Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego
- Autores
- Unkel, Ingmar; Fernández, Marilén; Björck, Svante; Ljung, Karl; Wohlfarth, Barbara
- Año de publicación
- 2010
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- Southernmost Patagonia, located at the relatively narrow passage between Antarctica and South America, is a highly sensitive region for recording meridional and zonal changes in the pattern of oceanic and atmospheric circulation. The island of Isla de los Estados, situated at 54.5°S, 64°W, east of Argentinean Tierra del Fuego, provides an exceptional possibility, to investigate terrestrial records of atmospheric conditions in an oceanic setting during the last deglaciation and the Holocene. Here we present geochemical and diatom analyses from 10 600 to c. 1500 cal BP of one sequence (LGB) with peat, lake sediments and lagoon deposits at the northern coast of the island, and a lake sediment sequence (CAS) 3 km further inland. The data comprise TC, TN, loss on ignition analyses and continuous XRF scanning as well as age–depth modeling based on AMS-14C dating on both cores. Diatom analysis of the CAS record complements the geochemical proxies. During the Holocene, our two sites have been impacted by two different forcings: changes in the regional climate regime largely influenced by the varying strength and position of the Southern Hemisphere Westerlies (SHW), while relative sea-level changes affected the deposits of the coastal site. In concert with the onset of the Antarctic thermal optimum, our data suggest fairly warm conditions and the establishment of denser peat and forest vegetation on the island c. 10 600 cal BP. Between 8500 and 4500 cal BP geochemistry and diatoms from the CAS record indicate stronger Westerlies at this latitude, which means higher wind speed or higher storm frequency and more precipitation, resulting in more pronounced surface run-off. After 4500 cal BP, the geochemical proxies and large changes in diatom assemblages indicate a decrease in precipitation, weaker winds and possibly cooler conditions, probably as an effect of weaker SHW and/or a latitudinal shift. The depositional environment of CAS changed from gyttja to peat around 1000 cal BP. At LGB, the onset of gyttja sedimentation around 7900 cal BP shows that the former wet land with peat accumulation had become a lake with a fairly rapid sedimentation. The chemical data from LGB imply a gradually increasing marine influence, probably as an effect of both rising sea level and increased impact of storms and maximum high tides. After a marine high-stand during the mid-Holocene, the LGB site returned into a peat bog again around 3400 cal BP. Our data suggest that since then relative sea level first dropped back below present sea level followed by a rise to present day sea level.
Fil: Unkel, Ingmar . Lund University; Suecia. Kiel University. Institute for Ecosystem Research; Alemania
Fil: Fernández, Marilén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Lund University; Suecia
Fil: Björck, Svante . Lund University; Suecia
Fil: Ljung, Karl. University of Bristol; Reino Unido. Lund University; Suecia
Fil: Wohlfarth, Barbara . Stockholms Universitet; Suecia - Materia
-
Holocene
Lake Sediments
Peat
Diatom Analysis
Xrf
Paleoclimate
Southern Westerlies
Sea Level Changes
Tierra del Fuego - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc-nd/2.5/ar/
- Repositorio
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/12693
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Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del FuegoUnkel, Ingmar Fernández, MarilénBjörck, Svante Ljung, KarlWohlfarth, Barbara HoloceneLake SedimentsPeatDiatom AnalysisXrfPaleoclimateSouthern WesterliesSea Level ChangesTierra del Fuegohttps://purl.org/becyt/ford/1.5https://purl.org/becyt/ford/1Southernmost Patagonia, located at the relatively narrow passage between Antarctica and South America, is a highly sensitive region for recording meridional and zonal changes in the pattern of oceanic and atmospheric circulation. The island of Isla de los Estados, situated at 54.5°S, 64°W, east of Argentinean Tierra del Fuego, provides an exceptional possibility, to investigate terrestrial records of atmospheric conditions in an oceanic setting during the last deglaciation and the Holocene. Here we present geochemical and diatom analyses from 10 600 to c. 1500 cal BP of one sequence (LGB) with peat, lake sediments and lagoon deposits at the northern coast of the island, and a lake sediment sequence (CAS) 3 km further inland. The data comprise TC, TN, loss on ignition analyses and continuous XRF scanning as well as age–depth modeling based on AMS-14C dating on both cores. Diatom analysis of the CAS record complements the geochemical proxies. During the Holocene, our two sites have been impacted by two different forcings: changes in the regional climate regime largely influenced by the varying strength and position of the Southern Hemisphere Westerlies (SHW), while relative sea-level changes affected the deposits of the coastal site. In concert with the onset of the Antarctic thermal optimum, our data suggest fairly warm conditions and the establishment of denser peat and forest vegetation on the island c. 10 600 cal BP. Between 8500 and 4500 cal BP geochemistry and diatoms from the CAS record indicate stronger Westerlies at this latitude, which means higher wind speed or higher storm frequency