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...M, XRD, CL, and XF methods|X-Ray Diffractometry]]. Carbonates more rich in calcite and/or aragonite are called [[limestone]]. Carbonate rocks composed mainly

Calcareous microfossils have shells composed of calcite or aragonite. These organisms are present in most marine and in some nonmar ...ifera are a group of unicellular organisms (protists) that secrete a rigid calcite or aragonite shell (or test). Fossils of these forms are found in sediments

...te]], [[clay]], and [[anhydrite]], etc. || [[Aragonite]], high- and low-Mg calcite, dolomite

...with other factors result in precipitation of aragonite or magnesium (Mg) calcite. ...ss of whether it is marine, brackish, or fresh and tend to alter to low-Mg calcite because most water is magnesium deficient. Their common form is isopachous

...areas that were alternately moist and dry [[anhydrite]], [[dolomite]], or calcite common | Calcite at base, grading up into calcite plus quartz, quartz plus clay minerals, and clays plus minor carbonate

* Burkhard, M., 1993, Calcite twins, their geometry, appearance and significance as stressstrain markers ...edman, M., Stearns, D., W., 1971, Relations between stresses inferred from calcite twin lamellae and macrofractures, Teton anticline, Montana: Geological Soci

* [[Open calcite crystals]] lining the fractures ...ritical elements of fieldwork|field work]] has shown that the same kind of calcite present in subsurface fractures within the Niobrara also occurs in fracture

...compartments are usually cemented by calcite. When unexpected pore-filling calcite is seen, a pressure seal should be considered a possibility. Any unusual po

* Sulfate minerals plugging the pores in grainstones (calcite plugging rarely significant but hard to leach if present) * Fibrous marine and vadose–phreatic sparry calcite cements plugging fenestral porosity

* Sparry calcite cement (sparite): pore-filling component precipitated during deposition. ...parry allochemical limestone that consists of allochems cemented by sparry calcite cement.[b]

...in calcite. Note that no petroleum inclusions were found in gas-stage TSR calcite, well D4, 4793.00 m (15,721.04 ft).<ref name=Jiangetal_2014>Jiang, Lei, Ric ...objectives of the petrographic analysis. Common stains are available for [[calcite]], [[dolomite]], [[ferrous carbonate]], [[K-feldspar]], and [[plagioclase]]

...pend on the composition of water and the equilibrium of every minerals. If calcite is formed, usually the shape is big. ...hydrocarbons in the stratigraphic trap as a result of loss updip porosity. Calcite cementation happened to overburden contact oil / water. (B) With folding co

* Mineralogical changes such as the formation of calcite, pyrite, uranium, elemental sulfur, and certain magnetic iron oxides and su

...rystallized, preserved in nodules or concretions, or replaced by pyrite or calcite.

| Grain coating or pore filling by [[calcite]], [[silica]], or [[dolomite]]

...oan [http://encyclopedia2.thefreedictionary.com/poikilotopic poikilotopic] calcite, and [[anhydrite]]

...olomite is either metastable or unstable with respect to a mixture of pure calcite plus pure dolomite. The same thing is true with respect to ideal dolomite p

...ts across stratigraphic units. It forms where authigenic minerals (usually calcite) fill the pore spaces. The '''bottom seal''' of regional compartments is us

* Vadose and upper phreatic sparry calcite cement often plugs primary and secondary porosity in the upper parts of seq

...ess. [[Porosity]] obliteration occurs when mosaics of coarsely crystalline calcite precipitate in large pores. Pressure solution occurs at higher pressures.

...ce between the pores of the rock grew wide. This resulted in the cavities. Calcite that has not been dolomitized will dissolve quickly and arising secondary p

...ure''; Partially or totally mineralized by postfracture cements, typically calcite, [[gypsum]], or silica.

...ar wacke-stones to grainstones. The principal occluding cements are sparry calcite and [[anhydrite]].

| Calcite

...e most common carbonate cement. Calcite cement is an assortment of smaller calcite crystals. The cement adheres itself to the framework grains, this adhesion ...tion of smectite and the precipitation of [[quartz]], ankerite and type II calcite cements. In addition to the increase in temperature and pressure, the spati

...7), though a subsequent study by Borrok et al. (2019) generally found that calcite concentration is greater near the base of the TMS. Porosity ranges from 4.

