Dolomitization

Dolomitization is a process by which dolomite is formed when magnesium ions replace calcium ions in calcite. It is common for this alteration into dolomite to take place due to evaporation of water in the sabkha area.[1] Dolomitization involves substantial amount of recrystallization. This process is described by the stoichiometric equation:[2]

2CaCO3(limestone) + Mg2+ ↔ CaMg(CO3)2(Dolomite) + Ca2+

Dolomitization depends on specific conditions which include low Ca:Mg ratio in solution, reactant surface area, the mineralogy of the reactant, high temperatures which represents the thermodynamic stability of the system, and the presence of kinetic inhibitors like sulfate.[2]

If the kinetic inhibitors and high temperatures are compatible then dolomitization can take place in saline environments above thermodynamic and kinetic saturation with respect to dolomite. This type of environment includes, freshwater and seawater mixing zones, normal saline to hypersaline subtidal environments, schizohaline environments and hypersaline supratidal environments. When requirements are fulfilled dolomitization can take place in alkaline environments which are those under the influence of bacterial reduction and fermentation processes, and areas with high input alkaline continental groundwaters. Environments with high temperatures (about 50°C) like subsurface and hydrothermal environments are conducive to dolomitization.[1]

See also

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References


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Look at other dictionaries:

  • dolomitization — (Amer.) n. geochemical process of converting into dolomite, changing limestone into dolomite (also dolomitisation) …   English contemporary dictionary

  • dolomitization — /doh leuh muy teuh zay sheuhn, mi , dol euh /, n. Geol. the conversion of limestone into dolomite. [1860 65; DOLOMITIZE + ATION] * * * ▪ mineralogy       process by which limestone is altered into dolomite; when limestone comes into contact with… …   Universalium

  • dolomitization — dolomitizacija statusas T sritis chemija apibrėžtis Kalcio karbonato (aragonito arba kalcito) virtimas dolomitu. atitikmenys: angl. dolomitization rus. доломитизация …   Chemijos terminų aiškinamasis žodynas

  • dolomitization — noun Date: 1862 the process of converting into dolomite • dolomitize transitive verb …   New Collegiate Dictionary

  • dolomitization — noun The conversion of a limestone rock into dolomite by replacement of calcium by magnesium …   Wiktionary

  • dolomitization —    The process whereby limestone becomes dolomite by the substitution of magnesium carbonate for part of the original calcium carbonate [10] …   Lexicon of Cave and Karst Terminology

  • dolomitization — do·lo·mit·i·za·tion …   English syllables

  • dolomitization — ˌ ̷ ̷ ̷ ̷ˌmīd.ə̇ˈzāshən, məd. noun ( s) : the process of converting into dolomite * * * /doh leuh muy teuh zay sheuhn, mi , dol euh /, n. Geol. the conversion of limestone into dolomite. [1860 65; DOLOMITIZE + ATION] * * * dolˈomitīzātion or… …   Useful english dictionary

  • dolomitizations — dolomitization (Amer.) n. geochemical process of converting into dolomite, changing limestone into dolomite (also dolomitisation) …   English contemporary dictionary

  • dolomite — dolomitic /dol euh mit ik/, adj. /doh leuh muyt , dol euh /, n. 1. a very common mineral, calcium magnesium carbonate, CaMg(CO3)2, occurring in crystals and in masses. 2. a rock consisting essentially or largely of this mineral. [1785 95; < F,… …   Universalium


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