Biu Plateau

thumb|upright=1.3|Major geological features near Cameroon line

The '''Biu Plateau''' is a highland area in Northeastern Nigeria containing many recently extinct volcanoes. It covers about {{Convert|5200|km2|mi2|abbr=on}} and has an average elevation of {{Convert|700|m|ft|abbr=on}}.<ref name=Britannica/> The plateau lies between the Upper Benue Basin to the south and the Chad Basin to the north. High points are Wade Hill at {{Convert|775|m|ft|abbr=on}} above sea level and Wiga Hill, at well over {{Convert|800|m|ft|abbr=on}}.<ref name=OLN/> The plateau is the source of many tributaries of the Gongola River, which have cut deep gorges. To the north the plateau slopes gently to the Bauchi plains and the Chad Basin.<ref name=Britannica/>

There is evidence of early volcanic activity in the area during the Cretaceous, which ended about 66 million years ago.<ref>{{cite book|url=https://books.google.com/books?id=oOMNAAAAQAAJ&pg=PA285|page=285|title=West Africa, Volume 25, Part 1|publisher=Taylor & Francis|year=1971}}</ref> However, the plateau was built around the end of the Miocene, and the bulk of the rocks are Pliocene basalts that have erupted from small vents or fissures, and then spread in a thin layer over wide areas. Activity resumed in the Quaternary 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.<ref name=George2009/> There are a number of well-preserved volcanic cones rising above the Plateau along a NNW-SSE axis in the Miringa volcanic zone.<ref name=OLN/>

Some geologists consider that the volcanic activity in the Biu Plateau is associated with the activity in the Cameroon line to the south.<ref name=Rankenburg2004>{{cite journal |title=The Role of Continental Crust and Lithospheric Mantle in the Genesis of Cameroon Volcanic Line Lavas: Constraints from Isotopic Variations in Lavas and Megacrysts from the Biu and Jos Plateaux |author=K. RANKENBURG, J. C. LASSITER and G. BREY |journal=Journal of Petrology |volume=46| issue = 1 |pages=169–190 |year=2004 |doi=10.1093/petrology/egh067|doi-access=free }}</ref>

==See also== *Biu, Nigeria *Biu Emirate

==References== {{reflist|1|refs= <ref name=Britannica>{{cite encyclopedia |url=http://www.britannica.com/EBchecked/topic/67285/Biu-Plateau |title=Biu Plateau |encyclopedia=Encyclopædia Britannica |accessdate=2011-02-02}}</ref> <ref name=George2009>{{cite book |url=https://books.google.com/books?id=U1VBp7aItooC&pg=PA50 |page=50 |title=Geology and Mineral Resources of Nigeria |author=Obaje Nuhu George, Nuhu George Obaje |publisher=Springer |year=2009 |isbn=978-3-540-92684-9}}</ref> <ref name=OLN>{{cite web |url=http://www.onlinenigeria.com/links/LinksReadPrint.asp?blurb=219 |publisher=Online Nigeria |title=Borno: Physical Setting |accessdate=2011-02-02}}</ref> }}

==External links== *{{cite gvp|name=Biu Plateau|vn=224050|access-date=2021-06-24}}

Category:Geology of Nigeria Category:Lava plateaus Category:Volcanoes of Nigeria