Regional mid-Pleistocene glaciation in central Patagonia
Southern South America contains a glacial geomorphological record that spans the past million years and has the potential to provide palaeoclimate information for several glacial periods in Earth's history. In central Patagonia, two major outlet glaciers of the former Patagonian Ice Sheet carve...
Published in: | Quaternary Science Reviews |
---|---|
Main Authors: | , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2017
|
Subjects: | |
Online Access: | https://research.manchester.ac.uk/en/publications/d13ad5a1-e030-4f74-861d-684bd77243c1 https://doi.org/10.1016/j.quascirev.2017.03.023 https://pure.manchester.ac.uk/ws/files/78786050/33651882._AAM._Hein.pdf |
id |
ftumanchesterpub:oai:pure.atira.dk:publications/d13ad5a1-e030-4f74-861d-684bd77243c1 |
---|---|
record_format |
openpolar |
spelling |
ftumanchesterpub:oai:pure.atira.dk:publications/d13ad5a1-e030-4f74-861d-684bd77243c1 2023-11-12T04:18:50+01:00 Regional mid-Pleistocene glaciation in central Patagonia Hein, Andrew Cogez, Antoine Darvill, Christopher Mendelova, Monika Kaplan, Michael Herman, Frédéric Dunai, Tibor Norton, Kevin Xu, Sheng Christl, Marcus Rodés, Ángel 2017-05-15 application/pdf https://research.manchester.ac.uk/en/publications/d13ad5a1-e030-4f74-861d-684bd77243c1 https://doi.org/10.1016/j.quascirev.2017.03.023 https://pure.manchester.ac.uk/ws/files/78786050/33651882._AAM._Hein.pdf eng eng info:eu-repo/semantics/openAccess Hein , A , Cogez , A , Darvill , C , Mendelova , M , Kaplan , M , Herman , F , Dunai , T , Norton , K , Xu , S , Christl , M & Rodés , Á 2017 , ' Regional mid-Pleistocene glaciation in central Patagonia ' , Quaternary Science Reviews , vol. 164 , pp. 77-94 . https://doi.org/10.1016/j.quascirev.2017.03.023 Cosmogenic nuclide surface exposure dating Marine isotope stage 8 Glacial chronology Moraine degradation Beryllium-10 Last Glacial Maximum Moraine boulders article 2017 ftumanchesterpub https://doi.org/10.1016/j.quascirev.2017.03.023 2023-10-30T09:13:06Z Southern South America contains a glacial geomorphological record that spans the past million years and has the potential to provide palaeoclimate information for several glacial periods in Earth's history. In central Patagonia, two major outlet glaciers of the former Patagonian Ice Sheet carved deep basins ∼50 km wide and extending over 100 km into the Andean plain east of the mountain front. A succession of nested glacial moraines offers the possibility of determining when the ice lobes advanced and whether such advances occurred synchronously. The existing chronology, which was obtained using different methods in each valley, indicates the penultimate moraines differ in age by a full glacial cycle. Here, we test this hypothesis further using a uniform methodology that combines cosmogenic nuclide ages from moraine boulders, moraine cobbles and outwash cobbles. 10Be concentrations in eighteen outwash cobbles from the Moreno outwash terrace in the Lago Buenos Aires valley yield surface exposure ages of 169–269 ka. We find 10Be inheritance is low and therefore use the oldest surface cobbles to date the deposit at 260–270 ka, which is indistinguishable from the age obtained in the neighbouring Lago Pueyrredón valley. This suggests a regionally significant glaciation during Marine Isotope Stage 8, and broad interhemispheric synchrony of glacial maxima during the mid to late Pleistocene. Finally, we find the dated outwash terrace is 70–100 ka older than the associated moraines. On the basis of geomorphological observations, we suggest this difference can be explained by exhumation of moraine boulders. Article in Journal/Newspaper Ice Sheet The University of Manchester: Research Explorer Quaternary Science Reviews 164 77 94 |
institution |
Open Polar |
collection |
The University of Manchester: Research Explorer |
op_collection_id |
ftumanchesterpub |
language |
English |
topic |
