Minerals smectite

Main gangue minerals of the Se-type deposits comprise quartz, adularia, illite/ smectite interstratified mixed layer clay mineral, chlorite/smectite interstratified mixed layer clay mineral, smectite, calcite, Mn-carbonates, manganoan caleite, rhodoehrosite, Mn-silicates (inesite, johannsenite) and Ca-silicates (xonotlite, truscottite). 

In the Se-type gangue minerals comprise quartz, adularia, illite/smectite inter-stratified mixed layer clay mineral, smectite, calcite, Mn carbonates (manganoan calcite, rhodochrosite), Mn silicates (inesite, johansenite) and Ca silicates (xonotlite, truscottite). In comparison, the Te-type contains fine-grained, chalcedonic quartz, sericite, barite, adularia and chlorite/smectite interstratified mixed layer clay mineral. Carbonates and Mn minerals are very poor in the Te-type and they do not coexist with Te minerals. Carbonates are abundant and barite is absent in the Se-type. Grain size of quartz in the Te-type is very fine, while large quartz crystals are common in the Se-type. 

Giese et al. [48] have compiled a list of y+ and y values for a variety of clay minerals. Smectites, vermiculites, and micas tend to be very hydrophilic, with y > 28mJ/m2 and with a sizable electron acceptor parameter as well (y+ > 1 mJ/m2). Illites, on the other hand, were reported to be moderately hydrophobic (y varied from 14 to 19mJ/m2) and tended to have y+ — 0. 

Weathering continues after the formation of secondary minerals because the secondary minerals are stable only between certain concentration limits of soluble silica, alkali and alkaline earth cations, and H+ in the soil solution. As these solutes are leached away, the concentration changes make the initial secondary minerals (smectites, calcite, gypsum, etc.) unstable. As weathering progresses, these intermediate minerals weather further to still more stable chemical states. 

For rocks of ground surface, the water-rock interaction is frequent, the content of chlorite, illite and quartz are higher than the drilling rock. Feldspar and dolomite disapper, while the clay minerals smectite is appearing.The deep rock have poor environment of water-rock interaction. Besides, point load of ground rock is lower than... 

Other important characterization studies are ion-exchange capacity, especially cationic, and specific surface measurement. CEC is an important parameter in clay characterization and soil behavior, because it affects nutrient availability, among other soil properties. Some clay minerals (smectites and vermiculites) have a high... 

One of the recent successes in computCT simulation of clay mina-al hydrates is that the structure of interlayer wate in toms of quantitatively obtainable content called total radial distributionfunction was achieved by both Monte Carlo simulations and neutron diffraction methods (111,112). The accuracy of the method and the predicting power of the molecular simulation of this complex solid-liquid interface was first confirmed for the intolayCT structure of 2 1 clay mineral smectite. Computational studies on the clay mina-al-water interface using quantum mechanics, molecular mechanics, Monte Carlo, and molecular dynamics simulations are summarized in Table 5. 

Garn, P. D., 1965. Thermoanalytical Methods of Investigation. New York Academic Press. Greene-Kelly, R., 1957. The montmorillonite minerals (smectites). In The Differential Thermal Investigation of Clays. R. C. Mackenzie, ed. London Mineralogical Society, p. 140. 

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