Albite diagenetic

Two phase assemblages of any of these minerals are known. It should be noted that aluminous phases, such as kaolinite, have never been reported with corrensite neither are sedimentary phyllosilicates such as 7 8 chlorite or glauconite. Non-phyllosilicates in association with corrensite frequently include diagenetic quartz, albite and dolomite. Pelitic rocks, specially associated with those containing corrensite, contain allevardite and fully expanding montmorillonite (dioctahedral). 

A wide variety of zeolites are known to form in saline lakes where the species present is dependent upon the chemistry of the solutions. Rapid zeolite formation is aided by the existence of the volcanic glass and high water salinities. Potassium feldspar occurs with the common alkali zeolites (Hay and Moiola, 1963 Hay, 1964 Hay, 1966 Sheppard and Gude, 1969, 1971), however, albite is not evident as a diagenetic mineral in saline lakes. 

The second division of the zeolite facies is based upon the appearance of albite as a diagenetic mineral, usually coexisting with analcite in the initial stages of its development, and also with the widespread development of montmorillonite-illite mixed layered mineral (30 to 90% expandable layers) coexisting with illite. The phase relations of this facies are indicated by Figure 35b. Assemblages can contain natrolite as above. They are ... 

Even detrital or authigenic minerals in bulk equilibrium under some specific diagenetic condition (e.g., detrital albite in contact with albite-saturated water) may still be at disequilibrium with respect to their trace element and isotopic composition, as weU as their structural state. Such disequilibrium favors dissolution, even if fluids are near equilibrium with respect to the bulk mineral. 

Aagaard P., Egeberg P. K., Saigal G. C., Morad S., and Bj0rlykke K. (1990) Diagenetic albitization of detrital K-feldspars in Jurassic, Lower Cretaceous, and Tertiary clastic reservoir rocks from offshore Norway 11. Formation water chemistry and kinetic considerations. J. Sedim. Petrol. 60, 575-581. 

Helmold K. P. and van de Kamp P. C. (1984) Diagenetic mineralogy and controls on albitization and laumontite formation in Paleogene arkoses, Santa Ynez Mountains, Cahfomia. In Clastic Diagenesis (eds. D. A. McDonald and R. C. Surdam). American Association of Petroleum Geologists, Tulsa, OK, vol. 37, pp. 239—276. 

Walker T. R. (1984) Diagenetic albitization of potassium feldspar in arkosic sandstones. J. Sediment. Petrol. 54,3-16. 

Fig. 7. Present and original detrital composition of representative Lunde sandstones plotted on McBride s (1963) diagram A, considering albitized feldspars as diagenetic constituents (not in F pole)—observe the shift from the arkose (original composition white dots) to the subarkose field (present composition black dots) B, plotting albitized feldspars in F pole—a less substantial field dislocation is seen from original (white squares) to present composition (black squares).

On average, diagenetic albite replaced 6.2 bulk rock-volume %, corresponding to a 2/5 of the detri-... 

Together with calcite, other diagenetic features of the Namorado Sandstone include dolomite, opal, kaolinite, K-feldspar overgrowths, chlorite, albite, anatase, barite, pyrite and pseudomatrix generated by squeezing of clay clasts. The whole diagenetic evolution is detailed by Carvalho (1990), Abreu et al. (1992) and Carvalho et al. (1995). 

Vandergrift GF, Winans RE, Scott RG, Horwitz EP (1980) Quantitative study of the carboxylic acids in Green River oil shale bitumen. Fuel 59 627-633 Walker TR (1984) Diagenetic albitization of potassium feldspar in arkosic sandstones. J Sediment Petrol 54 3-16... 

Franklin (1991) found that both acetate and oxalate significantly increased albite solubility at temperatures, pressures, and pH values (4.6-4.7) that may exist under diagenetic conditions. For example, aluminum reached a steady-state concentration of 13 ppm in the acetate buffer solution, essentially identical to that observed by Reed (1990) in acetic acid at the same pH (4.7) and total acetate concentration. Dissolved aluminum was even higher in the acetate-oxalate solution (pHf = 4.6) reaching a steady-state concentration of 48 ppm (Fig. 2), whereas aluminum concentrations in distilled water and the C02-water solution were high concentrations of aluminum in the acetate-oxalate solution did not vary substantially with flow rate and were maintained for pore-fluid residence times of up to 3... 

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