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J. B. Wright
Earth Sciences
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Article
Book reviews
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Article
Book reviews
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Book
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Chapter
Introduction to sedimentary basins
An older and a younger group of sedimentary basins can be distinguished in West Africa, and the basins are of two main kinds. Intracontinental basins are relatively broad and shallow with a thin sediment fill,...
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Introduction to anorogenic magmatism
Anorogenic magmatism in West Africa began in the Palaeozoic, soon after the Pan African event, but most of it occurred from Mesozoic times onwards. A number of petrographic provinces can be identified.
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The geological setting
This chapter first outlines the main geological and physio-graphical elements of Africa. A brief review of the major subdivisions of geological time provides a framework within which the boundaries of cratonic...
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Introduction: earthquakes, volcanoes and meteorites
The Quaternary should not be viewed in isolation but as a link with the more distant geological past. In many places, the present cycle of weathering and erosion began long ago, and is responsible for some imp...
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The Pan African of West Africa — the western domain
In the western Pan African domain, the Rokelides encompass a single low-grade ensialic supracrustal belt on the western margin of the Archaean cratonic nucleus, which suffered slight reactivation during the Pa...
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The Precambrian of West Africa — synthesis and review
The similarities between the three major age provinces in the West African Precambrian are more striking than the differences, though the rocks span more than 2000 Ma of geological time.As there is good eviden...
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Mesozoic to Tertiary basins — inland basins
After the seas retreated from Africa at the end of the Carboniferous there was a long period of continental erosion and sedimentation. The products of this phase did not begin to accumulate to any significant ...
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Economic potential of the younger sedimentary basins
The Mesozoic-Tertiary basins of West Africa are of great economic importance to the countries in which they occur, mainly because of the energy resources they contain. These are dominated by petroleum, but inc...
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The Permo-Triassic dolerites and carbonatites
The Permo-Triassic dolerites intrude rocks of the West African craton and the overlying Palaeozoic sediments. They are dominated by dykes and sills. The Freetown igneous complex is a layered gabbro-anorthosite...
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Cretaceous and Cenozoic magmatism
Kimberlite dykes and pipes found in many parts of the West African craton are probably mainly of Cretaceous age, but some may be much older. Several are diamondiferous. A suspected kimberlite in Nigeria is pro...
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The Proterozoic of West Africa
This chapter covers the eastern portion of the West African craton, dominated by Birimian supracrustals that were deformed and metamorphosed in the Eburnian thermo-tectonic event about 2 billion years ago. The...
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Geomorphology, Quaternary deposits and water resources
Much of the southern part of West Africa is relatively low lying and of low relief. It includes the drought-prone Sahe-lian belt south of the Sahara. The drainage pattern is naturally westward and southward to...
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The Pan African of West Africa — the eastern domain
East of the craton there are many low-grade supracrustal belts mainly occupying a broad elongate NNE-SSWzone in the western half of Nigeria. They are dominated by clastic metasediments, but basic and ultrabasi...
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The Benue Trough and coastal basins
The Benue Trough is an elongate rifted depression in which the sediments reach well over 5000 m thickness in places and have been strongly folded, probably by later adjustments along faults in the underlying b...
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The Younger Granites
The Younger Granite ring complexes of West Africa extend from Air to Cameroun and range in age from Palaeozoic to Tertiary. They are dominated by granites and are emplaced in Pan African basement rocks, on ‘sw...
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The Archaean of West Africa
The nucleus of the West African craton is characterised by the typical Archaean granite-greenstone association in which the ‘granite’ component (basement + intrusive granites) is dominant in areal terms. Metav...
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Infracambrian to Lower Palaeozoic basins
The Volta and Taoudeni Basins have similar successions, though they are given different names in different places. Sparse radiometric data place the onset of sedimentation at around 1000 Ma ago, and products o...
