Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland
Autor(a) principal: | |
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Data de Publicação: | 2021 |
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/10451/50562 |
Resumo: | The aim of this work is to study the process of transformation of debris-free mountain glaciers into debris-covered glaciers and rock glaciers, and to examine the factors driving diverging evolution in similar glacial systems. The study area is the Hofsdalur valley, in the Tröllaskagi peninsula (northern Iceland), where several cirques host a great diversity of glaciers and rock glaciers as well as various glacial landforms. Four adjacent cirques have been analysed through a multidisciplinary approach: geomorphological analysis, boulder surface displacement tracking, quantification of recent glacier changes, three dimensional palaeoglacier reconstruction, equilibrium-line altitude calculations and relative and direct dating methods applied to surface boulders. Dating methods included in situ 36Cl cosmic-ray exposure dating, Schmidt hammer weathering measurements and lichenometric dating. The results confirm that glaciers in Hofsdalur followed an evolution pattern similar to that observed in other cirques in the Tröllaskagi peninsula. During the Younger Dryas (12.9–11.7 ka) many of those cirques hosted debris-free glaciers, whose retreat started in the early Holocene. Distinct retreat dynamics and cirque floor elevation conditioned the subsequent glacial evolution. In some Tröllaskagi cirques, the ice completely covered the headwalls, which consequently did not supply debris onto the glacier surface, which remained debris-free. In most of these cirques, however, glacier retreat enhanced paraglacial processes and the ice-free cirque walls generated a high debris supply onto the glacier surface. As a result, the glaciers evolved towards debris-covered glaciers or rock glaciers, depending on the local topographical setting. In the lower cirques they collapsed immediately after their formation. At higher altitudes, above the lower permafrost limit, these ice-cored landforms have survived until the present day, but they have been stagnant since the Holocene Thermal Maximum, while the heads of these cirques have hosted debris-free glaciers during the Late Holocene. |
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Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern IcelandIcelandHofsdalurTröllaskagi peninsulaGlacial evolutionDebris-covered glaciersRock glaciersYounger dryasHoloceneHolocene thermal maximumThe aim of this work is to study the process of transformation of debris-free mountain glaciers into debris-covered glaciers and rock glaciers, and to examine the factors driving diverging evolution in similar glacial systems. The study area is the Hofsdalur valley, in the Tröllaskagi peninsula (northern Iceland), where several cirques host a great diversity of glaciers and rock glaciers as well as various glacial landforms. Four adjacent cirques have been analysed through a multidisciplinary approach: geomorphological analysis, boulder surface displacement tracking, quantification of recent glacier changes, three dimensional palaeoglacier reconstruction, equilibrium-line altitude calculations and relative and direct dating methods applied to surface boulders. Dating methods included in situ 36Cl cosmic-ray exposure dating, Schmidt hammer weathering measurements and lichenometric dating. The results confirm that glaciers in Hofsdalur followed an evolution pattern similar to that observed in other cirques in the Tröllaskagi peninsula. During the Younger Dryas (12.9–11.7 ka) many of those cirques hosted debris-free glaciers, whose retreat started in the early Holocene. Distinct retreat dynamics and cirque floor elevation conditioned the subsequent glacial evolution. In some Tröllaskagi cirques, the ice completely covered the headwalls, which consequently did not supply debris onto the glacier surface, which remained debris-free. In most of these cirques, however, glacier retreat enhanced paraglacial processes and the ice-free cirque walls generated a high debris supply onto the glacier surface. As a result, the glaciers evolved towards debris-covered glaciers or rock glaciers, depending on the local topographical setting. In the lower cirques they collapsed immediately after their formation. At higher altitudes, above the lower permafrost limit, these ice-cored landforms have survived until the present day, but they have been stagnant since the Holocene Thermal Maximum, while the heads of these cirques have hosted debris-free glaciers during the Late Holocene.ElsevierRepositório da Universidade de LisboaTanarro, Luis M.Palacios, DavidFernández-Fernández, Jose M.Andrés, NuriaOliva, MarcRodríguez-Mena, ManuelSchimmelpfennig, IreneBrynjólfsson, SkaftiSæmundsson, þorsteinnZamorano, José J.Úbeda, JoseAumaître, GeorgesBourlès, DidierKeddadouche, Karim2021-12-27T11:31:14Z20212021-01-01T00:00:00Zinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttp://hdl.handle.net/10451/50562engTanarro, L. M., Palacios, D., Fernández-Fernández, J. M., [et al.] (2021) Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland. Quaternary Science Reviews, 273, 107248. https://doi.org/10.1016/j.quascirev.2021.1072480277-379110.1016/j.quascirev.2021.107248info: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:RCAAP2023-11-08T16:54:50Zoai:repositorio.ul.pt:10451/50562Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T22:02:00.295256Repositório 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 |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland |
