Quaternary glaciation of the Bale Mountains, Ethiopia
Abstract Central Ethiopia comprises a high plateau at 2000–3000 m, formed from Tertiary lava flows and bisected by the Eastern African Rift. Ten volcanic mountains rise to altitudes of just over 4000 m, but on only three has Quaternary glaciation been substantiated by published field observations. O...
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crwiley:10.1002/jqs.931 2024-09-30T14:36:27+00:00 Quaternary glaciation of the Bale Mountains, Ethiopia Osmaston, Henry A. Mitchell, Wishart A. Osmaston, J. A. Nigel 2005 http://dx.doi.org/10.1002/jqs.931 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.931 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.931 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Quaternary Science volume 20, issue 6, page 593-606 ISSN 0267-8179 1099-1417 journal-article 2005 crwiley https://doi.org/10.1002/jqs.931 2024-09-19T04:19:10Z Abstract Central Ethiopia comprises a high plateau at 2000–3000 m, formed from Tertiary lava flows and bisected by the Eastern African Rift. Ten volcanic mountains rise to altitudes of just over 4000 m, but on only three has Quaternary glaciation been substantiated by published field observations. On the Bale Mountains (4400 m), a previous report based on limited evidence proposed an ice‐cap extending to 600 km 2 . Based on aerial photographs and ground surveys, this paper reports evidence of a more complex situation. A wide spread of large erratic boulders on the plateau records a central ice cap of 30 km 2 , though ice probably extended for a further 40 km 2 . Further north two groups of deeply incised and clearly glaciated valleys contain moraines and roches moutonnées (60 km 2 ). On interfluves between them and on the open north slopes are moraines from an earlier stage of the same glaciation or from a distinct older event. Altogether about 180 km 2 may have been glaciated. Cores dated by 14 C from inside and outside the glaciated area suggest that at least the northern valley glaciers may date from the Last Glacial Maximum. Estimated equilibrium line altitudes for these glaciers and the ice‐cap are 3750–4230 m. Copyright © 2005 John Wiley & Sons, Ltd. Article in Journal/Newspaper Ice cap Wiley Online Library Journal of Quaternary Science 20 6 593 606 |
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Wiley Online Library |
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English |
description |
Abstract Central Ethiopia comprises a high plateau at 2000–3000 m, formed from Tertiary lava flows and bisected by the Eastern African Rift. Ten volcanic mountains rise to altitudes of just over 4000 m, but on only three has Quaternary glaciation been substantiated by published field observations. On the Bale Mountains (4400 m), a previous report based on limited evidence proposed an ice‐cap extending to 600 km 2 . Based on aerial photographs and ground surveys, this paper reports evidence of a more complex situation. A wide spread of large erratic boulders on the plateau records a central ice cap of 30 km 2 , though ice probably extended for a further 40 km 2 . Further north two groups of deeply incised and clearly glaciated valleys contain moraines and roches moutonnées (60 km 2 ). On interfluves between them and on the open north slopes are moraines from an earlier stage of the same glaciation or from a distinct older event. Altogether about 180 km 2 may have been glaciated. Cores dated by 14 C from inside and outside the glaciated area suggest that at least the northern valley glaciers may date from the Last Glacial Maximum. Estimated equilibrium line altitudes for these glaciers and the ice‐cap are 3750–4230 m. Copyright © 2005 John Wiley & Sons, Ltd. |
format |
Article in Journal/Newspaper |
author |
Osmaston, Henry A. Mitchell, Wishart A. Osmaston, J. A. Nigel |
spellingShingle |
Osmaston, Henry A. Mitchell, Wishart A. Osmaston, J. A. Nigel Quaternary glaciation of the Bale Mountains, Ethiopia |
author_facet |
Osmaston, Henry A. Mitchell, Wishart A. Osmaston, J. A. Nigel |
author_sort |
Osmaston, Henry A. |
title |
Quaternary glaciation of the Bale Mountains, Ethiopia |
title_short |
Quaternary glaciation of the Bale Mountains, Ethiopia |
title_full |
Quaternary glaciation of the Bale Mountains, Ethiopia |
title_fullStr |
Quaternary glaciation of the Bale Mountains, Ethiopia |
title_full_unstemmed |
Quaternary glaciation of the Bale Mountains, Ethiopia |
title_sort |
quaternary glaciation of the bale mountains, ethiopia |
publisher |
Wiley |
publishDate |
2005 |
url |
http://dx.doi.org/10.1002/jqs.931 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.931 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.931 |
genre |
Ice cap |
genre_facet |
Ice cap |
op_source |
Journal of Quaternary Science volume 20, issue 6, page 593-606 ISSN 0267-8179 1099-1417 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/jqs.931 |
container_title |
Journal of Quaternary Science |
container_volume |
20 |
container_issue |
6 |
container_start_page |
593 |
op_container_end_page |
606 |
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1811639498151297024 |