clay mineralogy
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CATENA ◽  
2022 ◽  
Vol 211 ◽  
pp. 106009
Author(s):  
Thaís Nascimento Pessoa ◽  
Paulo Leonel Libardi

Author(s):  
Golnaz Jozanikohan ◽  
Mohsen Nosrati Abarghooei

AbstractThe complete characteristics knowledge of clay minerals is necessary in the evaluation studies of hydrocarbon reservoirs. Ten samples taken from two wells in a heterogeneous clastic gas reservoir formation in NE Iran were selected to conduct the transmission Fourier transform infrared spectroscopy (FTIR) tests for the clay mineralogy studies. The FTIR analysis showed that there were clear signs of clay minerals in all samples. The wavenumber region of the clay minerals in FTIR tests was detected to be 3621, 3432, 1034, and 515 cm−1 for illite, 3567, 3432, 1613, 1088, 990, 687, 651, and 515 cm−1 for magnesium-rich chlorite, 3700, 3621, 3432, 1034, 687, and 463 cm−1 for kaolinite, and 3567, 1088, 990, and 463 cm−1 for glauconite. After screening of samples by the FTIR method, the samples were then analyzed by powder X-ray diffraction (PXRD), wavelength dispersive X-ray fluorescence (WDXRF), and scanning electron microscopy (SEM). The PXRD and SEM result showed illite was by far the most common clay present. Kaolinite, magnesium-rich chlorite, and traces of smectite and the mixed-layer clays of both the illite–smectite and chlorite-smectite types were also recognized. The combination of PXRD and WDXRF results could quantify the clay abundances in the each well too. It was concluded that the FTIR analysis successfully could show the absorption bonds of all constituent clays. However, the infrared absorption spectra of mixed-layer clays overlapped those of the respective constituents of each mixed-layer minerals. This can be considered as the evidence of the usefulness of FTIR technique in the screening of the samples for the clay mineralogy studies.


Clay Minerals ◽  
2022 ◽  
pp. 1-47
Author(s):  
Georgia Leontopoulou ◽  
Georgios E. Christidis ◽  
Grigorios Rousakis ◽  
Noémi S. Müller ◽  
George Papatheodorou ◽  
...  

Soil Systems ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Bradley E. Suther ◽  
David S. Leigh ◽  
Larry T. West

Temporal changes in soil development were assessed on fluvial terraces of the Little River in the upper Coastal Plain of North Carolina. We examined five profiles from each of six surfaces spanning about 100,000 years. Soil-age relationships were evaluated with inter-surface clay mineral comparisons and regression of chemical properties versus previously reported optically-stimulated luminescence ages using the most developed subsoil horizon per profile. Bases to alumina (Bases/Al2O3) ratios have negative correlations with age, whereas dithionite-Fe (FeD) concentrations are positively correlated with time and differentiate floodplain (<200 yr BP) from terrace (≥10 ± 2 ka) soils and T4 pedons (75 ± 10 ka) from younger (T1-T3b, 10 ± 2–55 ± 15 ka) and older (T5b, 94 ± 16 ka) profiles. Entisols develop into Ultisols with exponentially decreasing Bases/Al2O3 ratios, reflecting rapid weatherable mineral depletion and alumina enrichment during argillic horizon development in the first 13–21 kyr of pedogenesis. Increasing FeD represents transformation and illuviation of free Fe inherited from parent sediments. Within ~80–110 kyr, a mixed clay mineral assemblage becomes dominated by kaolinite and gibbsite. Argillic horizons form by illuviation, secondary mineral transformations, and potentially, a bioturbation-translocation mechanism, in which clays distributed within generally sandy deposits are transported to surface horizons by ants and termites and later illuviated to subsoils. T5b profiles have FeD concentrations similar to, and gibbsite abundances greater than, those of pedons on 0.6–1.6 Ma terraces along Coastal Plain rivers that also drain the Appalachian Piedmont. This is likely because the greater permeability and lower weatherable mineral contents of sandy, Coastal Plain-sourced Little River alluvium favor more rapid weathering, gibbsite formation, and Fe translocation than the finer-grained, mineralogically mixed sediments of Piedmont-draining rivers. Therefore, recognizing provenance-related textural and mineralogical distinctions is crucial for evaluating regional chronosequences.


