Chemistry of illite-smectite inferred from TEM measurements of fundamental particles

Środoń, J.; Elsass, Françoise; McHardy, W. J.; Morgan, David

doi:10.1180/claymin.1992.027.2.01

Cited by 171 publications

(17 citation statements)

References 25 publications

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“…The heterogeneity of the original smectite [23] would determine a faster process in R0, whereas the heterogeneity would be lower in the R1 stage due to the prior smectite transformation to R1. In addition, the results (Figure 4a) indicate that the smectite layer charge increases up to an approximate mean value of 0.40/O 10 (OH) 2 , which is similar to the maximum charge values obtained for the I/S smectite layers by other authors using different methods [55,57,58].…”

Section: Evolution Of the Layer Charge During Diagenesissupporting

confidence: 87%

Evolution of Clays in Cretaceous Marly Series (Álava Block, Basque Cantabrian Basin, Spain): Diagenesis and Detrital Input Control

et al. 2019

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Two stratigraphic sections of carbonate sediments with significant thickness differences and without appreciable tectonic deformation were studied near the trough and on a threshold zone at the Álava Trough. Such characteristics make them appropriate to analyze the influence of a slow progression of the diagenesis over the original clay suite. X Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Analytical Electron Microscopy (AEM) techniques were applied in natural and alkylammonium-treated samples. Diagenesis slightly modified the clay mineralogy, the disappearance of smectite, and the variation in the content and ordering of the I/S mixed layer, with burial being the most noteworthy process. The total charge in the 2:1 expandable layers of smectite and I/S shows a slight increase, preferentially located on tetrahedral sheets, with depth. The data suggest a moderate diagenesis grade for the studied materials. The combination of techniques allowed identification of several types of detrital micaceous phases, as well-crystallized K-rich micas, Na-K micas, mica-chlorite stacks, and illites, with an expandable behaviour after the alkylammonium treatment. The total charge of illites did not change with diagenesis, suggesting their detrital origin. This research shows that the detrital assemblage masks the diagenetic evolution in the basin, which indicates the importance of the combination of different techniques to infer correctly the diagenetic grade in a sedimentary basin.

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Section: Evolution Of the Layer Charge During Diagenesissupporting

confidence: 87%

Evolution of Clays in Cretaceous Marly Series (Álava Block, Basque Cantabrian Basin, Spain): Diagenesis and Detrital Input Control

et al. 2019

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“…Previous studies of monomineralic illites and I-S formed by diagenetic and hydrothermal alteration of pyroclastic deposits found that the content of fixed K + in illite is 0.90 per O 10 (OH) 2 (Meunier and Velde 1989;Ś rodoń et al 1992;Sakharov et al 1999). Accordingly, Ś rodoń et al (1992) assumed that this K 2 O can be used for calculating the mean thickness of illitic fundamental particles.…”

Section: Content Of Fixed K In Illite I-s and I-t-smentioning

confidence: 96%

Illite-smectite structural changes during metamorphism in black Cambrian Alum shales from the Baltic area

Lindgreen

Drits

Sakharov

et al. 2000

American Mineralogist

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Illite-smectite (I-S) from Cambrian black shale of both early diagenetic and anchimetamorphic grade was investigated to determine the mechanism of the clay transformation. The layer sequences, the distribution of thicknesses of coherent scattering domains (CSDs), and the three-dimensional ordering were determined by X-ray diffraction (XRD). The proportions of cis-vacant (cv) and transvacant (tv) 2:1 layers were determined by thermal analysis and the proportion and distribution of interlayer ammonium by XRD and by infared spectroscopy (IR). The structural formulae were determined from total chemical analysis, and Mössbauer and 27 Al NMR spectroscopies, and the particle shape and size investigated by atomic force microscopy (AFM). In the early diagenetic samples, the I-S is composed of two phases, one of which contains 0.05 and the other 0.25 smectite (S) interlayers. The first phase does not change during metamorphism. In the second phase, 0.20 S are converted to tobelite (T) layers through fixation of NH 4 + , but the I layers are not changed. Simultaneously, the proportion of cv layers changes from 0.18 to 0.02, and the tetrahedral substitution of Al for Si is parallel to the increase in T layers. All I interlayers contain 0.75K per O 10 (OH) 2 . Furthermore, the metamorphism results in increasing mean thickness of CSDs from 5.1-6.8 nm for the lowdiagenetic samples to 6.7-8.4 nm for the anchimetamorphic samples. We conclude that the tobelitization was accompanied by transformation of cv to tv 2:1 layers adjacent to the smectite interlayers, and formation of tv layers adjacent to the newformed tobelite interlayers in otherwise intact crystallites. This mechanism only partly resembles the tobelitization previously observed in the Upper Jurassic North Sea oil source rocks. I-S in these rocks contained tv 2:1 layers and T interlayers formed through solid-state Al for Si substitution in the tetrahedral sheet and by ammonium fixation in the corresponding interlayers. These different mechanisms are probably because the North Sea I-S originated from weathered illite, like the Cambrian high-illitic phase, whereas the Cambrian low-illitic phase undergoing the transformation originated from cv smectite of volcanic origin. The results indicate that the illitization in oil source rocks is linked to oil generation, and that it deviates from the illitization in other rocks because of the supply of ammonium formed during oil generation and the fixation of this ammonium in the former smectite interlayers.*

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“…A random walk model of Hall et al (2000) The illite-smectite crystallites commonly have thicknesses of their fundamental illite particles from two to several 2:1 layers (Nadeau et al, 1984;Środoń et al, 1992;Dudek et al, 2002). If the 40 Ar recoil energy can make some 40 Ar atoms penetrate through a single 2:1 layer, the broadly accepted assumption that all radiogenic 40 Ar remains mechanically trapped in the interlayer may be incorrect.…”

Section: Introductionmentioning

confidence: 99%

Molecular modeling of the effects of 40Ar recoil in illite particles on their K–Ar isotope dating

Szczerba

Derkowski

Kalinichev

et al. 2015

Geochimica et Cosmochimica Acta

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Chemistry of illite-smectite inferred from TEM measurements of fundamental particles

Cited by 171 publications

References 25 publications

Evolution of Clays in Cretaceous Marly Series (Álava Block, Basque Cantabrian Basin, Spain): Diagenesis and Detrital Input Control

Evolution of Clays in Cretaceous Marly Series (Álava Block, Basque Cantabrian Basin, Spain): Diagenesis and Detrital Input Control

Illite-smectite structural changes during metamorphism in black Cambrian Alum shales from the Baltic area

Molecular modeling of the effects of 40Ar recoil in illite particles on their K–Ar isotope dating

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