Barite cement

At the scale of thin sections, dissolution, cementation, and replacement are all prima facie evidence of elemental mobility. It is clear that late diagenesis involves complex history of material transfer at the scale of a few millimeters because detrital materials immediately adjacent to cements and grain replacements may show no evidence of dissolution, or contain no elements in common with the authigenic minerals. For minor elements that are concentrated in authigenic phases in amounts far in excess of their concentration in the bulk rock (e.g., barite cement), extraction from some relatively larger rock volume is necessary. 

Carbonates and Sulfates Carbonates include limestone, cal-cite, marble, marls, chalk, dolomite, and magnesite the most important sulfates are barite, celestite, anhydrite, and gypsum these are used as fillers in paint, paper, and rubber. (Gypsum and anhydrite are discussed below as part of the cement, lime, and gypsum industries.)... 

Stangen-blei, n. bar lead, -eiaen, n. bar iron, rod iron, -gold, n, ingot gold, -kali, n. potash in sticks, stick potash, -kitt, m. stick cement, -kupfer, n, bar copper, rod copper, -lack, m. stick-lac. -schwefel, m. roll sulfur, stick sulfur, cane brimstone, -seife, /. bar soap, -silber, n, ingot silver, -spat, m, columnar barite, -stahl, m. bar steel rod steel, -stein, m. pycnite (columnar topaz), -tabak, m. roll tobacco, -wachs, n. stick wax, stick polish, -zinn, n, bar tin. 

Apply cement squeeze or attapulgite gel-barite squeeze. 

Barite. This mineral additive requires much more water to be added to the cement slurry than does hematite. This large amount of added water required will decrease the compressive strength of the cement. This additive can be used to increase the specific weight of a cement slurry to as high as 19 Ib/gal. 

Weighting agents (Table 10-10) are added to increase the density of the cement. They are typically used to combat high bottom-hole pressures. Common additives are powdered iron, ferromat, powdered magnetite, and barite. Hematite ean be used to increase the density of a mixture up to 2200 kg/m (19 Ib/gal). Hematite requires the addition of some water. 

Ilmenite has a specific gravity of 4700 kg/m. It requires no addition of water when added to the slurry. Ilmenite has a minimal effect on the thickening time and compressive strength. Barite requires more water then hematite when added to the cement. This results in a decrease of the compressive strength of the set cement. 

Other types of cements include anhydrite, barite, pyrite, iron hydroxides haematite, albite and apatite and are subordinate. 

Sandstone - [CEMENT] (Vol 5) -barite m [BARIUM COMPOUNDS] (Vol 3) -uranium m [NUCLEARREACTORS - NUCLEAR FUEL RESERVES] (Vol 17)... 

Barite occurs as scarce, large crystals (up to 2 mm) filling vugs and cracks and engulfing as well as replacing kaolinite and carbonate cements in dolocretes and calcretes (Fig. 14F). In the sandstones, barite occurs as a few poikilotopic and small crystals which cover, and thus postdate, chlorite rims around framework grains. 

Barite occurs in trace amounts as patchy poikilo-topic, grain-replacive cement associated with partially dissolved carbonate cement. Anhydrite cement forms < 1 vol% in the fine- to medium-grained sandstones that contain micritic carbonate intraclasts (calcretes/dolocretes), occurring in the upper part of... 

In the Furado area there was no interruption in burial conditions caused by post-rift uplift, and the reservoirs remained at similar depths during this phase. Therefore, it is uncertain whether or not the mesogenetic constituents were precipitated during syn-rift or post-rift phases. Some C2 calcite, which engulfed and thus post-dated albite, chlorite, illite, quartz and trace amounts of pyrite, barite and sphalerite, is interpreted to have precipitated during this time interval. This C2 calcite is characterized by a chemical and isotopic composition similar to the carbonate cements formed during the syn-rift subsidence phase. 

Authigenic K-feldspar is present in the Gurten samples as thin overgrowths on detrital K-feldspar grains. Quartz cement was found only in the SEM in two samples from Altishofen. Sulphates (barite. 

Bentonite or other clays are added to the mud if there are not enough clays or solids present. Fibrous materials such as special cements, sawdust, beet pulp, cellophane and shredded plastic foil may be used as a seal. High-density fluids are used to prevent blowouts, and weighting materials, such as barite, may be added to increase the weight of the mud for deep drilling. 

Hydrauhc cements are used to coat pipe inside and outside, especially pipes that are to be buried or submerged, for example, water or sewer lines. In the case of underwater piping to transport gas or hquid hydrocarbons, for example, it may be mixed with barites or other heavy materials to confer negative buoyancy. It also may be used in mixtures of organic materials where its ability to maintain a noncorrosive pH at the surface of steel is exploited. 

The waste will be conditioned with cement inside baritic concrete containers. The containers have the shape of an octagonal prism, their overall length is 4.6 m, the maximum external diameter is 2.1 m and the final weight of each container after the waste conditioning will be about 50 ton. 

Blue spiral stripe—potable water Brown spiral stripe—diesel Yellow longitudinal stripe—base oil Orange longitudinal stripe—oil-based mud Red spiral stripe—brine mud/brine Green spiral stripe—cement Orange spiral stripe—bentonite or barite... 

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