Nairobi, April 7 -- Geologists say the Great Rift Valley was formed by the Earth's tectonic plates pulling away from each other, about 30 million years ago. The process continues, they say, at about six mm per year, with an eventual split. A new ocean basin will separate parts of East Africa into a new island continent. But don't worry yet, it will take another five million years!

Beyond geology, rather specialised branches of science study the Rift. Plate tectonics studies how the Earth's lithospheric plates move and pull apart to create the Rift. Geomorphology focuses on the physical features of the valley floor, such as the escarpments, mountains, and how erosion shapes them.

Volcanologists study the numerous volcanoes (like Menegai,...