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African basins
Joumal of African Earth Sciences, Vol. 29, No, 3, pp. 6 2 7 - 6 2 8 , 1999
Pergamon
PII:S0899-5362(99)00119-0
© 1999 Elsevier Science L t d A , rights r e s . . . . d. Printed in Great Britain 0899-5362199 $- see front matter
African Basins Edited by R.C. Selley
Sedimentary Basins of the World, vol. 3, Series Editor K.J. Hs~. Elsevier Science (1997). ISBN 0-444-82571-1 (Vol. 3) (hbk). 394p. Price NLG 450.00/US$281.25
This book contains 13 papers by various authors, arranged into three parts: Northern Africa; Central Africa; and Southern Africa. The scientific papers are preceded by an Introduction to the Series written by the Series Editor and an Introduction and Acknowledgements by the Volume Editor, and are followed by Part 4, Summary by the Series Editor. Three indices: Author Index, Geographic, Tectonic and Stratigraphic Index, and Minerals, Petroleum, Rocks and Fossils Index, are provided. Much interesting material is presented. The papers on Rift Basins of Sudan by R.B. Salama, Coastal Basins of Somalia, Kenya and Tanzania by E.I. Mbede and A. Dualeh, and the Niger River Delta Basin by T.J.A. Reijers et aL, are especially valuable, synthesising compilations of data published in many previous papers, some of them hard to obtain. Part three of the book contains excellent regional syntheses of the Ovambo Basin and the underlying Neoproterozoic Damara Supergroup by R. McG. Miller, the Foreland Karoo Basin of South Africa by M.R. Johnson et aL, and the Late Mesozoic Sedimentary Basins off the south coast of South Africa by I.K. McMillan et al. The Ovambo Basin contains three sequences: the Neoproterozoic Damara Supergroup, deposited on the passive margin of the Congo Craton, the Late Palaeozoic-Mesozoic Karoo Supergroup, deposited in an intracontinental basin of Pangaea, and the Tertiary to Recent Kalahari Supergroup. The Foreland Karoo Basin of South Africa is located north of the Cape fold and thrust belt, in which the 8 km thick Ordovician to Early Carboniferous group was deposited in a passive margin of the Kalahari Craton. The Karoo Basin fill is up to 10 km thick and ranges in age from latest Carboniferous to Jurassic. The intrusion of dolerite sills and outpouring of basaltic lavas signalled the onset of extension that led to Gondwana break-up. The summary of mineral resources of the Karoo Basin is especially interesting.
The Late Mesozoic Sedimentary Basins off the south coast of South Africa are associated with a portion of continental margin of Africa dominated by dextral movement along the Agulhas-Falklands Fracture Zone. The history of these basins began with Late Jurassic rifting and half-graben formation, followed by a Late Valanginian early drift sequence that contains oxygen deficient facies in the Hauterivian-Early Aptian stratigraphical interval. The orientation of these basins is related to shearing along the Agulhas-Falklands Fracture Zone. Late drift sedimentation (Late Aptian to Maastrichtian) resulted in the formation of the Outeniqua Basin, with a transverse orientation to the pre-existing rift basins. The region has produced gas and condensate since 1992. Other papers contain rudimentary descriptions of the stratigraphy, facies and large-scale structure of selected basins of northwest Africa: the Sirte Basin and the sedimentary basins of Egypt, the lullemmeden Basin of Niger, classified as belonging in Central Africa, the passive margin basins of equatorial and southern Africa from the Benue Trough southward to the Orange River Basin (in a paper entitled: The West African Coastal Basins, sic!), and the East Africa Rift Basins. I would expect the very high price of the book to be supported by the highest subject matter and technical editorial standard. Regrettably this is not the case. With regard to the latter, there are occasional typographical errors, and geographic names are used inconsistently, e.g. 'Murzuk' and 'Moursouk'. These are minor but vexing deficiencies. Chapters 1 and 2 contain verbatim the same paragraphs - a rather unusual feature in a book priced at US$281.25. Even more surprising are the entries 'condensate' and 'condensate field' in the Geographic, Tectonic and Stratigraphic Index, and adjective entries (e.g. 'glauconitic') and stratigraphical names (e.g. 'Berriasian', 'Hauterivian' and 'Kimmeridgian') in the Minerals, Petroleum, Rocks and Fossils Index.
