Hydrothermal alteration and earth surface rock weathering: A basalt example

Geomorphologists have not devoted sufficient attention to the formation of clay minerals by hydrothermal activity. This paper describes the breakdown of freshly-quarried basalt by cyclic wetting and drying. Breakdown is attributed to the swelling of hydrothermally-derived smectite, and it is argued that the effects of endogenic processes can exert a significant control upon weathering behaviour under earth surface conditions.