Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach
We propose a novel method to evaluate regional palaeoclimate that can be used to alleviate the problems caused by the discontinuous nature of palaeoenvironmental data found in deserts. The technique involves processing satellite imagery and DEM's to map past rivers, catchments and evaluate the...
Published in: | Quaternary Science Reviews |
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Language: | English |
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2018
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Online Access: | https://kclpure.kcl.ac.uk/portal/en/publications/reconstructing-palaeoclimate-and-hydrological-fluctuations-in-the-fezzan-basin-southern-libya-since-130-ka(1594be8e-ba1b-4d87-9fe3-93a675e75f3b).html https://doi.org/10.1016/j.quascirev.2018.09.042 https://kclpure.kcl.ac.uk/ws/files/102298795/Reconstructing_palaeoclimate_and_hydrological_DRAKE_Accepted28September2018_GREEN_AAM.pdf http://www.scopus.com/inward/record.url?scp=85054911818&partnerID=8YFLogxK |
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ftkingscollondon:oai:pure.atira.dk:publications/1594be8e-ba1b-4d87-9fe3-93a675e75f3b 2023-05-15T17:36:44+02:00 Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach Drake, Nick A. Lem, Rachael E. Armitage, Simon J. Breeze, Paul Francke, Jan El-Hawat, Ahmed S. Salem, Mustafa J. Hounslow, Mark W. White, Kevin 2018-11-15 application/pdf https://kclpure.kcl.ac.uk/portal/en/publications/reconstructing-palaeoclimate-and-hydrological-fluctuations-in-the-fezzan-basin-southern-libya-since-130-ka(1594be8e-ba1b-4d87-9fe3-93a675e75f3b).html https://doi.org/10.1016/j.quascirev.2018.09.042 https://kclpure.kcl.ac.uk/ws/files/102298795/Reconstructing_palaeoclimate_and_hydrological_DRAKE_Accepted28September2018_GREEN_AAM.pdf http://www.scopus.com/inward/record.url?scp=85054911818&partnerID=8YFLogxK eng eng info:eu-repo/semantics/openAccess Drake , N A , Lem , R E , Armitage , S J , Breeze , P , Francke , J , El-Hawat , A S , Salem , M J , Hounslow , M W & White , K 2018 , ' Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka : A catchment-based approach ' , QUATERNARY SCIENCE REVIEWS , vol. 200 , pp. 376-394 . https://doi.org/10.1016/j.quascirev.2018.09.042 Holocene Lake evaluation index Middle east Optical methods Palaeohydrology Paleoclimatology Pleistocene Sahara article 2018 ftkingscollondon https://doi.org/10.1016/j.quascirev.2018.09.042 2022-10-14T10:41:25Z We propose a novel method to evaluate regional palaeoclimate that can be used to alleviate the problems caused by the discontinuous nature of palaeoenvironmental data found in deserts. The technique involves processing satellite imagery and DEM's to map past rivers, catchments and evaluate the areas and volumes of palaeolakes. This information is used to determine the new Lake Evaluation Index (LEI) that allows a qualitative estimate of the amount of sediment received by lakes and how long-lived those lakes are. Lakes with considerable longevity and large sediment stores are selected for study. Validation is performed using image interpretation of remote sensing data, UltraGPR surveys and fieldwork. These techniques are also used to identify and study spring deposits and fluvial landforms that provide valuable palaeoclimate information. The method is applied to the Fezzan Basin in southern Libya focusing on the Wadi ash Shati and Wadi el-Agial catchments. Results indicate that the palaeohydrology is accurately mapped except within dune fields. We analysed the sedimentology of the key deposits identified by this methodology, developing a chronology using optically stimulated luminescence (OSL) and radiocarbon dating. We find evidence for relatively humid conditions during MIS 5c/d and e, as well as during the early to middle Holocene. Larger lakes and more extensive river systems were present during MIS 5 than are found during the Holocene, suggestive of greater humidity. The Holocene humid period started at ∼11 ka and continued until ∼5 ka being interrupted by abrupt periods of aridity at ∼8.2 ka and ∼6 ka that coincide with North Atlantic cooling. After each of these arid events the climate was less humid than previously, suggesting that they were superimposed upon an overall drying trend. The termination of the Holocene humid period in the Sahara has received much scrutiny in recent years, and sediments of Palaeolake Shati provide a continuous record of this. We do not find evidence to support the hypothesis ... Article in Journal/Newspaper North Atlantic King's College, London: Research Portal New Lake ENVELOPE(-109.468,-109.468,62.684,62.684) Quaternary Science Reviews 200 376 394 |
institution |
Open Polar |
collection |
King's College, London: Research Portal |
op_collection_id |
ftkingscollondon |
language |
English |
topic |
