Before revision: It is created by the erosional forces of cascading water on the rocks at formation's base where the water impacts.Marshak, Stephen, 2009, Essentials of Geology, W. W. Norton & Company, 3rd ed.
After revision: theIt is created by the erosional forces of cascading water on the rocks at formation's base where the water impacts.Marshak, Stephen, 2009, Essentials of Geology, W. W. Norton & Company, 3rd ed.