Clay mineral transformations in podzolized tills in central Finland

Clay Minerals ◽  
1997 ◽  
Vol 32 (4) ◽  
pp. 531-544 ◽  
Author(s):  
D. Righi ◽  
M. L. Räisänen ◽  
F. Gillot

AbstractTransformations of clay minerals were studied in a sequence of podzols (Entic Cryorthods) of increasing age (5500-10000 years BP) developed from till materials in central Finland. The age of the soils was estimated according to altitude above the present sea level, with reference to the age of ancient shorelines and the rate of land uplift. Clay minerals in fine (<0.1 µm), coarse (0.1-2 µm) clay and fine silt (2-5 µm) fractions were studied by X-ray diffraction. The layer charge of expandable minerals was estimated on the basis of their re-expansion with ethylene glycol following K-saturation and heating to 110°C Pedogenic transformations of clay minerals occur essentially in the E horizons of the podzols. Smectites and illite-smectite mixed-layers are the dominant clay minerals in the E horizons of soils older than 6500 years. The number of mixed-layers decreases with evolution of the soil, leaving a nearly pure smectite phase in the oldest soil (10000 years). The smectites are dioctahedral with a tetrahedral charge. Groups of low-charge and highcharge interlayers are both present in the samples, but low-charge smectite layers were found only in the two older soils (9500-10000 years). This suggests alteration with time of the high-charge smectites.

Minerals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 970
Author(s):  
Maurício Dias da Silva ◽  
Márcia Elisa Boscato Gomes ◽  
André Sampaio Mexias ◽  
Manuel Pozo ◽  
Susan Martins Drago ◽  
...  

The object of this study is magnesian clay minerals present in carbonate rocks of the post-rift phase of the pre-salt in the Santos Basin. These rocks developed in an Aptian-age alkaline lacustrine environment. This study summarizes the formation of clay minerals associated with different lithotypes in a range of 19 m and a depth of more than 5100 m. They were characterized from petrographic analysis by optical microscopy, X-ray diffraction (total sample and clay fraction), and modeling by Newmod®; and examined and analyzed by scanning electron microscopy. An approach based on identifying lithotypes and characterization of microsites allowed us to understand the occurrence of different clay minerals. Kerolite was the most abundant mineral in the sampled range. It occurs in lamellar aggregates under greater preservation of the original rock lamination and in association with spherulites and shrubs. The Stv/Ker mixed layers occurs in the same association, and formed finer unlaminated aggregates associated with the more intense dolomitization and silicification processes. Saponite occurs associated with detrital minerals forming clayey levels intercalated with microcrystalline carbonates. Fluids with a high Mg/Si and pH < 9 favor the precipitation of kerolite. The increase in pH during diagenesis may be responsible for the formation of Stv/Ker mixed layers.


2016 ◽  
Vol 130 (4) ◽  
pp. 876-879
Author(s):  
F. García Tomás ◽  
M.A. Kojdecki ◽  
P. Pardo ◽  
R. Ibańez ◽  
A. Álvarez Larena ◽  
...  

1962 ◽  
Vol 42 (2) ◽  
pp. 296-301 ◽  
Author(s):  
J. S. Clark ◽  
J. E. Brydon ◽  
H. J. Hortie

X-ray diffraction analysis was used to identify the clay minerals present in fourteen subsoil samples that were selected to represent some more important clay-bearing deposits in British Columbia. The clay mineralogy of the subsoils varied considerably but montmorillonitic clay minerals tended to predominate in the water-laid deposits of the south and illite in the soil parent materials of the Interior Plains region of the northeastern part of the Province.


2014 ◽  
Vol 68 (8) ◽  
Author(s):  
Selvakumar Dhanasingh ◽  
Dharmaraj Nallasamy ◽  
Saravanan Padmanapan ◽  
Vinod Padaki

AbstractThe influence of cetyltrimethylammonium bromide and ethylene glycol on the size and dispersion of indium oxide nanoparticles prepared under hydrothermal conditions was investigated. The precursor compound, indium hydroxide, obtained by the hydrothermal method in the absence as well as the presence of cetyltrimethylammonium bromide, was converted to indium oxide by sintering at 400°C. The formation of nanoscale indium oxide upon sintering was ascertained by the characteristic infrared adsorption bands and X-ray diffraction patterns of indium oxide. Transmission electron microscopy and band gap values confirmed that the cetyltrimethylammonium bromide facilitated the formation of indium oxide nanoparticles smaller in size and narrower in distribution than those prepared without the assistance of cetyltrimethylammonium bromide.


