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Hydrodynamics in Holocene Lake Mega-Chad

  • Frédéric Bouchette (a1) (a2), Mathieu Schuster (a3), Jean-François Ghienne (a4), Cléa Denamiel (a5), Claude Roquin (a4), Abderamane Moussa (a3) (a4), Patrick Marsaleix (a6) and Philippe Duringer (a4)...
Abstract

Holocene Lake Mega-Chad (LMC) was the largest late Quaternary water-body in Africa. The development of this giant paleo-lake is related to a northward shift of the isohyetes interpreted as evidence for an enhanced Monsoon (African Humid Period). Numerous preserved coastal features have been described all around the LMC shore. Such features reveal the main paleo-hydrodynamical tendencies. In the context of a closed water-body like LMC, hydrodynamics are forced mainly by winds. We use a three-dimensional numerical model (SYMPHONIE) to simulate the mean hydrodynamics in LMC under both Harmattan-like (northeasterly trade winds) and Monsoon-like (southwesterly winds) forcings. The northern part of LMC displays coastal features, such as sand spits, that are consistent with the simulations forced by Harmattan-like winds. Geomorphic features related to Monsoon-driven hydrodynamics are not clearly expressed. They could have developed during the early stage of LMC but subsequently reworked. At the time of sand-spit building, Harmattan-like driven hydrodynamics prevailed and related coastal features were preferentially preserved in the sedimentary record.

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Corresponding author
*Corresponding author.E-mail addresses: bouchette@gm.univ-montp2.fr (F. Bouchette), mathieu.schuster@univ-poitiers.fr (M. Schuster).
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H. Akima , (1970). A new method of interpolation and smooth curve fitting based on local procedures. J. ACM 17, 4, 589602.

S.J. Armitage , N.A. Drake , S. Stokes , A. El-Hawat , M.J. Salem , K. White , P. Turner , S.J. McLaren , (2007). Multiple phases of North African humidity recorded in lacustrine sediments from the Fazzan Basin, Libyan Sahara. Quaternary Geochronology 2, 181186.

J. Bouffard , S. Vignudelli , M. Herrmann , F. Lyard , P. Marsaleix , Y. M"nard , P. Cipollini , (2008). Comparison of ocean dynamics with a regional circulation model and improved altimetry in the north-western Mediterranean. Terrestrial, Atmospheric and Oceanic Sciences 19, 119.10.3319/TAO.2008.19.1.2.117(SA).

C.S. Bristow , N. Drake , S. Armitage , (2009). Deflation in the dustiest place on Earth: the Bodélé Depression, Chad. Geomorphology 105, 1-2, 5058.

K. Burke , (1976). The Chad Basin: an active intra-continental basin. Tectonophysics 36, 197206.

G. Conrad , J.-R. Lappartient , (1991). The appearance of Cardium fauna and foraminifers in the great lakes of the early quaternary period in the Algerian central Sahara desert. Journal of African Earth Sciences 12, 375382.

B. Damnati , (2000). Holocene lake record in the Northern Hemisphere of Africa. Journal of African Earth Sciences 31, 253262.

P. deMenocal , J. Ortiz , T. Guilderson , J. Adkins , M. Sarnthein , L. Baker , M. Yarusinsky , (2000). Abrupt onset and termination of the African Humid Period: rapid climate responses to gradual insolation forcing. Quaternary Science Reviews 19, 347361.

N. Drake , Ch Bristow , (2006). Shorelines in the Sahara: geomorphological evidence for an enhanced Monsoon from palaeolake Megachad. The Holocene 16, 901911.

Ph. Duringer , M. Schuster , J.F. Genise , M. Brunet , P. Vignaud , (2007). New trace fossils of termites, nests and galleries, from the Chad Basin (upper Miocene and Pliocene). Palaeogeography, Palaeoclimatology, Palaeoecology 251, 323353.

S. Engelstaedter , I. Tegen , R. Washington , (2006). North African dust emissions and transport. Earth Science Reviews 79, 73100.

C. Estournel , V. Zervakis , P. Marsaleix , A. Papadopoulos , F. Auclair , L. Perivoliotis , E. Tragou , (2005). Dense water formation and cascading in the Gulf of Thermaikos (North Aegean) from observations and modelling. Continental Shelf Research 25, 23662386.10.1016/j.csr.2005.08.014.

F. Gasse , (2000). Hydrological changes in the African tropics since the Last Glacial Maximum. Quaternary Science Reviews 19, 189211.

J.-F. Ghienne , M. Schuster , A. Bernard , Ph. Duringer , M. Brunet , (2002). The Holocene giant Lake Chad revealed by Digital Elevation Models. Quaternary International 87, 8185.

E. Ghoneim , F. El-Baz , (2007). DEM-optical-radar data integration for palaeohydrological mapping in the northern Darfur, Sudan: implication for groundwater exploration. International Journal of Remote Sensing. 28, 50015018.

R. Guiraud , J.C. Maurin , (1992). Early Cretaceous rifts of Western and Central Africa: an overview. Tectonophysics 213, 153168.

M. Gumnior , F. Preusser , (2007). Late Quaternary river development in the southwest Chad Basin: OSL dating of sediment from the Komadugu palaeofloodplain (northeast Nigeria). Journal of Quaternary Sciences 22, 709719.

