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Geological Atlas of Africa Thomas Schluter¨

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Geological Atlas of Africa Thomas Schluter¨ Geological Atlas of Africa Thomas Schluter¨ Geological Atlas of Africa With Notes on Stratigraphy, Tectonics, Economic Geology, Geohazards, Geosites and Geoscientific Education of Each Country With contributions by Martin H. Trauth 2nd four-coloured revised and enlarged edition, with 417 figures and a CD-ROM 123 Thomas Schl¨uter UNESCO Nairobi Office Nairobi Kenya [email protected] ISBN: 978-3-540-76324-6 e-ISBN: 978-3-540-76373-4 Library of Congress Control Number: 2008923786 1st Edition 2006 c 2008 Springer-Verlag Berlin Heidelberg This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Typesetting: Camera-ready by E. Sillmann Cover design: WMXDesign, Heidelberg Printed on acid-free paper 987654321 springer.com Acknowledgements Over the last 10 years since the inception of the Digitizing of various printed maps was done by Geological Atlas of Africa Project, I have been fortu- Dirk Spengler (Utrecht), Nadja Insel (Potsdam) and nate to have had support from many individuals and Stephen Mogere (Nairobi). Th e fi nal layout of the institutions in several African, European and North maps and the complete page design was created by American countries. My interest in the compilation Dipl.-Ing. Elisabeth Sillmann (Landau/Pfalz). of geological overview maps of Africa grew out from the conviction of my late supervisor, Walter G. Kühne, I am grateful to Dr. Christian Witschel (Heidelberg) who had taught me that basic understanding of the for the incorporation of this atlas into the Springer geology of an area or region will never happen with- Geosciences Programme. out initial observation of the respective available geo- logical map. It is therefore my hope that by critical evaluation of the here presented maps further scien- I acknowledge the following copyright holders for tifi c work may be successfully carried out. permission to use copyright material: I am indebted to a great number of individuals for BBC Books, assistance in many areas beyond my own discipline photographs on ps 38; 224. of Historical Geology and Palaeontology. Finan- cial support was received from DAAD (German Borntraeger Verlag, Academic Exchange Service), namely Mr. Cay photographs 18; 20; 91. Etzold, Director of the DAAD Offi ce in Nairobi from 2001–2005. My colleagues in the UNESCO Nairobi DuMont Buchverlag, Office, Dr. Paul Vitta, Prof. Joseph Massaquoi, photographs 28; 29. Alice Ochanda, and Dr. Robert Höft (now Toronto) provided an environment that was very innova- Ferdinand Enke Verlag, tive for the creation of the maps and the text of the photographs 2; 4. atlas. Similarly I was encouraged by my colleagues at UNESCO Headquarters in Paris, Drs. Wolfgang Geological Society of South Africa, Eder, Robert Missotten and Margarete Patzak, and photographs on ps 62; 193; 217. at fi eld offi ces in Windhoek, Alex Magarikakis, and Nairobi, Noeline Raondry-Rakotoarisoa. Profs. Justus Perthes Verlag Gotha Britta Schütt (Berlin), Dieter Jäkel (Berlin), Jürgen photographs on ps 20; 24; 52; 188; 232. Wohlenberg (Hannover), Volker Jacobshagen (Berlin), Wolf U. Reimold (Berlin), Martin Strecker Harry N. Abrams, (Potsdam), Eckart Wallbrecher (Graz, Austria), Peter photographs 87; 212, 262. van Straaten (Guelph, Canada), Th eo Davies (Jos, Nigeria), Sospeter Muhongo (Pretoria, South Africa), National Geographic, Henry Kampunzu† (Gaborone, Botswana), Isaac photographs on ps 17; 33. Konfor Njilah (Yaounde, Cameroon), and Manuel Pinto (Porto, Portugal) contributed in many ways Der Spiegel, signifi cantly to the fi nal text and sometimes with photograph on pg 95 left . photographs of various geosites. Dr. Andreas Berger (Potsdam), Wolfgang Zils (Berlin) and Dr. Christa Struik, Werner (Berlin) provided an invaluable mass of photographs on ps 10; 12. information on the geology of East Africa. To Dr. Wolfgang Wramik (Rostock) I am indebted for his Time, contribution on the island of Socotra. frontispiece July 2002. VI Acknowledgements Weidenfeld & Nicholson, Geoscience Press, Inc., photographs on ps 49; 71; 77; 139. photograph on pg 71. World Wild Fund for Nature, Vintage, photographs 24; 27; 46. photograph before pg 59. C. Bertelsmann, Waldemar Kramer, photographs 