Paleosurface

A paleosurface is a surface of considerable age created by erosion, a term used in geology and geomorphology; it may be flat or carry significant relief. Large, flat paleosurfaces, known as planation surfaces, survive and get studied more often than smaller, uneven ones, though irregular paleosurfaces do exist, such as the etchsurfaces of the Sudetes mountains. A peneplain becomes a paleosurface once it is cut off from the base level toward which it had been grading, and paleosurfaces matter to geologists and geomorphologists for different reasons: geologists read them for evidence of constructive crustal processes such as uplift, while geomorphologists read them for the erosional and weathering processes that shaped them.