and more precipitation, resulting in more pronounced surface run-off. After 4500 cal BP, the geochemical proxies and large changes in diatom assemblages indicate a decrease in precipitation, weaker winds and possibly cooler conditions, probably as an effect of weaker SHW and/or a latitudinal shift. The depositional environment of CAS changed from gyttja to peat around 1000 cal BP. At LGB, the onset of gyttja sedimentation around 7900 cal BP shows that the former wet land with peat accumulation had become a lake with a fairly rapid sedimentation. The chemical data from LGB imply a gradually increasing marine influence, probably as an effect of both rising sea level and increased impact of storms and maximum high tides. After a marine high-stand during the mid-Holocene, the LGB site returned into a peat bog again around 3400 cal BP. Our data suggest that since then relative sea level first dropped back below present sea level followed by a rise to present day sea level.Fil: Unkel, Ingmar . Lund University; Suecia. Kiel University. Institute for Ecosystem Research; AlemaniaFil: Fernández, Marilén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Lund University; SueciaFil: Björck, Svante . Lund University; SueciaFil: Ljung, Karl. University of Bristol; Reino Unido. Lund University; SueciaFil: Wohlfarth, Barbara . Stockholms Universitet; SueciaElsevier Science2010-12info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/12693Unkel, Ingmar ; Fernández, Marilén; Björck, Svante ; Ljung, Karl; Wohlfarth, Barbara ; Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego; Elsevier Science; Global And Planetary Change; 74; 3-4; 12-2010; 99-1130921-8181enginfo:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0921818110001542info:eu-repo/semantics/altIdentifier/doi/10.1016/j.gloplacha.2010.07.003info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-nd/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-03T09:52:05Zoai:ri.conicet.gov.ar:11336/12693instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-03 09:52:05.468CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
dc.title.none.fl_str_mv |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego |
title |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego |
spellingShingle |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego Unkel, Ingmar Holocene Lake Sediments Peat Diatom Analysis Xrf Paleoclimate Southern Westerlies Sea Level Changes Tierra del Fuego |
title_short |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego |
title_full |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego |
title_fullStr |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego |
title_full_unstemmed |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego |
title_sort |
Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego |
dc.creator.none.fl_str_mv |
Unkel, Ingmar Fernández, Marilén Björck, Svante Ljung, Karl Wohlfarth, Barbara |
author |
Unkel, Ingmar |
author_facet |
Unkel, Ingmar Fernández, Marilén Björck, Svante Ljung, Karl Wohlfarth, Barbara |
author_role |
author |
author2 |
Fernández, Marilén Björck, Svante Ljung, Karl Wohlfarth, Barbara |
author2_role |
author author author author |
dc.subject.none.fl_str_mv |
Holocene Lake Sediments Peat Diatom Analysis Xrf Paleoclimate Southern Westerlies Sea Level Changes Tierra del Fuego |
topic |
Holocene Lake Sediments Peat Diatom Analysis Xrf Paleoclimate Southern Westerlies Sea Level Changes Tierra del Fuego |
purl_subject.fl_str_mv |
https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 |
dc.description.none.fl_txt_mv |
Southernmost Patagonia, located at the relatively narrow passage between Antarctica and South America, is a highly sensitive region for recording meridional and zonal changes in the pattern of oceanic and atmospheric circulation. The island of Isla de los Estados, situated at 54.5°S, 64°W, east of Argentinean Tierra del Fuego, provides an exceptional possibility, to investigate terrestrial records of atmospheric conditions in an oceanic setting during the last deglaciation and the Holocene. Here we present geochemical and diatom analyses from 10 600 to c. 1500 cal BP of one sequence (LGB) with peat, lake sediments and lagoon deposits at the northern coast of the island, and a lake sediment sequence (CAS) 3 km further inland. The data comprise TC, TN, loss on ignition analyses and continuous XRF scanning as well as age–depth modeling based on AMS-14C dating on both cores. Diatom analysis of the CAS record complements the geochemical proxies. During the Holocene, our two sites have been impacted by two different forcings: changes in the regional climate regime largely influenced by the varying strength and position of the Southern Hemisphere Westerlies (SHW), while relative sea-level changes affected the deposits of the coastal site. In concert with the onset of the Antarctic thermal optimum, our data suggest fairly warm conditions and the establishment of denser peat and forest vegetation on the island c. 10 600 cal BP. Between 8500 and 4500 cal BP geochemistry and diatoms from the CAS record indicate stronger Westerlies at this latitude, which means higher wind speed or higher storm frequency and more precipitation, resulting in more pronounced surface run-off. After 4500 cal BP, the geochemical proxies and large changes in diatom assemblages indicate a decrease in precipitation, weaker winds and possibly cooler conditions, probably