1999 ◽  
Vol 79 (1) ◽  
pp. 103-109 ◽  
Author(s):  
F. Courchesne ◽  
J.-F. Laberge ◽  
A. Dufresne

The role of soil organic matter (OM) on SO4 retention was investigated by comparing OM content, SO4 retention, and the distribution of Fe, Al and Si compounds in OM-poor (Grands-Jardins, PGJ) and OM-rich (Hermine, HER) Podzols from Québec, Canada. At both sites, four pedons were sampled by horizon; soil pH in H2O, organic C, phosphate-extractable SO4 and, sodium pyrophosphate, acid ammonium oxalate and dithionite-citrate-bicarbonate (DCB) extractable Fe, Al and Si were measured for each mineral horizon. The mineralogy of the clay (<2 µm) and fine silt (2–20 µm) fractions of selected horizons was determined by X-ray diffraction (XRD) and infrared spectroscopy (IR). Weighted mean organic C and pyrophosphate extractable Fe and Al contents were significantly higher in the HER than in the PGJ sola, while the PGJ soils were richer in amorphous inorganic Al. No trends were observed for inorganic Fe compounds. Chemical dissolution and IR allowed the identification of short-range ordered aluminosilicates, probably allophane, in the OM-poor and slightly acidic to neutral PGJ soils. These materials were absent from the OM-rich and acidic HER soils. Phosphate extractions showed that the weighted mean native SO4 content was five times higher in the PGJ than in the HER soil. Finally, native SO4 was strongly related to inorganic Fe, Al and Si (associated with allophane) at PGJ but only to inorganic Fe at HER. These results indicate that OM indirectly affects SO4 sorption through the influence organic substances exerts on the nature and distribution of pedogenic Fe, Al and Si compounds, such as allophane, in Podzolic profiles. Key words: Organic matter, sulfate, imogolite, allophane, silica, Podzol


2021 ◽  
Vol 13 (2) ◽  
pp. 601-610
Author(s):  
K. Itiowe ◽  
R. Oghonyon ◽  
B. K. Kurah

The sediment of #3 Well of the Greater Ughelli Depobelt are represented by sand and shale intercalation. In this study, lithofacies analysis and X-ray diffraction technique were used to characterize the sediments from the well. The lithofacies analysis was based on the physical properties of the sediments encountered from the ditch cuttings.  Five lithofacies types of mainly sandstone, clayey sandstone, shaly sandstone, sandy shale and shale and 53 lithofacies zones were identified from 15 ft to 11295 ft. The result of the X-ray diffraction analysis identified that the following clay minerals – kaolinite, illite/muscovite, sepiolite, chlorite, calcite, dolomite; with kaolinite in greater percentage. The non-clay minerals include quartz, pyrite, anatase, gypsum, plagioclase, microcline, jarosite, barite and fluorite; with quartz having the highest percentage. Therefore, due to the high percentage of kaolinite in #3 well, the pore filing kaolinite may have more effect on the reservoir quality than illite/muscovite, chlorite and sepiolite. By considering the physical properties, homogenous and heterogeneous nature of the #3 Well, it would be concluded that #3 Well has some prospect for petroleum and gas exploration.


