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Dolerite noun. (geology) A fine-grained basaltic rock. Dolomite noun. (mineral) A saline evaporite consisting of a mixed calcium and magnesium carbonate, with the chemical formula CaMg (CO 3) 2; it also exists as the rock dolostone.
The carbonate-magnetite thermometric pairs of the fine-grained dolomite indicate a range of 350–540 °C, which is probably lower than that of the original main magmatic emplacement. This supports the distinction made between the original coarse-grained dolomite marble and dyke composition from the later fine-grained dolomite.
Heterogeneous grain-size marble consists of both coarse- and fine-grained dolomite in the same rock sample (Fig. 2g). The coarse dolomite is typically embedded within a matrix of fine-grained dolomite (Fig. 2g). This texture is similar to those previously identified by Wang et al. and Lai et al. . Fluorite and bastnäsite are commonly found ...
Coarse- and fine-grained dolomite deformed at low temperature (T ≤ 700°C for coarse-grained natural dolomite, T < 700°C for fine-grained natural and synthetic dolomite) exhibit mechanical behavior that is nearly plastic; differential stresses are insensitive to strain rate, fitted either by …
Dolomite has three directions of perfect cleavage. This may not be evident when the dolomite is fine-grained. However, when it is coarsely crystalline the cleavage angles can easily be observed with a hand lens. Dolomite has a Mohs hardness of 3 1/2 to 4 and is sometimes
Thick-bedded, mainly dark bluish-gray dolomite; some light-gray fine-grained dolomite. Yields many large masses of dense jagged chert, much more than any other formation in Alabama. Chert very sparingly fossiliferous. Thick-bedded bluish-gray finely crystalline dolomite, highly siliceous, with silica incrustations or network of silica ridges on ...
Dolomite and limestone: Sedimentary rock units of interbedded dolomite and limestone (see definitions of dolomite and limestone). Gray shale: A fine-grained sedimentary rock formed from the compaction of clay, silt, or mud. Clayey to silty texture; commonly splits along planar or irregular bedding planes.
Dolomite in the upper part is massive, fine- to medium-grained, pitted, friable, mottled and medium- to medium-dark-gray. A lower dolomite sequence is thin- to medium-bedded, stylolitic, fine-grained, and medium gray. Shaly dolomite and clastic interbeds of varicolored
Nowadays, dolomite coming from this region is still conventionally used as fertilizer[8]. On the other hand, ultra fine grain magnesium carbonate used as raw material for drugs and filler in industries is still imported from abroad. Dolomite can be processed to obtain ultra fine grain magnesium carbonate.
Limestone is an occurring type of sedimentary carbonate rock found on Earth's surface. It is formed when crystals of calcium carbonate precipitate out of water containing dissolved calcium. Limestone is composed of minerals such as calcite and aragonite. Limestone consists of 80 percent calcite and Dolomite with more than 50% calcium carbonate.
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Longview Dolomite - Siliceous, gray, fine-grained, medium-bedded dolomite; interbeds of gray limestone in upper part. Thickness about 300 feet; and Chepultepec Dolomite - Light-gray, fine-grained, well-bedded dolomite, moderately cherty; fine-grained limestone locally in upper part; quartz sandstone beds at base. Thickness about 800 feet.
2. Medium grain dolomite. Medium grain dolomite mainly consists of dense and subhedral grains with inter-granular boundaries of planer-s (Table 1). Dolomite grain size varies between 20 μm to 100 ...
Description: The Shakopee Dolomite of Indiana is a pure to impure and generally very fine grained to fine-grained dolomite containing some chert and interbeds of shale, siltstone, and sandstone. In southern Indiana, where younger beds of the Shakopee are preserved, fine- to medium-grained dolomite increases in abundance upward.
Locations of fine-grained dolomite occurrences (red dots). Petrographic features of the investigated dolomites are very similar and differ substantially from those of the Thasian dolomites. All fine-grained dolomites investigated here exhibit MGS (maximum grain-size) below 1 mm. Texture is very regular-mosaic with straight grain-boundaries.
In the Reveille Range, the Ely Springs Dolomite is composed of an upper 50 foot sequence of light-gray, fine-grained, poorly bedded dolomite, overlying a lower sequence composed of about 40 feet of dark-gray, fine-grained dolomite with abundant brown-gray chert nodules (Ekren, Rogers, and Dixon, 1973).
Fine grained dolomite. Mimetype image/jpeg Filename FC67-03_Box_053.JPG Originator Group Added to Astropedia 3 August 2017 Modified 3 November 2017 General Series Id 03 Edition 53 Keywords Target Earth Lithology Geospatial Information Quad Name …
Dolomite is a very common mineral, and is known for its saddle-shaped curved crystal aggregates. A unique, isolated Dolomite occurrence in Eugui, Spain has provided colorless transparent crystals that resemble the Iceland Spar variety of Calcite.The occurrence of Kolwezi, in the Congo, has produced some fascinating, cobalt-rich specimens that are a beautiful hot pink color and highly popular.
