Weathering processes and forms

Abstract This chapter considers the various processes of rock weathering, starting with physical weathering processes (frost, wetting and drying, heating and cooling or insolation weathering, and salt weathering (haloclasty)). It then turns to a consideration of chemical weathering processes and to the remarkable increase of interest in biological (organic) processes. This is followed by a discussion of rates of weathering and the techniques that have been developed to study them, including the analysis of sediment loads and the measurement of surface changes with instruments like the micro-erosion meter. The global carbon cycle and the links between geomorphology and soils are also considered. Progress in the study of weathering forms such as alveoli, pits and tafoni is described. There is also a discussion of materials deposited as a consequence of chemical weathering, such as various types of duricrust. Finally, weathering hazards are addressed together with an assessment of the ways in which humans have accelerated some weathering processes.