The Biu Plateau is a highland area in Northeastern

Nigeria Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, ...

containing many recently extinct

volcano A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most oft ...

es. It covers about and has an average elevation of . The plateau lies between the Upper Benue Basin to the south and the

Chad Basin The Chad Basin is the largest endorheic basin in Africa, centered approximately on Lake Chad. It has no outlet to the sea and contains large areas of semi-arid desert and savanna. The drainage basin is approximately coterminous with the sedimenta ...

to the north. High points are Wade Hill at above sea level and Wiga Hill, at well over . The plateau is the source of many tributaries of the

Gongola River The Gongola River is in northeastern Nigeria, the principal tributary of the Benue River. The upper course of the river as well as most of its tributaries are seasonal streams, but fill rapidly in August and September. The Gongola rises on the e ...

, which have cut deep gorges. To the north the plateau slopes gently to the

Bauchi Bauchi (Fula: ''Leydi Bauchi'' 𞤤𞤫𞤴𞤣𞤭 𞤦𞤢𞤵𞤷𞥅𞤭) is a States of Nigeria, state in the North East (Nigeria), North-East geopolitical zone of Nigeria. It is bordered by Jigawa State, Jigawa to the north, Yobe State, Y ...

plains and the Chad Basin. There is evidence of early volcanic activity in the area during the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

, which ended about 66 million years ago. However, the plateau was built around the end of the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

, and the bulk of the rocks are

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58basalt Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial ...

s that have erupted from small vents or fissures, and then spread in a thin layer over wide areas. Activity resumed in the

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS), as well as the current and most recent of the twelve periods of the ...

with thin flows of lava issuing from small cinder cones and filling the valleys. Most of the basalts date between 7 and 2 million years ago, but some are less than a million years old. The plateau includes many small pyroclastic cones caused by explosions when water penetrated downward and came into contact with fresh lava. There are a number of well-preserved volcanic cones rising above the Plateau along a NNW-SSE axis in the Miringa volcanic zone. Some geologists consider that the volcanic activity in the Biu Plateau is associated with the activity in the

Cameroon line The Cameroon line (, , ) is a long chain of volcanoes that includes islands in the Gulf of Guinea and mountains on the African mainland, from Mount Cameroon on the coast towards Lake Chad on the northeast. They form a natural border between ea ...

to the south.

References

External links

* {{Coord, 10, 40, 42, N, 12, 0, 19, E, display=title Geology of Nigeria Lava plateaus Volcanoes of Nigeria

See also

References

External links