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Microbialite is a benthic sedimentary deposit made of carbonate mud (particle diameter < 5 μm) that is formed with the mediation of microbes. The constituent carbonate mud is a type of automicrite (or authigenic carbonate mud); therefore, it precipitates in situ instead of being transported and deposited. Being formed in situ, a microbialite ...
The silicate carbonates are double salts that contain both silicate and carbonate in their formula. Most compounds are natural minerals containing calcium or rare earth elements. However, some have been made experimentally. Silicate carbonate minerals can be formed in limestone metamorphosed by heating from igneous intrusions. [ 1 ]
Biomineralization: Complete conversion of organic substances to inorganic derivatives by living organisms, especially micro-organisms. [1] Fossil skeletal parts from extinct belemnite cephalopods of the Jurassic – these contain mineralized calcite and aragonite. Biomineralization, also written biomineralisation, is the process by which living ...
A silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula [SiO(4-2x)−. 4−x] n, where 0 ≤ x < 2. The family includes orthosilicate SiO4− 4 (x = 0), metasilicate SiO2− 3 (x = 1), and pyrosilicate Si2O6− 7 (x = 0.5, n = 2). The name is also used for any salt of such ...
Microbiologically induced calcium carbonate precipitation (MICP) is a bio-geochemical process that induces calcium carbonate precipitation within the soil matrix. [ 1 ] Biomineralization in the form of calcium carbonate precipitation can be traced back to the Precambrian period. [ 2 ] Calcium carbonate can be precipitated in three polymorphic ...
The carbonate-silicate cycle is the primary control on carbon dioxide levels over long timescales. [ 3 ] It can be seen as a branch of the carbon cycle, which also includes the organic carbon cycle, in which biological processes convert carbon dioxide and water into organic matter and oxygen via photosynthesis. [ 5 ]
Biogenic silica (bSi), also referred to as opal, biogenic opal, or amorphous opaline silica, forms one of the most widespread biogenic minerals. For example, microscopic particles of silica called phytoliths can be found in grasses and other plants. Silica is an amorphous metalloid oxide formed by complex inorganic polymerization processes.
The alkali–silica reaction (ASR), also commonly known as concrete cancer, [ 3 ] is a deleterious internal swelling reaction that occurs over time in concrete between the highly alkaline cement paste and the reactive amorphous (i.e., non-crystalline) silica found in many common aggregates, given sufficient moisture.