R.W. Hartley , P.A. Allen , (1994). Interior cratonic basins of Africa: relation to continental break-up and role of mantle convection. Basin Research 6, 95113.

Ph. Hoelzmann , B. Keding , H. Berke , S. Kroepelin , H.-J. Kruse , (2001). Environmental change and archaeology: lake evolution and human occupation in the eastern Sahara during the Holocene. Palaeogeography, Palaeoclimatology, Palaeoecology 169, 193217.

M. Leblanc , C. Leduc , F. Stagnitti , P.J. van Oevelen , C. Jones , L.A. Mofor , M. Razack , G. Favreau , (2006). Evidence for Megalake Chad, north-central Africa, during the late Quaternary from satellite data. Palaeogeography, Palaeoclimatology, Palaeoecology 230, 230242.

A.-M. Lézine , J.-Cl. Duplessy , J.-P. Cazet , (2005). West African Monsoon variability during the last deglaciation and the Holocene: evidence from fresh water algae, pollen and isotope data from core KW31, Gulf of Guinea. Palaeogeography, Palaeoclimatology, Palaeoecology. 219, 225237.

F. Krist Jr. , R.J. Schaetzl , (2001). Palaeowind (11,000 BP) directions derived from lake spits in northern Michigan. Geomorphology 38, 118.

I. Kusnir , H.A. Moutaye , (1997). Ressources min"rales du Tchad : une revue. Journal of African Earth Sciences 24, 549562.

J. Maley , (1977). Palaeoclimates of Central Sahara during the early Holocene. Nature 269, 573577.

P. Marsaleix , F. Auclair , J.W. Floor , M.J. Herrmann , C. Estournel , I. Pairaud , C. Ulses , (2008). Energy conservation issues in sigma-coordinate free-surface ocean models. Ocean Modelling 20, 6189.10.1016/j.ocemod.2007.07.005.

G. Mellor , (2003). The three-dimensional current and surface wave equations. Journal of Physical Oceanography 33, 19781989.

H.J. Pachur , F. Rottinger , (1997). Evidence for large extended palaeolake in the eastern Sahara as revealed by spaceborne radar lab images. Remote Sensing of Environment 61, 437.

H.J. Pachur , P. Hoelzmann , (2000). Late Quaternary palaeoecology and palaeoclimates of the eastern Sahara. Journal of African Earth Sciences 30, 929939.

B. Rabus , M. Eineder , A. Roth , A. Bamler , (2003). The shuttle radar topography mission a new class of digital elevation models acquired by spaceborne radar. ISPRS Journal of Photogrammetry and Remote Sensing 57, 241262.

A.F. Shchepetkin , J.C. Mc Williams , (2005). The regional oceanic modeling system (roms): A split-explicit, free surface, topography-following-coordinate oceanic model. Ocean Modelling 9, 347404.

M. Schuster , Ph. Duringer , J.-F. Ghienne , P. Vignaud , A. Beauvilain , H.T. Mackaye , M. Brunet , (2003). Coastal conglomerate around the Hadjer el Khamis inselbergs (western Chad, Central Africa): new evidence for Lake Mega-Chad episodes. Earth Surface Processes and Landforms 28, 10591069.

M. Schuster , C. Roquin , M. Brunet , Ph. Duringer , M. Fontugne , H.T. Mackaye , P. Vignaud , J.-F. Ghienne , (2005). Highlighting Holocene Lake Mega-Chad paleoshorelines from space. Quaternary Science Reviews 24, 18211827.

P. Sepulchre , M. Schuster , G. Ramstein , G. Krinner , J.-F. Girard , F. Fluteau , P. Vignaud , M. Brunet , (2008). Simulating the Holocene Lake Mega Chad with an AGCM coupled with a lake model: a preliminary approach. Global and Planetary Change 61, 4148.

C. Ulses , C. Grenz , P. Marsaleix , E. Schaaff , C. Estournel , S. Meul" , C. Pinazo , (2005). Circulation in a semi enclosed bay under the influence of strong fresh water input. Journal of Marine Systems 56, 113132.10.1016/j.jmarsys.2005.02.001.

C. Ulses , C. Estournel , P. Puig , X. Durrieu de Madron , P. Marsaleix , (2008). Dense shelf water cascading in the north-western Mediterranean during the cold winter 2005. Quantification of the export through the Gulf of Lion and the Catalan margin. Geophysical Research Letters 35, L07610 10.1029/2008GL033257.

P. Vignaud , Ph. Duringer , H.T. Mackaye , A. Likius , C. Blondel , J.-R. Boisserie , L. de Bonis , V. Eisenmann , M. Etienne , D. Geraads , F. Guy , Th. Lehmann , F. Lihoreau , N. Lopez-Martinez , C. Mourer-Chauvir" , O. Otero , J.-Cl. Rage , M. Schuster , L. Viriot , A. Zazzo , M. Brunet , (2002). Geology and palaeontology of the Upper Miocene Toros-Menalla hominid locality, Chad. Nature 418, 152155.

P. Wessel , W.H.F. Smith , (1998). New, improved version of the Generic Mapping Tools Released. EOS Trans, ed. American Geophysical Union 79, 579.

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Quaternary Research
  • ISSN: 0033-5894
  • EISSN: 1096-0287
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