Author(s):  
Maame E. T. Croffie ◽  
Paul N. Williams ◽  
Owen Fenton ◽  
Anna Fenelon ◽  
Karen Daly

Abstract Purpose Information about particle size distribution (PSD) and soil texture is essential for understanding soil drainage, porosity, nutrient availability, and trafficability. The sieve-pipette/gravimetric method traditionally used for particle size analysis is labour-intensive and resource-intensive. X-ray fluorescence (XRF) spectrometry may provide a rapid alternative. The study’s aim was to examine the use of XRF for rapid determination of PSD in Irish soils. Methods Soils (n = 355) from existing archives in Ireland were analysed with a benchtop energy-dispersive XRF (EDXRF). Correlation and regression analyses were determined to compare Rb, Fe, Al, and Si concentrations to % clay, % silt, and % sand. Also, linear regression models were developed to compare % clay, % sand, and % silt measured by the gravimetric method to values predicted by EDXRF. Results The relationship between element concentration and PSD was dependent on parent material. Rb, Al, and Fe showed a significant (p < 0.05) correlation (r > 0.50) with % clay and % sand in soils derived from limestone and siliceous stone parent materials. Rb was the best predictor for % clay (R2 = 0.49, RMSE = 10.20) in soils derived from limestone and siliceous stone-derived soils. Conclusion Geochemistry and clay mineralogy of the soils’ parent material strongly influenced the EDXRF’s ability to predict particle size. The EDXRF could predict % clay in soils from parent materials which weather easily, but the opposite was true for soils with parent material recalcitrant to weathering. In conclusion, this study has shown that the EDXRF can screen % clay in soils derived from limestone and siliceous stone parent materials.


2021 ◽  
Vol 49 (3) ◽  
pp. 351
Author(s):  
P. Gowthamy ◽  
S.P. Indraratne ◽  
R. Weerasooriya ◽  
R.B. Mapa

2021 ◽  
Vol 54 (12) ◽  
pp. 1783-1794
Author(s):  
R. V. Desyatkin ◽  
S. N. Lessovaia ◽  
M. V. Okoneshnikova ◽  
A. Z. Ivanova

Abstract— Data on major properties and clay mineralogy in the profiles of slightly differentiated Cryosols forming in cold ultracontinental climate of Yakutia are discussed. The particular objects are represented by the cryozems of tundra, forest-tundra, and northern taiga of the Anabar and Alazeya plateaus and by the palevaya (pale) soil of middle taiga in Central Yakutia. The differentiation of clay minerals in the vertical soil profiles is poorly pronounced because of the strong homogenizing impact of cryoturbation processes. The profile of pale soil displays minor differences in clay mineralogy despite the strong difference in acid–base conditions of the upper and lower horizons. However, the obtained data suggest that mineral weathering in pale soils of Central Yakutia is more advanced than it was concluded in the 1970s on the basis of data on the absence of pronounced trends in the vertical distribution of clay minerals in their profiles. This is in good agreement with the presence of a sufficiently thick upper humus horizon in these soils, which is typical of the soils of more humid regions. It is suggested that pale soils of Central Yakutia should be classified as soddy pale soils.


2021 ◽  
Vol 6 (10) ◽  
pp. 363-375
Author(s):  
M. S. Mohamed ◽  
Shimaa A.M. Amer ◽  
G. A. Abdel-Kader
Keyword(s):  

2021 ◽  
Author(s):  
Mengyang You ◽  
Xia Zhu-Barker ◽  
Timothy A. Doane ◽  
William R. Horwath

AbstractThe interaction of organic carbon (OC) with clay and metals stabilizes soil carbon (C), but the influence of specific clay-metal-OC assemblages (flocs) needs further evaluation. This study aimed to investigate the stability of flocs in soil as affected by external C inputs. Flocs representing OC-mineral soil fractions were synthesized using dissolved organic C (DOC) combined with kaolinite (1:1 layer structure) or montmorillonite (2:1 layer structure) clays in the absence or presence of two levels of Fe (III) (named low or high Fe). Flocs were mixed with soil (classified as Luvisol) and incubated with or without 13C labelled plant residue (i.e., ryegrass) for 30 days. The CO2 emissions and DOC concentrations as well as their 13C signatures from all treatments were examined. Total C mineralization from flocs was approximately 70% lower than non-flocced DOC. The flocs made with montmorillonite had 16–43% lower C mineralization rate than those made with kaolinite with no Fe or low Fe. However, when flocs were made with high Fe, clay mineralogy did not significantly affect total C mineralization. A positive priming effect (PE) of flocs on native soil OC was observed in all treatments, with a stronger PE found in lower Fe treatments. The high-Fe clay flocs inhibited ryegrass decomposition, while the flocs made without clay had no impact on it. Interestingly, flocs significantly decreased the PE of ryegrass on native soil OC decomposition. These results indicate that the adsorption of DOC onto clay minerals in the presence of Fe (III) stabilizes it against decomposition processes and its stability increases as Fe in flocs increases. Flocs also protect soil OC from the PE of external degradable plant C input. This study showed that Fe level and clay mineralogy play an important role in controlling soil C stability.


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