Micrite

Meleke in the Gerofit Formation (Turonian) near Makhtesh Ramon, southern Israel; a type of micrite.

Micrite is a limestone constituent formed of calcareous particles ranging in diameter up to four μm formed by the recrystallization of lime mud.[1][2]

The term was coined in 1959 by Robert Folk for his carbonate rock classification system.[2] Micrite is derived from MICRocrystalline calcITE. In the Folk classification micrite is a carbonate rock dominated by fine-grained calcite. Carbonate rocks that contain fine-grained calcite in addition to allochems are named intramicrite, oomicrite, biomicrite or pelmicrite under the Folk classification depending on the dominant allochem.

Micrite is lime mud, carbonate of mud grade. Micrite as a component of carbonate rocks can occur as a matrix, as micrite envelopes around allochems or as peloids. The origin of micrites is still a problem in carbonate sedimentology due to the non-uniqueness of the processes generating it.[3] Micrite can be generated through multiple processes. In lakes and some marine environments, lime mud that could become micrite can form chemically or biochemically through whiting events, whereas in warm stratified marine waters it might be forming chemically.[4] Alternatively, microbial process known as micritization may lead to micrite formation.[5] Other processes which might produce micrite include the disaggregation of peloids, bioerosion, the mechanical degradation of larger carbonate grains and dissolution-reprecipitation processes.[6][7]

  1. ^ McLane, Michael, Sedimentology, Oxford University Press, 1995, p. 238 ISBN 0-19-507868-3
  2. ^ a b Flügel, Erik, Microfacies of Carbonate Rocks: Analysis, Interpretation and Application, Springer, pp 74-94, 2004 ISBN 978-3-540-22016-9
  3. ^ Tucker, Maurice E. (1990). Carbonate sedimentology. Oxford [England]: Blackwell Scientific Publications. ISBN 9781444314175.
  4. ^ Bialik, Or M.; Sisma-Ventura, Guy; Vogt-Vincent, Noam; Silverman, Jacob; Katz, Timor (24 September 2022). "Role of oceanic abiotic carbonate precipitation in future atmospheric CO2 regulation". Scientific Reports. 12 (1): 15970. doi:10.1038/s41598-022-20446-7. PMC 9509385. PMID 36153366.
  5. ^ Kabanov, P. B. (30 January 2003). "Products of micritization: evidences of microbial activity at and below the seafloor of the Upper Moscovian epicontinental basin of central European Russia". In Hoover, Richard B.; Rozanov, Alexei Y.; Lipps, Jere H. (eds.). Instruments, Methods, and Missions for Astrobiology VI. Vol. 4939. p. 141. doi:10.1117/12.501867. S2CID 129323579.
  6. ^ Schlager, Wolfgang (2005). Carbonate Sedimentology and Sequence Stratigraphy. Tulsa, OK. ISBN 1565761162.{{cite book}}: CS1 maint: location missing publisher (link)
  7. ^ Jerry Lucia, F. (September 2017). "Observations on the origin of micrite crystals". Marine and Petroleum Geology. 86: 823–833. Bibcode:2017MarPG..86..823J. doi:10.1016/j.marpetgeo.2017.06.039.