Detrital sedimentary graded beds are formed from erosional, depositional, and weathering forces. Aeolian landforms are typically described in two categories&colon; erosional and depositional. Limestone is partially soluble, especially in acid, and therefore forms many erosional landforms. Plastic moulding, gouging and other glacial erosional features become present upon the glacier's retreat. Stratified sediment was deposited rapidly on the high-relief erosional surface. It mapped and categorized areas of tributary drainage and erosional features on the watershed. The exposed bedrock is attacked by water, ice, wind and other erosional agents. This erosional process softens and rounds the features of the crater. These two rivers on the sandur display drastically different erosional patterns. The 400.000 year long conservation is attributed to the travertine's remarkable resilience to erosional processes. Hoodoo shapes are affected by the erosional patterns of alternating hard and softer rock layers. These erosional gradient is a habitat for many plant communities. On Earth, materials cemented by silica are highly resistant to all kinds of erosional forces. Mountain ranges are constantly subjected to erosional forces which work to tear them down. They are of diverse structure and of various stages of erosional development.