Planation surface

In geology and geomorphology a planation surface is a large-scale surface that is almost flat with the possible exception of some residuals hills. The processes that form planation surfaces are labelled collectively planation and are exogenic (chiefly erosion). Planation surfaces are planated regardless of bedrock structures. On Earth they constitute some of the most common landscapes.Peneplains and pediplains are types of planation surfaces planated respectively by "peneplanation" and "pediplanation". In addition to these there are planation surfaces proposed to be formed by cryoplanation, marine processes, areal glacial erosion and salt weathering. The term planation surface is often preferred over others because some more specific planation surface types and processes remain controversial.Etchplains are weathered planation surfaces.

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