リズマイト

thumb|right|240px|alt=A brown rock or sediment face with horizontal layers, 18 of which are clearly visible. Some of the layers are obviously thicker than others - presumably the result of differences in annual deposition rates due to seasonal variations.|Pleistocene age varves at [[Scarborough Bluffs, Toronto, Ontario, Canada. The thickest varves are close to 2 cm thick. ]] A rhythmite consists of layers of sediment or sedimentary rock which are laid down with an obvious periodicity and regularity. They may be created by annual processes such as seasonally varying deposits reflecting variatio