2; 12; 13. photograph on pg. 111. AGID Report Series Geosciences in Jahrbuch Geologische Bundesanstalt, Vienna, International Development, photograph on pg 35. photographs on ps 208; 210. Welterbe der UNESCO, ADAC-Buch, Bradt Travel Guides Ltd, photograph on ps 33; 67; 76; 77. photographs on ps 3; 7. Nymphenburger, Interlink Publishing Group, photograph on pg 68. photograph on ps 28; 160. Deutscher Kunstverlag München Berlin, Mémoire de la Terre, photographs on ps 52, 130; 137. photographs on ps 66; 71; 94. Every eff ort was made to trace the copyright hold- Philipp von Zabern, ers, but if any of them inadvertently has been over- photograph on pg 100. looked, the necessary arrangements will be made at the fi rst opportunity. Preface Th is atlas is intended primarily for anybody who is in- some background for the arrangement of how the terested in basic geology of Africa. Its originality lies atlas was done. Th e second chapter is devoted to the in the fact that the regional geology of each African history of geological mapping in Africa, necessary nation or territory is reviewed country-wise by maps for a fuller appreciation of why this work in Africa is and text, a view normally not presented in textbooks worth doing. Chapter 3 provides an executive sum- of regional geology. It is my belief, that there has long mary on the stratigraphy and tectonics of Africa as a been a need in universities and geological surveys, whole, i. e. in the context of no political boundaries. both in Africa and in the developed world, for sum- Th e main part of the atlas lies in Chapter 4, where in marizing geological maps and an accompanying basic alphabetical order each African country or territory text utilising the enormous fund of knowledge that is presented by a digitized geological overview map has been accumulated since the beginning of geologi- and an accompanying text on its respective stratig- cal research in Africa in the mid-19th century. I hope raphy, tectonics, economic geology, geohazards and that, in part, the present atlas may satisfy this need. geosites. A short list of relevant references is also add- ed. Th e atlas, essentially devoted to African geology, Th e idea to compile the atlas resulted from my teach- off ers in a condensed way data on all aspects of cur- ing experience at African universities for more than rent geoscientific issues that may in future contribute 20 years, and aft er I had witnessed that my colleagues to the development of this continent. there oft en had no access to geological overview maps, references and literature of other African countries, Nairobi, February 2005 Th omas Schlüter sometimes badly needed for teaching purposes. In western eyes Africa is oft en perceived only as a land of adventurers and explorers, but while Africa is un- deniably diverse and diff erent, it has never been a Preface to the 2nd Edition lost continent – only unfamiliar, underappreciated, misunderstood or forgotten. Anybody who has ever Th e commercial success and many well-aimed reviews gone to Africa has taken a part of it away and left of the fi rst edition of this atlas have led aft er only 2 ½ something behind. Th e results have not been always years since its publication to a new edition, which in good, nor have they always been bad, but they have parts has been modifi ed due to previously unknown all gone into the mix that makes up the African soci- data. Some of the maps are completely new and many ety. Th e atlas is therefore intended to build capabili- photographs of geological sites were added. As the ties and capacities at various places in Africa, so that atlas shall be used preferentially by African geolo- the people there can later continue on their own with gists, I decided to add for each country or territory a what I had begun. paragraph on the current state of art of geoscientifi c education there. Th ese data are based on departmen- Th e atlas is subdivided into four chapters centering on tal websites and were compiled mainly from a report regional geological aspects of each African country or on Geoscience Education in Africa submitted to the territory. Th e first chapter defines the scientific issues Ecological and Earth Science Division in UNESCO’s involved in the preparation of the atlas and provides Headquarter in Paris. 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