Clayey shale

The natural moisture content of shales varies from less than 5%, increasing to as high as 35% for some clayey shales (Table 5.31). When the natural moisture content of shales exceeds 20%, they frequently are suspect as they tend to develop potentially high pore water pressures. Usually, the moisture content in the weathered zone is higher than in the unweathered shale beneath. Depending on the relative humidity, many shales slake almost immediately when exposed to air. Desiccation of shale following exposure leads to the creation of... 

Quartz-free clayey shale was taken from the surrounding strata of Erda seam, Fiirst Leopold-Baldur mine at Harvest-Dorsten. The fraction <5 un according to Robock and KlosterkOtter mainly contains crystalline kaolinite. It was pressed to square bars and re-dispersed in Polley s (1963, 1965) dust channel 4 h per day, 5 days per week. 

Fig. 90. Oedema in a Clara cell of a bronchiole (block S2) from a female rat (breeder Winkelmann, Borchen-Kirchborchen) which had inhaled 20 mg quartz-free clayey shale dust/m (particles less than 5 /

Near Viiivela, in Malaga, native antimony is found to be impr nated in the clayey shales, the size of the impregnated masses vary ing from that of an egg down to minute spangles. 

The technique has been tried in various areas of the world with good results provided that the shales are very clayey. Silt, sand or carbonates will lead to erroneous results. Figure 4-332 is an example of calculation in a North Sea well. 

In the boreholes, which are placed at a parking lot, single U-pipes are installed. There is no back filling, but the holes are filled with ground water. The boreholes are drilled through 65 m of clayey soil and 135 m of shale. The thermal conductivity has been measured with a Thermal Response Test (TRT) to be approx. 2.8 W/m K. 

Table 3 lists examples of more than a dozen different chemical types of river water. Although Ca and HCO j" are generally dominant, Mg dominance over Ca + can be found in rivers draining various lithologies such as basalt, peridotite, serpentinite, dolomite, coal, or where hydro-thermal influence is important (Semliki). Sodium may dominate in sandstone basins, in black shales (Powder, Redwater in Montana), in evaporitic sedimentary basins (Salt), in evaporated basins (Saoura), and where hydrothermal and volcanic influence is important (Semliki, Tokaanu). rarely exceeds 4% of cations, except in some clayey sands, mica schists, and trachyandesite it exceeds 15% in extremely dilute waters of Central Amazonia and in highly mineralized waters of rift lake outlets (Semliki, Ruzizi). 

Bearpaw Formation dark-grey blocky shale and silty shale, greenish glauconitic and grey clayey sandstone thin concretionary ironstone and bentonite beds, marine (Green, 1972)... 

The project was a reinforced concrete (R.C.) bridge over a river in Selangor, Malaysia. The proposed heights of the approach embankments on both sides of the abutments were about 8 m with side slope of 1F (vertical) to. 5H (horizontal). These embankments were to be constructed over a layer of very soft silty clay or clayey silt of 3 m to 9 m thick with Standard Penetration Tests values SPT) N of zero. Underlying the very soft top layer was 3.5 m to 5.5 m thick of medium dense silty sand followed by completely weathered shale with SPT W values varying between 30 to 50 blows/300mm. The liquid limit (w/) of the clay was about 78% and average moisture content was about 106%. 

Raw feed from the southwestern U.S., said to be unusually easy to burn, contains a clayey microcrystalline limestone and shale. The feed has only 3.2% retained on the 125-pm screen, with 15.2% >45 pm, and has <1.0% acetic-acid insoluble residue >45 pm, the latter composed of ordinary quartz with minor amounts of glauconite (a complex alkali-caldum-iron-magne-sium aluminosilicate). Belite nests are scarce and relatively small isolated belite is abundant. The clinker is finely crystalline, easily ground, and produces a high strength mortar (typically greater than 49 MPa). 

Argillaceous ar-j9- la-sh9s (ca. 1731) adj. Composed primarily of clay or shale clayey. 

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