In very dry regions, such as arid desert areas with horizontal sedimentary rock layers where the resistance of the rock layers vary, the formation of a canyon is most likely to occur. this is due to mechanical weathering predominating in these areas this supplies a lot of material to perform abrasion.
River and climate
The river which forms in such arid dry desert
like conditions are exotic streams/rivers which means they are not supplemented
by groundwater but by the source, where there is a large supply of water.