Holocene Lake evaluation index Middle east Optical methods Palaeohydrology Paleoclimatology Pleistocene Sahara |
spellingShingle |
Holocene Lake evaluation index Middle east Optical methods Palaeohydrology Paleoclimatology Pleistocene Sahara Drake, Nick A. Lem, Rachael E. Armitage, Simon J. Breeze, Paul Francke, Jan El-Hawat, Ahmed S. Salem, Mustafa J. Hounslow, Mark W. White, Kevin Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach |
topic_facet |
Holocene Lake evaluation index Middle east Optical methods Palaeohydrology Paleoclimatology Pleistocene Sahara |
description |
We propose a novel method to evaluate regional palaeoclimate that can be used to alleviate the problems caused by the discontinuous nature of palaeoenvironmental data found in deserts. The technique involves processing satellite imagery and DEM's to map past rivers, catchments and evaluate the areas and volumes of palaeolakes. This information is used to determine the new Lake Evaluation Index (LEI) that allows a qualitative estimate of the amount of sediment received by lakes and how long-lived those lakes are. Lakes with considerable longevity and large sediment stores are selected for study. Validation is performed using image interpretation of remote sensing data, UltraGPR surveys and fieldwork. These techniques are also used to identify and study spring deposits and fluvial landforms that provide valuable palaeoclimate information. The method is applied to the Fezzan Basin in southern Libya focusing on the Wadi ash Shati and Wadi el-Agial catchments. Results indicate that the palaeohydrology is accurately mapped except within dune fields. We analysed the sedimentology of the key deposits identified by this methodology, developing a chronology using optically stimulated luminescence (OSL) and radiocarbon dating. We find evidence for relatively humid conditions during MIS 5c/d and e, as well as during the early to middle Holocene. Larger lakes and more extensive river systems were present during MIS 5 than are found during the Holocene, suggestive of greater humidity. The Holocene humid period started at ∼11 ka and continued until ∼5 ka being interrupted by abrupt periods of aridity at ∼8.2 ka and ∼6 ka that coincide with North Atlantic cooling. After each of these arid events the climate was less humid than previously, suggesting that they were superimposed upon an overall drying trend. The termination of the Holocene humid period in the Sahara has received much scrutiny in recent years, and sediments of Palaeolake Shati provide a continuous record of this. We do not find evidence to support the hypothesis ... |
format |
Article in Journal/Newspaper |
author |
Drake, Nick A. Lem, Rachael E. Armitage, Simon J. Breeze, Paul Francke, Jan El-Hawat, Ahmed S. Salem, Mustafa J. Hounslow, Mark W. White, Kevin |
author_facet |
Drake, Nick A. Lem, Rachael E. Armitage, Simon J. Breeze, Paul Francke, Jan El-Hawat, Ahmed S. Salem, Mustafa J. Hounslow, Mark W. White, Kevin |
author_sort |
Drake, Nick A. |
title |
Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach |
title_short |
Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach |
title_full |
Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach |
title_fullStr |
Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach |
title_full_unstemmed |
Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka:A catchment-based approach |
title_sort |
reconstructing palaeoclimate and hydrological fluctuations in the fezzan basin (southern libya) since 130 ka:a catchment-based approach |
publishDate |
2018 |
url |
https://kclpure.kcl.ac.uk/portal/en/publications/reconstructing-palaeoclimate-and-hydrological-fluctuations-in-the-fezzan-basin-southern-libya-since-130-ka(1594be8e-ba1b-4d87-9fe3-93a675e75f3b).html https://doi.org/10.1016/j.quascirev.2018.09.042 https://kclpure.kcl.ac.uk/ws/files/102298795/Reconstructing_palaeoclimate_and_hydrological_DRAKE_Accepted28September2018_GREEN_AAM.pdf http://www.scopus.com/inward/record.url?scp=85054911818&partnerID=8YFLogxK |
long_lat |
ENVELOPE(-109.468,-109.468,62.684,62.684) |
geographic |
New Lake |
geographic_facet |
New Lake |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Drake , N A , Lem , R E , Armitage , S J , Breeze , P , Francke , J , El-Hawat , A S , Salem , M J , Hounslow , M W & White , K 2018 , ' Reconstructing palaeoclimate and hydrological fluctuations in the Fezzan Basin (southern Libya) since 130 ka : A catchment-based approach ' , QUATERNARY SCIENCE REVIEWS , vol. 200 , pp. 376-394 . https://doi.org/10.1016/j.quascirev.2018.09.042 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.quascirev.2018.09.042 |
container_title |
Quaternary Science Reviews |
container_volume |
200 |
container_start_page |
376 |
op_container_end_page |
394 |
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1766136316749152256 |