What is Sedimentology?
[[File:Triassic Utah.JPG|thumb|right|Middle [[Triassic]] marginal marine sequence of [[siltstone]]s (reddish layers at the cliff base) and [[limestone]]s (brown rocks above), Virgin Formation, southwestern [[Utah]]]] [[File:Lower antelope 3 md.jpg|thumb|Lower [[Antelope Canyon]], [[Arizona]], was carved out of the surrounding [[sandstone]] by mechanical and chemical weathering. Wind, sand, and water from [[flash flood]]ing are the main weathering agents]] '''Sedimentology''' is the study of [[sediment]]s such as sand,<ref>Siever, Raymond 1988. ''Sand''. New York: Scientific American Library. {{ISBN|0-7167-5021-X}}</ref> mud (silt),<ref>Potter P.E; Maynard J.B. and Depetris P.J. 2005. ''Mud and mudstones: introduction and overview''. Berlin: Springer. {{ISBN|3-540-22157-3}}</ref> and clay.<ref>Millot, Georges 1970. ''Geology of clays: weathering, sedimentology, geochemistry''. Berlin: Springer Verlag. {{ISBN|0-412-10050-9}}</ref> How they are laid down today is used to understand how rocks were formed.<ref>Nichols, Gary 1999. ''Sedimentology & stratigraphy''. Malden, MA: Wiley-Blackwell. {{ISBN|0-632-03578-1}}</ref> A person who studied sedimentology is called Sedimentologist. They use their understanding of modern processes to interpret [[sedimentary rocks]] and sedimentary structures.<ref>Prothero, Donald R. and Schwab, Fred 1994. ''Sedimentary geology: an introduction to sedimentary rocks and stratigraphy'', San Francisco: Freeman. {{ISBN|0-7167-2726-9}}</ref> Sedimentary rocks cover most of the [[Earth]]'s surface, record much of the [[History of Earth|Earth's history]], and contain the [[fossil record]]. Sedimentology is closely linked to [[stratigraphy]], which is the study of the physical and temporal (time) relationships between rock layers or [[stratum|strata]]. The idea that the processes affecting the earth today are the same as in the past is called [[uniformitarianism]]. It is the basis for finding out how sedimentary features in the rock record were formed. By comparing similar features today to