brandl, Philipp Madureira, Pedro Genske, Felix Martins, Sofia Madeira, José Haase, Karsten |
author2_role |
author author author author author author author author author |
dc.contributor.author.fl_str_mv |
Beier, Christoph Mata, João Stöckhert, Ferdinand Mattielli, Nadine Brandl, Philipp Madureira, Pedro Genske, Felix Martins, Sofia Madeira, José Haase, Karsten |
dc.subject.por.fl_str_mv |
Ocean Island Basalts Azores Lithosphere thickness Melting dynamics Carbonated peridotite |
topic |
Ocean Island Basalts Azores Lithosphere thickness Melting dynamics Carbonated peridotite |
description |
The islands of the Azores archipelago emerge from an oceanic plateau built on lithosphere increasing in age with distance from the Mid-Atlantic Ridge from 10 to 45 Ma. Here, we present the first comprehensive major and trace element and Sr–Nd–Pb isotope data from Santa Maria, the easternmost island of the archipelago, along with published data from the other Azores islands situated much closer to the Mid-Atlantic Ridge axis. We can show that the distinctively more variable and more enriched trace element ratios at Santa Maria combined with a relatively small range in Sr–Nd–Pb isotope ratios are the result of low degrees of partial melting of a common Azores mantle plume source underneath thicker lithosphere. This implies that melt extraction processes and melting dynamics may be able to better preserve the trace element mantle source variability underneath thicker lithosphere. These conclusions may apply widely for oceanic melts erupted on relatively thick lithosphere. In addition, lower Ti/Sm and K/La ratios and SiO2 contents of Santa Maria lavas imply melting of a carbonated peridotite source. Mixing of variable portions of deep small-degree carbonated peridotite melts and shallow volatile-free garnet peridotite could explain the geochemical variability underneath Santa Maria in agreement with the volatile-rich nature of the Azores mantle source. However, Santa Maria is the Azores island where the CO2-rich nature of the mantle source is more evident, reflecting a combination of a smaller extent of partial melting and the positioning at the edge of the tilted Azores mantle plume. |
publishDate |
2012 |
dc.date.none.fl_str_mv |
2012-12-10T11:51:25Z 2012-12-10 2012-12-04T00:00:00Z |
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/10174/6755 http://hdl.handle.net/10174/6755 https://doi.org/10.1007/s00410-012-0837-2 |
url |
http://hdl.handle.net/10174/6755 https://doi.org/10.1007/s00410-012-0837-2 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Christoph.Beier@fau.de jmata@fc.ul.pt nd nd nd pedro@uevora.pt nd smmartins@fc.ul.pt nd nd 250 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Contributions to Mineralogy and Petrology |
publisher.none.fl_str_mv |
Contributions to Mineralogy and Petrology |
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 |
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1799136497435148288 |