(a) Definition of weathering: Weathering is the disintegration or decomposition of rocks in situ by physical, chemical or biological processes. (b) Factors that affect weathering: temperature Changes/climate, rainfall/moisture climate, types/nature of rocks; living organisms (plants and animals), - relief/topography; time.
(c) Description or the processes of exfoliation: physIcal mechanical weathering, occurs in desert/arid regions, - plutonic rocks are exposed to the surtace by erosIon, - the removal of the heavy overlying rock materials relax the pressure on the rock; the rocks expand slightly in volume around the exposed surtaces, the expansion makes the exposed side weak and more vulnerable to external forces, expansion causes cracks parallel to the surface, - thin layers on the exposed surface peel off and are called sheeting structures - high temperatures at day causes outer layers of exposed rocks to expand, - drop in temperatures at night causes outer layers of rocks to contract faster than the inner layers.