Shale resistivity

Figure 4-330. Matthews and Kelly relationship between formation pore pressure and shale resistivity for the South Texas Gulf Coast. (Courtesy SPE [101]. ...

Another technique based on shale resistivity was proposed by Alixant [124]. This technique does not use a normal trend line or empirical correlations and is based solely on the shale resistivity. The procedure is as follows ... 

Example 26 Overpressure Detection with Shale Resistivity... 

A shale resistivity plot versus depth is shown in Figure 4-342 has been prepared with electric log data for a well drilled in south Louisiana. 

Figure 8.25 shows a comparison of the shale effect on the result of water saturation calculation. Input are the measured formation resistivity / t, the shale content Psh, the shale resistivity Rsh, the water resistivity the porosity (j), and the Archie parameters m,n. 

Shale properties (Rsh,BQy) Shale resistivity or shale conductivity in many practical applications is derived from the resistivity of an adjacent thick shale bed or by crossplot techniques. The property for the Waxman-Smits equation Bgv,CEC is subject of special core analysis measurements. 

Solution B Additional input is the shale resistivity / sh (derived from an adjacent thick shale layer). Then the sand resistivity and laminated shale content results ... 

Due to the small invasion and the large diameter of the sonde body, a resistivity near the true resistivity of the formation is generally measured. This is particularly true in shale where no invasion takes place. The main applications are ... 

Figure 4-294 shows a set of resistivity logs run in a sand-shale sequence of the Gulf Coast. We have one wireline dual induction log, one MWD resistivity log, a wiper-MWD resistivity log and one gamma ray log. 

In another example from Bourgoyne, the shale conductivity (inverse of resistivity) was plotted as shown in Figure 4-329 [101]. 

Figure 4-328. Example of resistivity decrease in overpressured shales.

Select a shale interval. Using MWD data, gamma ray, and resistivity, determine R.. 

Figure 4-341. Plot of the resistivity of shales versus depth in a Gulf Coast land well (Louisiana).

Brick Construction Brick-lined construction can be used for many severely corrosive conditions under which high alloys would fail. Brick linings can be installed over metal, concrete, and fiberglass structures. Acid-resistant bricks are made from carbon, red shale, or acid-resistant refractory materials. Red-shale brick is not used above 175°C (350°F) because of spalling. Acid-resistant refractories can be used up to 870°C (1600°F). See Table 25-10. 

The most imporant use of cobalt is in the manufacture of various wear-resistant and superalloys. Its alloys have shown high resistance to corrosion and oxidation at high temperatures. They are used in machine components. Also, certain alloys are used in desulfurization and hquefaction of coal and hydrocracking of crude oil shale. Cobalt catalysts are used in many industrial processes. Several cobalt salts have wide commercial apphcations (see individual salts). Cobalt oxide is used in glass to impart pink or blue color. Radioactive cobalt-60 is used in radiography and sterihzation of food. 

Silicon is the most important constituent of igneous and many sedimentary rocks, occurring in combination with oxygen in feldspars, micas, quartz, sands and shales. The element is used in electronic devices, while silicon in combination with oxygen as silica and silicates finds application in concrete, bricks, pottery, enamels, glasses, optical fibers for telecommunications, and refractory (high-temperature resistant) materials. 

Y-intercept and the slope, respectively, and are listed in Table I. The results of the dissolution rate determination method (method 2) are presented in Figure 3. As can be seen, the maximum removable mineral (P0) by dilute acid is independent of the size of the shale particles. However, the carbonate fraction in the shale mineral matrix is very close to this figure. This could mean that the accessibility of the leaching agent to the leachable materials in shale is complete in the size ranges studied in this experiment—but at different rates. This could also indicate that the carbonate deposit sites are not isolated but can, perhaps, be thought of as interconnected by minerals built of the dilute acid-resistant minerals. 

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