The role of episodic plain formation and continuous etching and stripping processes in the End-Tertiary landform development of S.E. Kenya

Scarp retreat and related plain formation in the southeastern Kenyan landscape were episodic processes and associated with periods of high base-levels. Both sedimentation and erosion contributed to landscape leveling. Correlation of tectonic movements in the interior and regional base-level changes shows that a tectonic control over the Late Tertiary plain formation is more than likely. The proposed leveling process opposes the pediplanation concept in being triggered off by base level rise instead of base-level lowering. Moreover, it is not continuous, but seems to come to an almost stand still as soon as the regional base level is lowered. It further allows weathering and erosion processes to continue in areas outside the reach of base-level changes and can therefore solve the apparent paradox between plain formation and contemporaneous etching and stripping processes.