1. The houses, people, traffic seemed

2. Thin fading dreams by day,

3. Chimborazo, Cotopaxi

4. They had stolen my soul away!

5. W. J. Turner

Introduction

The material discussed in Chapter 2 leads us to conclude that volcanoes occur in specific locations. Such locations include convergent plate margins (for example, volcanoes of the central Andes), islands that form higher parts of mid-oceanic ridges (Ascension Island in the Atlantic) and volcanic islands formed over hot spots in the middle of the oceans (Mauritius and Réunion) or continents (Tibesti, Chad). Volcanoes also occur in rift valleys. Mounts Kenya and Kilimanjaro of the East African Rift are probably the best-known of the rift valley volcanoes in the tropics. A number of less well-known ones, such as Nyamuragira and Nyiragongo of the Virunga Mountains, Central Africa also form prominent features on the regional landscape. Flood basalt erupted on a continental scale in the geologic past over parts of the tropics such as the Deccan Plateau of India and the Drakensberg of South Africa, giving these areas their characteristic landscape (Fig. 14.1).