In the Reveille Range, the Ely Springs Dolomite is composed of an upper 50 foot sequence of light-gray, fine-grained, poorly bedded dolomite, overlying a lower sequence composed of about 40 feet of dark-gray, fine-grained dolomite with abundant brown-gray chert nodules (Ekren, Rogers, and Dixon, 1973).
Color: Sevy Dolomite / Chert is homogenous and ranges from a light or dark gray to an olive gray or pinkish or orangish gray. Texture: Course to medium grain dolomite and a medium to fine grain chert. Luster: Translucency: Opaque Silica Fabrics / Fossils: Few fossils including brachiopods, bryozoans, and crinoids Patina: Dolomite ranges from gray to a yellowish gray.
Textures of carbonate rocks are extremely variable. Textures can vary from those similar to clastic sediments, showing characteristic grain sizes, sorting, and rounding, to those produced by chemical precipitation. In carbonates the matrix can range from fine grained carbonate mud to crystalline calcite or dolomite.
Fine-grained structure: one of the secondary structures, some of the dolomite in the ore has a particle size between 0.06 and 0.3 mm and a degree of autotroph, and the particles are distributed in close contact with each other, or between collophane, forming this structure, as shown in Figure 1(e).Micropowder crystal structure: one of the secondary structures, some dolomite and quartz are in ...
for the Carnegie Institution describe a number of very fine-grained, dense dolomites of considerable extent and thickness. The pre-Cambrian dolomite formation of the Baraboo' syn- clinal is singularly fine grained. The Niagara limestone of Wis- consin, a dolomitic formation, is generally a very even-textured, fine-grained, and compact rock.
Naturally and experimentally deformed dolomite aggregates form localized zones characterized by high shear strain and very fine grain size. Microstructures in both naturally and experimentally deformed samples indicate that grain size reduction takes place by recrystallization-accommodated dislocation creep. However, experimental stress-strain results for coarse-grained dolomite that develop ...
The dolomite aquifers are moderately to highly susceptible to contamination because of abundant vertical fractures exposed at or near the surface. The southwestern part of the region is an exception; there the overlying fine grained material is greater than 50 ft thick, resulting in lower susceptibility to contamination. -from Author",
Dolomite grain size reduction to ~10 μm took place by grain fracturing; calcite grain size reduction to ~0.5 μm took place by plasticity-induced fracturing. The ultrafine-grained calcite deformed by diffusion creep and strain localized within the fault parallel calcite veins, while strain did not localize in the fine-grained dolomite.
Dolomite has three directions of perfect cleavage. This may not be evident when the dolomite is fine-grained. However, when it is coarsely crystalline the cleavage angles can easily be observed with a hand lens. Dolomite has a Mohs hardness of 3 1/2 to 4 and is sometimes found in rhombohedral crystals with curved faces.
Dolomites are mostly medium to fine grained and best preserve the original features, form in semi-arid regions on high intratidal to supratidal flats [10]. On the basis of very fine grained size of dolomite crystals and syndepositional sedimentary structures like herringbone cross bedding, trough cross bedding, hummocky cross stratification, we ...
Steel manufacturers prefer dolomite of the following composition for dead burning: MgCO 3 - 35% Min. SiO 3 - 1% Max. Fe 3 O 3 +Al 3 O 3 - 1.5% Max. CaCO 3 - Remainder Dolomite for use as flux in steel metallurgy should be hard, compact and fine-grained so that it can stand the burden of the batch in the blast furnace as well as the basic steel ...
Consists of two kinds of dolomite: a white to buff or gray, fine-grained, argillaceous, earthy textured, relatively soft variety known as "cotton rock"; and a gray, medium-grained, more massive variety that weathers hackly on the surface and becomes dark upon exposure.
The second experimentally deformed dolomite shear zone (Experiment D-26, Holyoke et al., 2014a, Fig. 1B) consists of a synthetic fine-grained (d = 2.5±1.5 μm) dolomite layer (~735 μm thick) placed between cylindrical coarse-grained Madoc dolomite host blocks pre-cut at 45° to the cylindrical axis. The fine-grained dolomite layer was cut at 45° to the length of a core collected from a fine ...
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Grain Size 1/256-2 mm. (part 1) Crystalline, Clastic, Bioclastic, Oolitic, Etc. Composition of Major Fraction: Composition as Indicated in left column (prefix appropriate names for mixtures) Chiefly Calcite or Dolomite: Composition of Minor Fraction < 10% Minor Fraction : Limestone, Dolomite, Etc.
Dolomite: The aggregate consists of somewhat medium-grained dolomite and what appears to be relatively fine-grained dolomite with a fine-grained argillaceous/clayey matrix. The fine-grained dolomite appears textually similar to argillaceous dolomitic limestone, which is known to have caused ACR and (in recent studies) shown to have caused ASR.