Wind transportation can cause deflationary hollows, another landform created by a present day process. This transportation mainly occurs in the form of saltation, and the wind removes the finer material, leaving a stony hollow behind. Although this is true for most hollows, some hollows – mostly the biggest ones, are not caused by deflation as the scale of them is too large.
The final landform formed from Aeolian processes is the sand dune. The variety of sand dunes which are visible in the desert are shaped by wind direction – with velocity and fetch having an effect. However, the quantity of sand which the dunes are composed of indicates that although the shape is altered by the present day wind, the sand was deposited there in the past.
The present day fluvial processes also produce a wide range of landforms. Wadis are flat floored river channels which for much of the year contain no water. Many of the shallow wadis are created by present day fluvial erosion processes, such as abrasion and corrosion, however many of the steep sided gorges are created by past processes, during a time in which there was more water than there is present today, and the scale of some of these gorges indicates that as well as the down cutting, there may have also bee. some tectonic uplift, for example on the Colorado plateau.
Lateral erosion has created the landforms of pinnacles, mesas and buttes. These are pillars of mechanically stronger rock, which have resisted the fluvial erosion better than the surrounding rock, and are therefore left standing. The mechanical strength of the rock means that the faces are very steep.
On a small scale, alluvial fans and bahadas are a product of present day fluvial deposition. These form when a river reaches flat ground, and therefore loses energy, causing it to deposit the load which it had been carrying due to a lack of energy.
The main argument that desert landforms are a product is past process is the scale of the landforms and the lack of water in the present day. For example, the amount of sand present in some dunes makes it impossible to be formed by wind alone. Other relic dunes are not even being worked by wind, and were produced in a time during the Holocene period when they were active
As the cliffs in deserts are weathering limited, these are a product of present day processes. This means that the rate of weathering is slower than the rate of transport, and unlike the transport limited slopes of more temperate climates, no material such as regolith and soil can accumulate. The transport limited slopes have a build up of this material on the scarp slope, and over time this becomes covered in vegetation and rounded. On the slopes of the desert, such as the Flaming Gorge in Utah, all of the eroded material is transported away by rivers, leaving a very angular slope.
As weathering, the breaking down of rocks in situ involving little/no movement, in deserts is a very slow process, it can be assumed that that this is not a present day process, but a process which happens over a long period of time and continues into the present day. Weathering in deserts is such a slow process because there is a lack of moisture and soil/organic acids, and the rocks are often mechanically strong. However, this means that different desert locations have different rates of weathering, and therefore in some the weathering could be classed as a present day process – for example although the process of wetting and drying may take a large amount of time, the granular disintegration of sandstone – where different crystals in the rock heat up and cool down at different rates – is constantly happening due to the high diurnal temperature ranges, and therefore these landforms are produced by present day processes. Landscapes formed by weathering must have been created during a time in which more water was present.
In conclusion, many of the landscapes seen in the desert today are a product of present day processes shaping the land over a long period of time. However, the sheer scale of some of these indicates that the present day processes worked in combination with things ling tectonic uplift, and some landforms were not created by present day processes at all.