| A | B |
|---|
| basin | depression |
| rift valley | a long, thin vally created by the moving apart of the continental plates |
| escarpment | a steep slope with a nearly flat plateau on the top |
| Mount Kilimanjaro | a volcano in Tanzanina in Africa, also Africa's higest peak |
| aquifers | an underground layer of rock that stores water |
| oasis | a place where water from an aquifer has reached the surface; it supports vegetation and wildlife |
| serengeti plain | a tropical grassland in East Africa |
| canopy | the area encompassing the tops of the trees in a rain forest abut 150 feet above ground |
| Niger Delta | delta of the Niger River and an area of Nigeria with rich oil deposits |
| sahel | a narrow band of dry grassland, runnign east to the west on the southern edge of the sahara, this is used for farming and herding |
| silt | losse sedimentary material containing very samll rock particles formed by river deposits and very fertile |