1999 ◽  
Vol 63 (6) ◽  
pp. 801-812 ◽  
Author(s):  
L. Quattropani ◽  
L. Charlet ◽  
H. de Lumley ◽  
M. Menu

AbstractBones from level G in the Arago cave (Tautavel, Southern France, 450 ky) were analysed using a combination of particle induced X-ray and gamma-ray emission (PIXE and PIGME) and X-ray diffraction (XRD). Human occupation and guano production by bats introduced a large amount of phosphate into the cave and as a result a decarbonated pocket was formed in the sediment, characterized by the dissolution of clay minerals, calcite and bones, and by the precipitation of phosphate secondary minerals. The Al released by clay minerals was reprecipitated as crandallite in the few remaining bones, and as montgomeryite with traces of crandallite in the surrounding sediments. Bones within the pocket have very high levels of Al, Fe, F and Zn and often have ‘diffusive’ type U-shaped concentration profiles. These profiles show that post-mortem uptake of trace elements occurred, and thus that trace element composition has to be used with care in palaeonutritional studies but is indicative of local palaeoenvironment. This uptake is complicated by a large increase in hydroxylapatite crystallinity in Palaeolithic bones compared to modern or more recent ones, as a result of the large P influx which occurred in the Arago cave after the sediment deposition.


2008 ◽  
Vol 8 (11) ◽  
pp. 5776-5780 ◽  
Author(s):  
C. Manikyala Rao ◽  
V. Sudarsan ◽  
R. S. Ningthoujam ◽  
U. K. Gautam ◽  
R. K. Vatsa ◽  
...  

ZnGa2O4 nanoparticles doped with lanthanide ions (Tb3+ and Eu3+) were prepared at a low temperature of 120 °C based on urea hydrolysis in ethylene glycol medium. X-ray diffraction studies have confirmed that strain associated with nanoparticles changes as Tb3+ gets incorporated in the ZnGa2O4 lattice. Based on steady state emission and excitation studies of ZnGa2O4:Tb nanoparticles, it has been inferred that ZnGa2O4 host is characterized by a broad emission around 427 nm and there exists energy transfer between the host and Tb3+ ions. Unlike this, for ZnGa2O4:Eu nanoparticles, very poor energy transfer between the host and Eu3+ ions is observed. These nanoparticles when coated with ligands like oleic acid results in their improved dispersion in organic solvents like chloroform and dichloromethane.


POSITRON ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 14
Author(s):  
Suci Aprilia ◽  
Erry Koryanti ◽  
Idha Royani

Telah dilakukan pembuatan molecular imprinted polymer (MIP) nano karbaril dengan metode cooling-heating. Pembuatan MIP nano karbaril bertujuan untuk mendapatkan material sensor yang potensial dalam aplikasinya. Dalam penelitian ini, bahan aktif karbaril di-milling dengan variasi waktu 10 menit dan 15 menit. Pada proses polimerisasi melibatkan templat nano karbaril, methacrylic acid (MAA) sebagai monomer fungsional, ethylene glycol dimathacrylate (EDMA) sebagai crosslinker, benzoil peroksida (BPO) sebagai inisiator, dan acetonitril sebagai pelarut yang disintesis menggunakan metode cooling-heating. Dengan cara yang sama, non-imprinted polymer (NIP) juga dibuat sebagai polimer kontrol.  NIP merupakan polimer yang dibuat dengan komposisi dan cara yang sama dengan MIP, namun tidak ditambahkan nano karbaril sebagai zat aktif. Pembuangan templat pada proses ekstraksi sangat berperan penting untuk menghasilkan material sensor yang baik. MIP, polimer, dan NIP yang dihasilkan di karakterisasi menggunakan Fourier transform infrared (FTIR) dan sampel terbaik dideteksi lebih lanjut dengan uji x-ray diffraction (X-RD), dan scanning electron microscope (SEM). Hasil FTIR menunjukkan bahwa gugus fungsi spesifik nano karbaril pada NIP tidak tampak bila dibandingkan dengan spektra MIP, dan terjadi penurunan persen transmitansi pada polimer dan peningkatan % transmitansi pada MIP. Hal ini menjelaskan bahwa terjadi penurunan konsentrasi nano karbaril pada MIP setelah proses ektraksi. Hasil X-RD menunjukkan ukuran kristal yaitu 9,16 Å. Hasil SEM menunjukkan bahwa jumlah pori tercetak dengan ukuran ≤100 nm yaitu 383 pori.  Data ini mengindikasikan bahwa MIP nano karbaril potensial untuk diaplikasikan sebagai material sensor.


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