The study of past hydrology. Evidence for hydrological changes during previous periods of Earth history comes from the alteration, deposition, and erosion of rocks from these periods. Palaeohydrology includes changes in flora and fauna assemblages that have been strongly influenced by changes in hydrology. See Willard et al. (2011) The Holocene 21, 2, 305 on a pollen-based palaeohydrologic reconstruction from North Carolina.