The similarity between Central Africa, Amazon and Indonesia is quite striking. The three areas are found at equator, span 30°, and are found with 60° interval. Also, volcanic and tectonic activity is found in context with the relevant mantle convection division lines, marking the large scale polygon.
The volcanic activity in eastern Africa is related to the Great Rift Valley, which is closely related to the tectonics formed by the east corner of the polygon of Central Africa.