Cosmogenic nuclide surface exposure dating Marine isotope stage 8 Glacial chronology Moraine degradation Beryllium-10 Last Glacial Maximum Moraine boulders |
spellingShingle |
Cosmogenic nuclide surface exposure dating Marine isotope stage 8 Glacial chronology Moraine degradation Beryllium-10 Last Glacial Maximum Moraine boulders Hein, Andrew Cogez, Antoine Darvill, Christopher Mendelova, Monika Kaplan, Michael Herman, Frédéric Dunai, Tibor Norton, Kevin Xu, Sheng Christl, Marcus Rodés, Ángel Regional mid-Pleistocene glaciation in central Patagonia |
topic_facet |
Cosmogenic nuclide surface exposure dating Marine isotope stage 8 Glacial chronology Moraine degradation Beryllium-10 Last Glacial Maximum Moraine boulders |
description |
Southern South America contains a glacial geomorphological record that spans the past million years and has the potential to provide palaeoclimate information for several glacial periods in Earth's history. In central Patagonia, two major outlet glaciers of the former Patagonian Ice Sheet carved deep basins ∼50 km wide and extending over 100 km into the Andean plain east of the mountain front. A succession of nested glacial moraines offers the possibility of determining when the ice lobes advanced and whether such advances occurred synchronously. The existing chronology, which was obtained using different methods in each valley, indicates the penultimate moraines differ in age by a full glacial cycle. Here, we test this hypothesis further using a uniform methodology that combines cosmogenic nuclide ages from moraine boulders, moraine cobbles and outwash cobbles. 10Be concentrations in eighteen outwash cobbles from the Moreno outwash terrace in the Lago Buenos Aires valley yield surface exposure ages of 169–269 ka. We find 10Be inheritance is low and therefore use the oldest surface cobbles to date the deposit at 260–270 ka, which is indistinguishable from the age obtained in the neighbouring Lago Pueyrredón valley. This suggests a regionally significant glaciation during Marine Isotope Stage 8, and broad interhemispheric synchrony of glacial maxima during the mid to late Pleistocene. Finally, we find the dated outwash terrace is 70–100 ka older than the associated moraines. On the basis of geomorphological observations, we suggest this difference can be explained by exhumation of moraine boulders. |
format |
Article in Journal/Newspaper |
author |
Hein, Andrew Cogez, Antoine Darvill, Christopher Mendelova, Monika Kaplan, Michael Herman, Frédéric Dunai, Tibor Norton, Kevin Xu, Sheng Christl, Marcus Rodés, Ángel |
author_facet |
Hein, Andrew Cogez, Antoine Darvill, Christopher Mendelova, Monika Kaplan, Michael Herman, Frédéric Dunai, Tibor Norton, Kevin Xu, Sheng Christl, Marcus Rodés, Ángel |
author_sort |
Hein, Andrew |
title |
Regional mid-Pleistocene glaciation in central Patagonia |
title_short |
Regional mid-Pleistocene glaciation in central Patagonia |
title_full |
Regional mid-Pleistocene glaciation in central Patagonia |
title_fullStr |
Regional mid-Pleistocene glaciation in central Patagonia |
title_full_unstemmed |
Regional mid-Pleistocene glaciation in central Patagonia |
title_sort |
regional mid-pleistocene glaciation in central patagonia |
publishDate |
2017 |
url |
https://research.manchester.ac.uk/en/publications/d13ad5a1-e030-4f74-861d-684bd77243c1 https://doi.org/10.1016/j.quascirev.2017.03.023 https://pure.manchester.ac.uk/ws/files/78786050/33651882._AAM._Hein.pdf |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Hein , A , Cogez , A , Darvill , C , Mendelova , M , Kaplan , M , Herman , F , Dunai , T , Norton , K , Xu , S , Christl , M & Rodés , Á 2017 , ' Regional mid-Pleistocene glaciation in central Patagonia ' , Quaternary Science Reviews , vol. 164 , pp. 77-94 . https://doi.org/10.1016/j.quascirev.2017.03.023 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.quascirev.2017.03.023 |
container_title |
Quaternary Science Reviews |
container_volume |
164 |
container_start_page |
77 |
op_container_end_page |
94 |
_version_ |
1782335380754792448 |