Journal of African Earth Sciences 627
BOOK REVIEW Although some parts of the book are excellent, the reader is likely to be disappointed by the whole volume. The book title is misleading. Only selected sedimentary basins of Africa are described, and the reasons for selection are rather hard to figure out. The majority of the basins described are of Phanerozoic age, but if this was a criterion for selection why are half of the Tindouf Basin, the Taoudeni Basin of West Africa, the Volta Basin, the Cuvette Centrale of the Congo (formerly Zaire) and the Karoo Basins of Zambia not included? Moreover, Africa contains a large number of older Arch~ean and Proterozoic sedimentary basins, many of them unique in the history of the continental crust and/or hosting major mineral resources, to name just the Witwatersrand, Waterberg, Mporokoso, Francevillian, Katangan, Kundelungu and Nama Basins. I would expect a book on African Basins in the series 'Sedimentary Basins of the World' to contain a comprehensive set of papers on all important basins of the continent. The book is generously illustrated. Some papers, especially in Part three, contain clear, professional-
looking figures. Others, especially in Part one, have figures partly hand-drafted and aesthetically unpleasant. The Series Editor states in the Summary (Part four of the book) that the volumes of the series Sedimentary Basins of the World "willnot be philately albums; they will not be collections of random observation. There will be pieces of mosaic to be pieced together for a unifying theory of global tectonics." Surprisingly, in discussions of the generalities of Palaeozoic and Mesozoic stratigraphical sequences of northern Africa, neither Gondwana nor Pang~ea are mentioned, and these terms do not appear in the index. Yet these supercontinents provide the global tectonic background for the tectonics and depositional processes of the sedimentary basins of Africa. Gondwana is discussed in this context only in papers constituting Part three of the book. It is difficult to avoid the conclusion that the book 'African Basins' is in fact a 'philately album', filled with a haphazard collection of stamps from sad envelopes of an old packet of love letters given away to the collector by a spinster aunt. R. Unrug Wright State University Dayton, OH USA
628 Journal of African Earth Sciences
Pergamon
PII:S0899-5362(99)00119-0
© 1999 Elsevier Science L t d A , rights r e s . . . . d. Printed in Great Britain 0899-5362199 $- see front matter
African Basins Edited by R.C. Selley
Sedimentary Basins of the World, vol. 3, Series Editor K.J. Hs~. Elsevier Science (1997). ISBN 0-444-82571-1 (Vol. 3) (hbk). 394p. Price NLG 450.00/US$281.25
This book contains 13 papers by various authors, arranged into three parts: Northern Africa; Central Africa; and Southern Africa. The scientific papers are preceded by an Introduction to the Series written by the Series Editor and an Introduction and Acknowledgements by the Volume Editor, and are followed by Part 4, Summary by the Series Editor. Three indices: Author Index, Geographic, Tectonic and Stratigraphic Index, and Minerals, Petroleum, Rocks and Fossils Index, are provided. Much interesting material is presented. The papers on Rift Basins of Sudan by R.B. Salama, Coastal Basins of Somalia, Kenya and Tanzania by E.I. Mbede and A. Dualeh, and the Niger River Delta Basin by T.J.A. Reijers et aL, are especially valuable, synthesising compilations of data published in many previous papers, some of them hard to obtain. Part three of the book contains excellent regional syntheses of the Ovambo Basin and the underlying Neoproterozoic Damara Supergroup by R. McG. Miller, the Foreland Karoo Basin of South Africa by M.R. Johnson et aL, and the Late Mesozoic Sedimentary Basins off the south coast of South Africa by I.K. McMillan et al. The Ovambo Basin contains three sequences: the Neoproterozoic Damara Supergroup, deposited on the passive margin of the Congo Craton, the Late Palaeozoic-Mesozoic Karoo Supergroup, deposited in an intracontinental basin of Pangaea, and the Tertiary to Recent Kalahari Supergroup. The Foreland Karoo Basin of South Africa is located north of the Cape fold and thrust belt, in which the 8 km thick Ordovician to Early Carboniferous group was deposited in a passive margin of the Kalahari Craton. The Karoo Basin fill is up to 10 km thick and ranges in age from latest Carboniferous to Jurassic. The intrusion of dolerite sills and outpouring of basaltic lavas signalled the onset of extension that led to Gondwana break-up. The summary of mineral resources of the Karoo Basin is especially interesting.
