Editing Reef (section)

==== Mounds ====
Both mounds and reefs are considered to be varieties of organosedimentary buildups, which are sedimentary features, built by the interaction of organisms and their environment. These interactions have a synoptic relief and whose biotic composition differs from that found on and beneath the surrounding [[sea floor]]. However, reefs are held up by a macroscopic skeletal framework, as what is seen on coral reefs. [[Corals]] and calcareous algae grow on top of one another, forming a three-dimensional framework that is modified in various ways by other organisms and inorganic processes.<ref name=":0">{{Cite web |title=Reading: Shorelines {{!}} Geology |url=https://courses.lumenlearning.com/geo/chapter/reading-shorelines/ |access-date=2024-04-20 |website=courses.lumenlearning.com}}</ref>

Conversely, mounds lack a macroscopic skeletal framework. Instead, they are built by microorganisms or by organisms that also lack a skeletal framework. A microbial mound might be built exclusively or primarily by [[cyanobacteria]]. Examples of [[biostrome]]s formed by cyanobacteria occur in the [[Great Salt Lake]] in [[Utah]], United States, and in [[Shark Bay]] on the coast of [[Western Australia]].<ref name=":0" /><ref>{{Cite journal |last=Wood |first=Rachel |date=2001-12-15 |title=Are reefs and mud mounds really so different? |url=https://www.sciencedirect.com/science/article/pii/S0037073801001464 |journal=Sedimentary Geology |series=Carbonate Mounds: sedimentation, organismal response, and diagenesis |volume=145 |issue=3 |pages=161–171 |doi=10.1016/S0037-0738(01)00146-4 |bibcode=2001SedG..145..161W |issn=0037-0738|url-access=subscription }}</ref>

Cyanobacteria do not have skeletons, and individual organisms are microscopic. However, they can encourage the precipitation or accumulation of calcium carbonate to produce distinct sediment bodies in composition that have relief on the seafloor.  Cyanobacterial mounds were most abundant before the evolution of shelly macroscopic organisms, but they still exist today. [[Stromatolite]]s, for instance, are microbial mounds with a laminated internal structure. Whereas, [[bryozoan]]s and [[crinoid]]s, common contributors to marine sediments during the [[Mississippian (geology)|Mississippian period]], produce a different kind of mound. Although bryozoans are small and crinoid skeletons disintegrate, bryozoan and crinoid meadows can persist over time and produce compositionally distinct bodies of sediment with depositional relief.<ref name=":0" /><ref>{{Cite journal |last=crossref |title=Chooser |url=https://chooser.crossref.org/ |access-date=2024-04-20 |website=chooser.crossref.org |language=en |doi=10.2307/3514838|jstor=3514838 |url-access=subscription }}</ref>

The [[Proterozoic]] [[Belt Supergroup]] contains evidence of possible [[microbial mat]] and dome structures similar to stromatolite and chicken reef complexes.{{clarify|what are chicken reef complexes?|date=November 2024}}<ref name=":0" /><ref>{{Cite journal |last=Schieber |first=Jürgen |date=1998 |title=Possible indicators of microbial mat deposits in shales and sandstones: examples from the Mid-Proterozoic Belt Supergroup, Montana, U.S.A. |url=https://sepm04.sitehost.iu.edu/PDF/JS-J24-microbial_mat_challenge |journal=Sedimentary Geology |volume=120 |issue=1 |pages=105–124|doi=10.1016/S0037-0738(98)00029-3 |bibcode=1998SedG..120..105S |url-access=subscription }}</ref>