Table 1: Carbonate rock types having varying percentages of dolomite and calcite (after Leighton and Pendexter, 1962). Carbonate rock type Dolomite percentage (%) Calcite percentage (%)

| Calcite || Fibrous, bladed, granular, blocky, poikilotopic, syntaxial rim ...voir quality in sandstones and carbonates. Dolomitization of limestones or calcite cement in sandstones typically increases porosity and permeability. Similar

...th and regionally. Although chalk is usually stable, recrystallization and calcite precipitation are present on a regional scale. These changes in mechanical ...te rocks dolomitization, recrystallization, and changing from aragonite to calcite alter rigidity contrast. Other types of rocks such as clastics are affected

...e at over [[depth::13,000 ft]] depth in rock described as [[dolomite]] and calcite marble with graphitic inclusions.<ref name=ch11r30>Rozendal, R. A., and W.

...cally and chemically. Cementation precipitates secondary minerals, such as calcite, [[quartz]], and iron oxides, in the pores of sandstone.

...ese and lead.<ref name=pt05r107>Machel, H-G., 1985, Cathodoluminescence in calcite and dolomite and its chemical interpretation: Geoscience Canada, v. 12, p.

...equations can be combined to solve for porosity and to estimate volumes of calcite, [[quartz]], dolomite, clay, feldspar, anhydrite, and salt. Once porosity i | Calcite || CaCO₃ || 2.71 || 0 || –1. || 49.0 || 88.4 || 5.08 || 13.77

| Increased calcite/aragonite cementation in shallow marine phreatic zone where steep slopes or | Conditions favorable to precipitation of calcite and aragonite include areas where CO₂ degassing occurs, certain

...ompaction. Typical products of diagenesis include quartz, carbonate (e.g., calcite, dolomite, ankerite, and siderite), clay (e.g., illite, kaolinite, chlorite ...a ternary diagram with 100 percent of total quartz, total carbonate (e.g., calcite, dolomite), and total clay (e.g., illite, smectite) minerals as end members

...HF acid should not be allowed to contact calcium-bearing minerals such as calcite or [[dolomite]]. It is necessary to use HCl as a preflush or cation exchang

...HF acid should not be allowed to contact calcium-bearing minerals such as calcite or [[dolomite]]. It is necessary to use HCl as a preflush or cation exchang

.../BLTN05114.HTM Three-dimensional facies architecture and three-dimensional calcite concretion distributions in a tide-influenced delta front, Wall Creek Membe ...it appears probable that permeability barriers and baffles in the form of calcite-cemented concretionary layers occur along clinoforms in the Troll Field res

...stablished using fluid inclusions temperature (Th) utilizing assessment of calcite cements. Ultimately generating a burial history diagram ([[:file:AlfraihAlS

...robial bindstones having a fine lamination of irregular aspect and regular calcite sheets.

...ude mixed layer illite/smectite, illite, chlorite, quartz overgrowths, and calcite. Detrital clay further limits reservoir quality. The Codell in Wattenberg i ...ygiene sandstones<ref name=PortWeim1982 />. Leaching of calcite cement and calcite-replaced grains and matrix and dissolution of framework grains and pseudoma

...ites]], more refractory (highly variable late oil–to–dry gas windows); and calcite, in [[metagenesis]].<ref name=J&J2007>Jarvie, B. M., and D. M. Jarvie, 2007 ...s that precipitate. This was also shown by the carbon isotopic analysis of calcite cements, by Pitman et al.,<ref name=Ptmn2001 /> that were shown to be deriv

...in the context of the evolution of the sea-water chemistry (aragonite vs. calcite sea, KCl vs. MgO₄ evaporites), the global sea-level curve, the m ...in the context of the evolution of the sea-water chemistry (aragonite vs. calcite sea, KCl vs. MgO₄ evaporites), the global sea-level curve, the m

...hytoplankton and algal-bacterial origin. Cements are mainly represented by calcite, dolomite, and microgranular quartz<ref name=Ktzmn>Kietzmann D. A., F. Gonz ...rtz, and plagioclase grains; cements are microgranular quartz and granular calcite; mineralogy records 45% siliciclastic, 30% carbonate, 20% clay; porosity is

...gh fractures may be present, they are usually healed with minerals such as calcite. Of course, having a brittle rock typically with a high silica content is a

...™, manufactured by Schlumberger) logs. Most observed natural fractures are calcite cemented and healed.