The Late Mesozoic Sedimentary Basins off the south coast of South Africa are associated with a portion of continental margin of Africa dominated by dextral movement along the Agulhas-Falklands Fracture Zone. The history of these basins began with Late Jurassic rifting and half-graben formation, followed by a Late Valanginian early drift sequence that contains oxygen deficient facies in the Hauterivian-Early Aptian stratigraphical interval. The orientation of these basins is related to shearing along the Agulhas-Falklands Fracture Zone. Late drift sedimentation (Late Aptian to Maastrichtian) resulted in the formation of the Outeniqua Basin, with a transverse orientation to the pre-existing rift basins. The region has produced gas and condensate since 1992. Other papers contain rudimentary descriptions of the stratigraphy, facies and large-scale structure of selected basins of northwest Africa: the Sirte Basin and the sedimentary basins of Egypt, the lullemmeden Basin of Niger, classified as belonging in Central Africa, the passive margin basins of equatorial and southern Africa from the Benue Trough southward to the Orange River Basin (in a paper entitled: The West African Coastal Basins, sic!), and the East Africa Rift Basins. I would expect the very high price of the book to be supported by the highest subject matter and technical editorial standard. Regrettably this is not the case. With regard to the latter, there are occasional typographical errors, and geographic names are used inconsistently, e.g. 'Murzuk' and 'Moursouk'. These are minor but vexing deficiencies. Chapters 1 and 2 contain verbatim the same paragraphs - a rather unusual feature in a book priced at US$281.25. Even more surprising are the entries 'condensate' and 'condensate field' in the Geographic, Tectonic and Stratigraphic Index, and adjective entries (e.g. 'glauconitic') and stratigraphical names (e.g. 'Berriasian', 'Hauterivian' and 'Kimmeridgian') in the Minerals, Petroleum, Rocks and Fossils Index.
Journal of African Earth Sciences 627
BOOK REVIEW Although some parts of the book are excellent, the reader is likely to be disappointed by the whole volume. The book title is misleading. Only selected sedimentary basins of Africa are described, and the reasons for selection are rather hard to figure out. The majority of the basins described are of Phanerozoic age, but if this was a criterion for selection why are half of the Tindouf Basin, the Taoudeni Basin of West Africa, the Volta Basin, the Cuvette Centrale of the Congo (formerly Zaire) and the Karoo Basins of Zambia not included? Moreover, Africa contains a large number of older Arch~ean and Proterozoic sedimentary basins, many of them unique in the history of the continental crust and/or hosting major mineral resources, to name just the Witwatersrand, Waterberg, Mporokoso, Francevillian, Katangan, Kundelungu and Nama Basins. I would expect a book on African Basins in the series 'Sedimentary Basins of the World' to contain a comprehensive set of papers on all important basins of the continent. The book is generously illustrated. Some papers, especially in Part three, contain clear, professional-
looking figures. Others, especially in Part one, have figures partly hand-drafted and aesthetically unpleasant. The Series Editor states in the Summary (Part four of the book) that the volumes of the series Sedimentary Basins of the World "willnot be philately albums; they will not be collections of random observation. There will be pieces of mosaic to be pieced together for a unifying theory of global tectonics." Surprisingly, in discussions of the generalities of Palaeozoic and Mesozoic stratigraphical sequences of northern Africa, neither Gondwana nor Pang~ea are mentioned, and these terms do not appear in the index. Yet these supercontinents provide the global tectonic background for the tectonics and depositional processes of the sedimentary basins of Africa. Gondwana is discussed in this context only in papers constituting Part three of the book. It is difficult to avoid the conclusion that the book 'African Basins' is in fact a 'philately album', filled with a haphazard collection of stamps from sad envelopes of an old packet of love letters given away to the collector by a spinster aunt. R. Unrug Wright State University Dayton, OH USA
628 Journal of African Earth Sciences