干旱区生态环境知识资源中心(Arid): Sedimentary and geomorphic evidence of Saharan megalakes: A synthesis

Arid

DOI	10.1016/j.quascirev.2021.107318
	Sedimentary and geomorphic evidence of Saharan megalakes: A synthesis
	Drake, N. A.; Candy, I; Breeze, P.; Armitage, S. J.; Gasmi, N.; Schwenninger, J. L.; Peat, D.; Manning, K.
通讯作者	Drake, NA (corresponding author), Kings Coll London, Dept Geog, London, England.
来源期刊	QUATERNARY SCIENCE REVIEWS
ISSN	0277-3791
EISSN	1873-457X
出版年	2022
卷号	276
英文摘要	It has long been recognised that the Sahara Desert contains sediment, landform and palaeoecological evidence for phases of increased humidity during the Quaternary period. Many authors have also suggested that during some of these humid periods very large lakes, termed megalakes, developed in several basins within the Sahara. Recent work has questioned their existence. In particular it has been argued that the lack of well-developed and spatially extensive shorelines in these basins suggests that discrete groundwater and spring deposits have been misinterpreted as evidence for megalakes. In this paper we re-evaluate the evidence used to identify megalakes. Firstly, we apply a comprehensive remote sensing and GIS analyses to the megalake shorelines, their catchments and the wider Sahara. This not only supports the previously proposed existence of numerous megalakes, but also indicates a previously unrecognised megalake in the Niger Inland Delta region, here named Megalake Timbuktu. Secondly, we review the geomorphic and sedimentary evidence for the megalakes, highlighting the importance of the sedimentary record in identifying lake highstands, particularly through the example of the Chotts Megalake in southern Tunisia where we provide new sedimentary information on lake shorelines. This analysis demonstrates that in much of the Sahara the dynamic aeolian systems preclude the preservation of well-developed shorelines, but the distribution of fragmented geomorphic features and localised lake deposits provide robust evidence for Quaternary megalake formation. The paper concludes by highlighting that although extensive evidence for Saharan megalake formation exists, the current chronology of lake highstands indicates that the vast majority date to Marine Isotope Stage (MIS) 5 or earlier. Only megalakes Chad and Timbuktu, which derive much of their water from outside the desert, show evidence for Holocene (African Humid Period or AHP) shorelines. The AHP record of the other megalakes indicate the existence of much smaller water bodies than those that developed earlier in the Pleistocene indicating that it was significantly drier than these earlier humid phases. (C) 2021 Elsevier Ltd. All rights reserved.
英文关键词	Sahara desert Megalake Remote sensing Digital elevation model Sedimentology Shorelines
类型	Article
语种	英语
收录类别	SCI-E ; SSCI
WOS记录号	WOS:000731929600016
WOS关键词	LACUSTRINE SEDIMENTS ; SOUTHERN TUNISIA ; EASTERN SAHARA ; WESTERN SAHARA ; FAZZAN BASIN ; CLIMATE ; MONSOON ; CHAD ; FLUCTUATIONS ; OCCUPATION
WOS类目	Geography, Physical ; Geosciences, Multidisciplinary
WOS研究方向	Physical Geography ; Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/374488
作者单位	[Drake, N. A.; Breeze, P.; Manning, K.] Kings Coll London, Dept Geog, London, England; [Drake, N. A.] Max Planck Inst Sci Human Hist, Dept Archaeol, Jena, Germany; [Candy, I; Armitage, S. J.] Royal Holloway Univ London, Ctr Quaternary Res, Dept Geog, Egham, Surrey, England; [Armitage, S. J.] Univ Bergen, SFF Ctr Early Sapiens Behav SapienCE, Post Box 7805, N-5020 Bergen, Norway; [Gasmi, N.] Univ Sousse, Fac Letters & Human Sci Sousse, Sousse, Tunisia; [Gasmi, N.] Univ Tunis, Lab Cartog Geomorphol Milieux Environm & Dynam CG, Tunis, Tunisia; [Schwenninger, J. L.; Peat, D.] Univ Oxford, Sch Archaeol, Res Lab Archaeol & Hist Art, Oxford, England
推荐引用方式 GB/T 7714	Drake, N. A.,Candy, I,Breeze, P.,et al. Sedimentary and geomorphic evidence of Saharan megalakes: A synthesis[J],2022,276.
APA	Drake, N. A..,Candy, I.,Breeze, P..,Armitage, S. J..,Gasmi, N..,...&Manning, K..(2022).Sedimentary and geomorphic evidence of Saharan megalakes: A synthesis.QUATERNARY SCIENCE REVIEWS,276.
MLA	Drake, N. A.,et al."Sedimentary and geomorphic evidence of Saharan megalakes: A synthesis".QUATERNARY SCIENCE REVIEWS 276(2022).