View source for Iullemmeden Basin

{{Infobox sedimentary basin
| name                   = Iullemmeden Basin
| other_name             = 
| named_for              = [[Iullemmeden]]
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| pushpin_map            = Africa
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| pushpin_relief         = 1
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| map_image              = Iullemmeden Basin.svg
| map_size               = 
| map_alt                = 
| map_caption            = Location of the Iullemmeden Basin
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| coordinates            = {{coord|17.9|N|5.6|E|display=inline,title}}
| location               = [[Africa]]
| region                 = [[Azawagh]]
| country                = {{ALG}}<br />{{BEN}}<br />{{MLI}}<br />{{NIG}}<br />{{NGA}}
| state                  = 
| cities                 = 
| onoffshore             = Onshore
| boundaries             = [[Aïr Mountains]] (NE)
| partof                 = 
| seas                   = 
| rivers                 = [[Niger River]]
| lakes                  = 
| area                   = {{convert|1000|x|800|km|mi|abbr=on}}
| basin_type             = [[Intercratonic basin]]
| plate                  = [[African Plate|African]]
| orogeny                = [[Pan-African orogeny|Pan-African]]
| age                    = [[Permian-Triassic extinction|Permo-Triassic]]-[[Pleistocene]]
| stratigraphy           = [[Iullemmeden Basin#Stratigraphy|Stratigraphy]]
| fields                 = 
| faults                 = 
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}}
[[File:West African Basins.svg|thumb|300px|West African basins]]
The '''Iullemmeden Basin''' ([[Berber language]]: '''Iwellemmedden''') is a major sub-Saharan inland basin in [[West Africa]], extending about {{convert|1000|km|mi}} north to south and {{convert|800|km|mi}} east to west. It covers western [[Niger]] and parts of [[Algeria]], [[Mali]] and [[Nigeria]]. It is named after the [[Iullemmeden]], a federation of [[Tuareg people]] who live in the central region of Niger.<ref name=Selley1997/> Its geographic range is largely coincident with the [[Azawagh]] region.<ref>Paris, 1995</ref>

== Description ==
The area of the Iullemmeden Basin seems to have started to subside in [[Permian-Triassic extinction|Permo-Triassic]] times, and to have experienced gradual downwarping during the [[Late Cretaceous]] to [[Paleogene]] times, while steadily filling with sediment. Two prominent fault trends run NNE-SSW through the center of the basin, while WSW-ENE faults trends are found in the northeast of the basin near the [[Aïr Mountains]].<ref name=Selley1997/>

== Stratigraphy ==
The sediments from [[Cambrian]] to [[Pleistocene]] times are {{convert|1500|to|2000|m|ft}} thick, with alternating layers formed when the basin was undersea and above sea level. Potentially valuable minerals include [[uranium]] and [[copper]] ores and [[coal]] and [[salt]] deposits. Niger is one of the world's largest producers of [[uranium]].<ref name=NWT/>

=== Formations of the Iullemmeden Basin ===
{{see also|List of fossiliferous stratigraphic units in Niger}}
* [[Gwandu Formation]]
* [[Kalambaina Formation]]
* [[Wurno Formation]]
* [[Taloka Formation]]
* [[Dukamaje Formation]]
* [[Igdaman Group]]
* [[Majias Group]]
** [[Farin Doutchi Formation]]
** [[In Beceten Formation]]
* [[Zoo Baba Formation]]
* [[Alanlara Formation]]
* [[Tegama Group]]
** [[Farak Formation]]
** [[Echkar Formation]]
** [[Elrhaz Formation]]
** [[Tazolé Formation]]
* [[Ilrhazer Group]]
** [[Tiourarén Formation]]
** [[Irhazer Shale]]
* [[Téfidet Group]]	
** [[Tagrezou Sandstone]]
* [[Agadez Group]]<ref name=Young2017_p379>Young et al., 2017, p.379</ref>
** [[Assaouas Formation]]
** [[Tchirezrine Formation]]
** [[Teloua Formation]]
* [[Izégouandane Group]]<ref name=Young2017_p379/>
** [[Moradi Formation]]
** [[Tamamait Formation]]
** [[Tejia Formation]]
** [[Izégouandane Formation]]

== See also ==
{{Portal|Geology}}
*[[Chad Basin]]
*[[Niger Delta Basin]]
*[[Taoudeni Basin]]

== References ==
{{reflist|1|refs=
<ref name=NWT>{{cite web
 |url         = http://www.nwturanium.com/i/pdf/Uranium-Niger-Investor.pdf
 |title       = URANIUM GEOLOGY: NIGER, WEST AFRICA
 |publisher   = NWT Uranium Corporation
 |access-date  = 2010-12-18
 |url-status=dead
 |archive-url  = https://web.archive.org/web/20110714214532/http://www.nwturanium.com/i/pdf/Uranium-Niger-Investor.pdf
 |archive-date = 2011-07-14
}}</ref>
<ref name=Selley1997>{{cite book
 |chapter-url=https://books.google.com/books?id=KaxnNYz2g6EC&pg=PA89
 |page=89ff
 |chapter=The Iullemmeden Basin
 |title=African basins
 |author=Richard C. Selley
 |publisher=Elsevier
 |year=1997
 |isbn=0-444-82571-1}}</ref>
}}

=== Bibliography ===
* {{cite news |title=L Bassin de I'Azawagh : peuplements et civilisations, du néolithique à l'arrivée de l'islam |last=Paris |first=François |work=Milieux, sociétés et archéologues |publisher=Karthala |year=1995 |language=fr |url=http://horizon.documentation.ird.fr/exl-doc/pleins_textes/pleins_textes_7/b_fdi_03_04/42071.pdf |page=228 |access-date=3 April 2012}}
* {{citation |last=Young |first=Mark T. |last2=Hastings |first2=Alexander K. |last3=Allain |first3=Ronan |last4=Smith |first4=Thomas J. 
|year=2017 |title=Revision of the enigmatic crocodyliform ''Elosuchus felixi'' de Lapparent de Broin, 2002 from the Lower–Upper Cretaceous boundary of Niger: potential evidence for an early origin of the clade Dyrosauridae |journal=[[Zoological Journal of the Linnean Society]] |volume=179 |pages=377–403}}

== Further reading ==
* {{cite web
 |url=http://www.earthbyte.org/Resources/ICONS/AFR/IullemmedenBasin/AFR.IullemmedenBasin.html
 |title=ICONS atlas: AFR - Iullemmeden Basin
 |work=Earth Byte
 |access-date=2010-12-18}}

{{Major African geological formations|state=collapsed}}

[[Category:Sedimentary basins of Africa]]
[[Category:Landforms of Algeria]]
[[Category:Landforms of Mali]]
[[Category:Landforms of Niger]]
[[Category:Landforms of Nigeria]]
[[Category:Landforms of Benin]]
[[Category:Geology of Algeria]]
[[Category:Geology of Mali]]
[[Category:Geology of Niger]]
[[Category:Geology of Nigeria]]
[[Category:Geology of Benin]]