as an effect of weaker SHW and/or a latitudinal shift. The depositional environment of CAS changed from gyttja to peat around 1000 cal BP. At LGB, the onset of gyttja sedimentation around 7900 cal BP shows that the former wet land with peat accumulation had become a lake with a fairly rapid sedimentation. The chemical data from LGB imply a gradually increasing marine influence, probably as an effect of both rising sea level and increased impact of storms and maximum high tides. After a marine high-stand during the mid-Holocene, the LGB site returned into a peat bog again around 3400 cal BP. Our data suggest that since then relative sea level first dropped back below present sea level followed by a rise to present day sea level. Fil: Unkel, Ingmar . Lund University; Suecia. Kiel University. Institute for Ecosystem Research; Alemania Fil: Fernández, Marilén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Lund University; Suecia Fil: Björck, Svante . Lund University; Suecia Fil: Ljung, Karl. University of Bristol; Reino Unido. Lund University; Suecia Fil: Wohlfarth, Barbara . Stockholms Universitet; Suecia |
description |
Southernmost Patagonia, located at the relatively narrow passage between Antarctica and South America, is a highly sensitive region for recording meridional and zonal changes in the pattern of oceanic and atmospheric circulation. The island of Isla de los Estados, situated at 54.5°S, 64°W, east of Argentinean Tierra del Fuego, provides an exceptional possibility, to investigate terrestrial records of atmospheric conditions in an oceanic setting during the last deglaciation and the Holocene. Here we present geochemical and diatom analyses from 10 600 to c. 1500 cal BP of one sequence (LGB) with peat, lake sediments and lagoon deposits at the northern coast of the island, and a lake sediment sequence (CAS) 3 km further inland. The data comprise TC, TN, loss on ignition analyses and continuous XRF scanning as well as age–depth modeling based on AMS-14C dating on both cores. Diatom analysis of the CAS record complements the geochemical proxies. During the Holocene, our two sites have been impacted by two different forcings: changes in the regional climate regime largely influenced by the varying strength and position of the Southern Hemisphere Westerlies (SHW), while relative sea-level changes affected the deposits of the coastal site. In concert with the onset of the Antarctic thermal optimum, our data suggest fairly warm conditions and the establishment of denser peat and forest vegetation on the island c. 10 600 cal BP. Between 8500 and 4500 cal BP geochemistry and diatoms from the CAS record indicate stronger Westerlies at this latitude, which means higher wind speed or higher storm frequency and more precipitation, resulting in more pronounced surface run-off. After 4500 cal BP, the geochemical proxies and large changes in diatom assemblages indicate a decrease in precipitation, weaker winds and possibly cooler conditions, probably as an effect of weaker SHW and/or a latitudinal shift. The depositional environment of CAS changed from gyttja to peat around 1000 cal BP. At LGB, the onset of gyttja sedimentation around 7900 cal BP shows that the former wet land with peat accumulation had become a lake with a fairly rapid sedimentation. The chemical data from LGB imply a gradually increasing marine influence, probably as an effect of both rising sea level and increased impact of storms and maximum high tides. After a marine high-stand during the mid-Holocene, the LGB site returned into a peat bog again around 3400 cal BP. Our data suggest that since then relative sea level first dropped back below present sea level followed by a rise to present day sea level. |
publishDate |
2010 |
dc.date.none.fl_str_mv |
2010-12 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://hdl.handle.net/11336/12693 Unkel, Ingmar ; Fernández, Marilén; Björck, Svante ; Ljung, Karl; Wohlfarth, Barbara ; Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego; Elsevier Science; Global And Planetary Change; 74; 3-4; 12-2010; 99-113 0921-8181 |
url |
http://hdl.handle.net/11336/12693 |
identifier_str_mv |
Unkel, Ingmar ; Fernández, Marilén; Björck, Svante ; Ljung, Karl; Wohlfarth, Barbara ; Records of environmental changes during the Holocene from Isla de los Estados (54.4°S), southeastern Tierra del Fuego; Elsevier Science; Global And Planetary Change; 74; 3-4; 12-2010; 99-113 0921-8181 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/url/http://www.sciencedirect.com/science/article/pii/S0921818110001542 info:eu-repo/semantics/altIdentifier/doi/10.1016/j.gloplacha.2010.07.003 |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-nd/2.5/ar/ |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
https://creativecommons.org/licenses/by-nc-nd/2.5/ar/ |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier Science |
publisher.none.fl_str_mv |
Elsevier Science |
dc.source.none.fl_str_mv |
reponame:CONICET Digital (CONICET) instname:Consejo Nacional de Investigaciones Científicas y Técnicas |
reponame_str |
CONICET Digital (CONICET) |
collection |
CONICET Digital (CONICET) |
instname_str |
Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.name.fl_str_mv |
CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.mail.fl_str_mv |
dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar |
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1842269134967013376 |
score |
13.13397 |