The cycle of erosion was a model for stream erosion and landscape development proposed by William Morris Davis in the late 19th century. Davis' Stages in the fluvial cycle of erosion published in 1909 defined a young, mature, and old sequence in the development of river valleys and the landscape the rivers were eroding. His basic concept includes a rapid tectonic uplift, followed by cessation of the land, which allows the rivers and streams to reduce the surface to a level close to sea-level. The concept of peneplanation was a part of his model. In his model Davies picked up ideas of John Wesley Powell about limitation of erosion on land and concluded that sea level is the ultimate base level for sub-aerial erosion. Further he suggested that streams always have at least some gradient and temporary base levels, such as inland-lakes, are controlling points upstream of them.
The model developed by Davis, though important in historical context, is currently considered only a first approximation. Developments in the sciences of geology and geomorphology, especially the plate tectonics revolution of the 1960s and 70s, have confirmed the preliminary nature of the model.
Famous quotes containing the words cycle of, erosion and/or cycle:
“Only mediocrities progress. An artist revolves in a cycle of masterpieces, the first of which is no less perfect than the last.”
—Oscar Wilde (18541900)
“What if we fail to stop the erosion of cities by automobiles?... In that case America will hardly need to ponder a mystery that has troubled men for millennia: What is the purpose of life? For us, the answer will be clear, established and for all practical purposes indisputable: The purpose of life is to produce and consume automobiles.”
—Jane Jacobs (b. 1916)
“The lifelong process of caregiving, is the ultimate link between caregivers of all ages. You and I are not just in a phase we will outgrow. This is lifebirth, death, and everything in between.... The care continuum is the cycle of life turning full circle in each of our lives. And what we learn when we spoon-feed our babies will echo in our ears as we feed our parents. The point is not to be done. The point is to be ready to do again.”
—Paula C. Lowe (20th century)