The scientific study of the processes and impacts of ice sheets, valley glaciers, and other ice masses on the Earth's surface, both on land and in ocean basins. The processes include understanding how ice masses move, erode, transport, and deposit sediment. The impacts on glaciated landscapes are enormous in terms of topographic change and floral and faunal modification. In those areas peripheral to glaciated areas, drainage patterns are altered, and climatic, vegetation, and soil conditions are severely changed. In addition, glacial geology involves studying the causes of glaciation, the chronology of glaciation in geologic time (the retreat and advance of ice masses at all scales), glacial stratigraphy, sea-level change, and how glaciations affect oceans, climate, flora, fauna, and human society globally. Closely allied to glacial geology are studies into the physics of ice masses (glaciology), global climatology (paleoclimatology), and paleoenvironmental reconstructions (paleoecology).