The Iullemmeden Basin (

Berber language The Berber languages, also known as the Amazigh languages or Tamazight,, ber, label=Tuareg Tifinagh, ⵜⵎⵣⵗⵜ, ) are a branch of the Afroasiatic language family. They comprise a group of closely related languages spoken by Berber commun ...

: Iwellemmedden) is a major sub-Saharan inland basin in

West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Mali, Maurit ...

, extending about north to south and east to west. It covers western

Niger ) , official_languages = , languages_type = National languagesAlgeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , relig ...

Mali Mali (; ), officially the Republic of Mali,, , ff, 𞤈𞤫𞤲𞥆𞤣𞤢𞥄𞤲𞤣𞤭 𞤃𞤢𞥄𞤤𞤭, Renndaandi Maali, italics=no, ar, جمهورية مالي, Jumhūriyyāt Mālī is a landlocked country in West Africa. Mali ...

and

Nigeria Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf o ...

. It is named after the Iullemmeden, a federation of

Tuareg people The Tuareg people (; also spelled Twareg or Touareg; endonym: ''Imuhaɣ/Imušaɣ/Imašeɣăn/Imajeɣăn'') are a large Berber ethnic group that principally inhabit the Sahara in a vast area stretching from far southwestern Libya to southern Al ...

who live in the central region of Niger. Its geographic range is largely coincident with the

Azawagh The Azawagh (alias ''Azaouagh'' or ''Azawak'') is a dry structural basin, basin covering what is today the northwestern Niger, as well as parts of northeastern Mali and southern Algeria. The Azawagh is mainly made up of Sahelian and Saharan f ...

region.Paris, 1995

Description

The area of the Iullemmeden Basin seems to have started to subside in Permo-Triassic times, and to have experienced gradual downwarping during the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

Paleogene The Paleogene ( ; British English, also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period, geologic period and system that spans 43 million years from the end of the Cretaceous Period million yea ...

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 The Aïr Mountains or Aïr Massif ( tmh, Ayăr; Hausa: Eastern ''Azbin'', Western ''Abzin'') is a triangular massif, located in northern Niger, within the Sahara. Part of the West Saharan montane xeric woodlands ecoregion, they r ...

Stratigraphy

The sediments from

Cambrian The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

times are thick, with alternating layers formed when the basin was undersea and above sea level. Potentially valuable minerals include

uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

and

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...

ores and

coal Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dea ...

and

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...

deposits. Niger is one of the world's largest producers of

Formations of the Iullemmeden Basin

* Gwandu Formation * Kalambaina Formation * Wurno Formation * Taloka Formation * Dukamaje Formation * Igdaman Group * Majias Group ** Farin Doutchi Formation **

In Beceten Formation The In Beceten Formation, also Beceten or Ibecten is a Coniacian to Santonian geologic formation in the Iullemmeden Basin of Niger. Dinosaur remains are among the fossils that have been recovered from the formation, although none have yet been re ...

* Zoo Baba Formation * Alanlara Formation * Tegama Group **

Farak Formation The Farak Formation is a geological formation in Niger, central Africa. Its strata date back to the Early Cenomanian. Dinosaur remains are among the fossils that have been recovered from the formation.Weishampel, David B; et al. (2004). "Dinosau ...

Echkar Formation The Echkar Formation is a geological formation comprising sandstones and claystones in the Agadez Region of Niger, central Africa. Description Its strata date back to the Late Albian to Late Cretaceous ( Cenomanian stages, about 100-95 milli ...

Elrhaz Formation The Elrhaz Formation is a geological formation in Niger, central Africa. Its strata date back to the Early Cretaceous, about 125 to 112 million years ago. Dinosaur remains are among the fossils that have been recovered from the formation, alongsi ...

** Tazolé Formation * Ilrhazer Group ** Tiourarén Formation ** Irhazer Shale * Téfidet Group ** Tagrezou Sandstone * Agadez GroupYoung et al., 2017, p.379 ** Assaouas Formation ** Tchirezrine Formation ** Teloua Formation * Izégouandane Group ** Moradi Formation ** Tamamait Formation ** Tejia Formation ** Izégouandane Formation

References

Bibliography

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Description

Stratigraphy

Formations of the Iullemmeden Basin

See also

References

Bibliography

Further reading