title |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland |
spellingShingle |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland Tanarro, Luis M. Iceland Hofsdalur Tröllaskagi peninsula Glacial evolution Debris-covered glaciers Rock glaciers Younger dryas Holocene Holocene thermal maximum |
title_short |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland |
title_full |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland |
title_fullStr |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland |
title_full_unstemmed |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland |
title_sort |
Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland |
author |
Tanarro, Luis M. |
author_facet |
Tanarro, Luis M. Palacios, David Fernández-Fernández, Jose M. Andrés, Nuria Oliva, Marc Rodríguez-Mena, Manuel Schimmelpfennig, Irene Brynjólfsson, Skafti Sæmundsson, þorsteinn Zamorano, José J. Úbeda, Jose Aumaître, Georges Bourlès, Didier Keddadouche, Karim |
author_role |
author |
author2 |
Palacios, David Fernández-Fernández, Jose M. Andrés, Nuria Oliva, Marc Rodríguez-Mena, Manuel Schimmelpfennig, Irene Brynjólfsson, Skafti Sæmundsson, þorsteinn Zamorano, José J. Úbeda, Jose Aumaître, Georges Bourlès, Didier Keddadouche, Karim |
author2_role |
author author author author author author author author author author author author author |
dc.contributor.none.fl_str_mv |
Repositório da Universidade de Lisboa |
dc.contributor.author.fl_str_mv |
Tanarro, Luis M. Palacios, David Fernández-Fernández, Jose M. Andrés, Nuria Oliva, Marc Rodríguez-Mena, Manuel Schimmelpfennig, Irene Brynjólfsson, Skafti Sæmundsson, þorsteinn Zamorano, José J. Úbeda, Jose Aumaître, Georges Bourlès, Didier Keddadouche, Karim |
dc.subject.por.fl_str_mv |
Iceland Hofsdalur Tröllaskagi peninsula Glacial evolution Debris-covered glaciers Rock glaciers Younger dryas Holocene Holocene thermal maximum |
topic |
Iceland Hofsdalur Tröllaskagi peninsula Glacial evolution Debris-covered glaciers Rock glaciers Younger dryas Holocene Holocene thermal maximum |
description |
The aim of this work is to study the process of transformation of debris-free mountain glaciers into debris-covered glaciers and rock glaciers, and to examine the factors driving diverging evolution in similar glacial systems. The study area is the Hofsdalur valley, in the Tröllaskagi peninsula (northern Iceland), where several cirques host a great diversity of glaciers and rock glaciers as well as various glacial landforms. Four adjacent cirques have been analysed through a multidisciplinary approach: geomorphological analysis, boulder surface displacement tracking, quantification of recent glacier changes, three dimensional palaeoglacier reconstruction, equilibrium-line altitude calculations and relative and direct dating methods applied to surface boulders. Dating methods included in situ 36Cl cosmic-ray exposure dating, Schmidt hammer weathering measurements and lichenometric dating. The results confirm that glaciers in Hofsdalur followed an evolution pattern similar to that observed in other cirques in the Tröllaskagi peninsula. During the Younger Dryas (12.9–11.7 ka) many of those cirques hosted debris-free glaciers, whose retreat started in the early Holocene. Distinct retreat dynamics and cirque floor elevation conditioned the subsequent glacial evolution. In some Tröllaskagi cirques, the ice completely covered the headwalls, which consequently did not supply debris onto the glacier surface, which remained debris-free. In most of these cirques, however, glacier retreat enhanced paraglacial processes and the ice-free cirque walls generated a high debris supply onto the glacier surface. As a result, the glaciers evolved towards debris-covered glaciers or rock glaciers, depending on the local topographical setting. In the lower cirques they collapsed immediately after their formation. At higher altitudes, above the lower permafrost limit, these ice-cored landforms have survived until the present day, but they have been stagnant since the Holocene Thermal Maximum, while the heads of these cirques have hosted debris-free glaciers during the Late Holocene. |
publishDate |
2021 |
dc.date.none.fl_str_mv |
2021-12-27T11:31:14Z 2021 2021-01-01T00:00:00Z |
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/10451/50562 |
url |
http://hdl.handle.net/10451/50562 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Tanarro, L. M., Palacios, D., Fernández-Fernández, J. M., [et al.] (2021) Origins of the divergent evolution of mountain glaciers during deglaciation: Hofsdalur cirques, Northern Iceland. Quaternary Science Reviews, 273, 107248. https://doi.org/10.1016/j.quascirev.2021.107248 0277-3791 10.1016/j.quascirev.2021.107248 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier |
publisher.none.fl_str_mv |
Elsevier |
dc.source.none.fl_str_mv |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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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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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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