Natural Hazards in West and Central Africa

1. Front Matter

   Pages I-2

   PDF

2. Introduction

   1. An introduction to the natural hazards of West and Central Africa

      • S. J. Freeth

      Pages 3-5

3. Earthquakes

   1. The seismicity of West and Central Africa

      • R. M. W. Musson

      Pages 7-11

   2. Fossil plate boundaries in West Africa and their bearing on seismotectonics

      • K. Mosto Onuoha, C. C. Ezeh

      Pages 13-29

   3. The December 22, 1983, earthquake in Guinea, West Africa

      • C. J. Langer, G. A. Bollinger

      Pages 31-36

4. Volcanic Gases

   1. Volcanic gases as a natural hazard

      • S. J. Freeth

      Pages 37-43

   2. Potentially hazardous lakes in West Africa

      • S. J. Freeth

      Pages 45-56

   3. Natural disasters in the oral history of West Cameroon

      • Eugenia Shanklin

      Pages 57-62

   4. The Lake Nyos gas disaster

      • S. J. Freeth

      Pages 63-82

   5. The origin of gases in Lake Nyos, Cameroon

      • Minoru Kusakabe, Yuji Sano

      Pages 83-95

   6. Cyclic gas bursts: are they a ‘usual’ feature of Lake Nyos and other gas-bearing lakes?

      • Klaus Tietze

      Pages 97-107

   7. Seismic monitoring of Lake Nyos, Cameroon

      • A. B. Walker, D. W. Redmayne, C. W. A. Browitt

      Pages 109-136

5. Landslides and Erosion

   1. An appraisal of landslides in southern Nigeria

      • C. O. Okagbue

      Pages 137-147

   2. Gullying in the Idemili River catchment, Anambra State, Nigeria: theory and cure

      • C. S. Nwajide

      Pages 149-162

   3. Expansive soils: the silent hazard in Bauchi State, Nigeria

      • D. M. Orazulike

      Pages 163-174

Attention to the problems posed by natural hazards in West and Central Africa was brought into sharp focus by the deaths of an estimated 1700 people in the valleys to the north of Lake Nyos in 1986. Prior to that the only, well documented, major natural catastrophe was the 1983 earthquake which killed at least 275 people in northwestern Guinea. Though we would not wish to appear to suggest that the 1939 Accra earthquake, which killed 16 people, or the Lake Monoun disaster, which killed 37 people in 1984, were not significant events for the areas concerned. The full horror of the Lake Nyos gas disaster was exacerbated, as far as the outside world was concerned, by initial uncertainty concerning its cause. During the first phase of the investigation there were considerable disagreements between some of the participating groups of scientists. Many of these disagreements have now been resolved and it is to be hoped that the contributions in this volume will further help to resolve some of the outstanding uncertainties. However, although it is important to understand what happened at Lake Nyos in 1986, and why it happened, it is more important for the future of that area that further similar disasters should be avoided. We can only hope that this volume will help to establish a solid foundation for future research into ways of removing excess gas from the lake.

• Earthquake
• city
• erosion
• fossil
• gas
• hazard
• history
• natural disaster
• research
• seismic
• soil
• tectonics