I believe a low land is like an area where the land is at, near, or below the sea level of sea and where there are not usually mountains or large hills.
The eastern African rift valley is an active plate margin and is an active Continental rift one in Africa and started to form about 20 - 25 million years ago in the Miocene.
Is a narrow zone that develops as a divergent plate boundary as the processes of the spitting of the tectonic plates i.e Somalian and the Nubian plate. Breaking away of this plate will lead to the formation of the a new oceanic basin.
