Formation de phyllosilicates dans les roches carbonatées cristallines de La Mauricie, Québec

1989 ◽  
Vol 26 (7) ◽  
pp. 1463-1473
Author(s):  
Christian de Kimpe

The chemical and mineralogical analyses of the disaggregated material collected in the fracture planes of crystalline carbonate outcrops at three sites north of Trois-Rivières, Quebec, showed the formation of expanding phyllosilicates, smectite and vermiculite, mainly at the expense of the ferromagnesian minerals hornblende and augite. The clay minerals are enriched in Fe and Mg with respect to the parent material composition and are associated with the crystalline Fe oxides goethite and lepidocrocite. The moderate to low degree of mineral transformation is accounted for by the slow dissolution of the carbonates. Corrensite, a regularly interstratified clay mineral, was identified in 50% of the samples; it probably resulted from the hydrothermal alteration of phlogopite. Silicate alteration may have been responsible for a fraction of the swelling minerals found in the soils of the area.

Clay Minerals ◽  
2002 ◽  
Vol 37 (4) ◽  
pp. 699-707 ◽  
Author(s):  
A. Mirabella ◽  
M. Egli ◽  
S. Carnicelli ◽  
G. Sartori

AbstractThe formation of clay minerals was investigated in Spodosols developed in the subalpine belt, with similar exposure, climate and age, but deriving from different parent materials. All the soils were classified as Haplic Podzols and showed the characteristic eluviation and illuviation features of Fe, Al and organic carbon. However, varying parent material lithology led to different clay mineral assemblages in the soil. Smectite could be found in the E horizons of soils developed from granodiorite and tonalite materials. Its formation was strongly dependent on the presence of chlorite in the parent material. If nearly no other 2:1 mineral components, such as chlorite, are present in the lower soil horizons, then a residual micaceous mineral becomes the dominant clay mineral. The latter derives from a mica-vermiculite interstratified mineral.


Clay Minerals ◽  
1984 ◽  
Vol 19 (4) ◽  
pp. 579-590 ◽  
Author(s):  
Tj. Peters ◽  
B. Hofmann

AbstractClay minerals of several hydrothermally altered zones in a 1200-m biotite-granite core from a drillhole in northern Switzerland were studied microscopically, by XRD and by electron microprobe. The minerals principally affected by the hydrothermal alteration were plagioclase (An5-An20) and, to a lesser extent, biotite. Illite, regularly interstratified illite-smectite and dioctahedral chlorite-smectite, dioctahedral chlorite, trioctahedral chlorite and kaolinite were detected in the alteration products. Commonly, two or more clay minerals occurred together in pseudomorphs after plagioclase. The mineral chemistry of the clay minerals showed a predominance of the substitution KAl for Si and, to a lesser extent, MgSi for Al. Fluid-inclusion data and the absence of pure smectite and epidote indicated temperatures of ∼200°C for the fluid that caused this alteration.


Controversy regarding the age and character of mineralization in the northern Pennine orefield is reviewed in the context of recent geological and geochronological research in the region, and a number of the unresolved problems are tabulated. A new method of potassium-argon radioisotopic age determination which utilizes the conversion of the natural isotope 39 K in a rock or mineral to the isotope 39 Ar by neutron irradi­ation is described in outline. This method avoids some of the limitations of conventional potassium-argon age determination, and, among other advantages, makes the measurement of the radioages of clay minerals possible. A geochronological and petrological investigation of White Whin samples from the northern Pennine orefield is reported in full, and eighteen new age determinations, mostly upon clay mineral concentrates are presented. The conclusions that can be drawn from this work support a hypothesis of repeated hydrothermal mineralizations within the area of the northern Pennine orefield: the first within the period 284 ± 40 My with subsequent maxima of hydrothermal activity occurring at intervals. At least two of these subsequent episodes have been identified: one around a minimum age of 230 My and another, very important episode occurring around 170 My. Comparison of these results with histograms of (1) all radio­ages of British rocks and (2) radioages from British dolerites and basalts only, suggests that episodic hydrothermal alteration of pre-existing rocks may be a widespread phenomenon in Britain.


1990 ◽  
Vol 12 (12) ◽  
pp. 111
Author(s):  
Rejane Maria Scopel ◽  
Milton Luiz Laquintinie Formoso ◽  
Alain Meurnier ◽  
Patrick Dudoignon

Clay minerals, zeolites, calcite and silica (quartz, opal and chalcedony) are the most common hydrothermal alteration products of the basalts with veins in São Gabriel (Planalto) Region. The petrographic and geochemical studies led to the identification of the secondary phases which fill the veins. From the border to the centre, the filling of the veins comprises: a) brown clay mineral (ferri-montmorillonite), b) prismatic zeolite (heulandite) and/or fibro-radiated saponite/chlorite, and c) interstratiphied saponite/chlorite.


2016 ◽  
Vol 1 (1) ◽  
pp. 19 ◽  
Author(s):  
Dwi Winarti ◽  
Dwikorita Karnawati ◽  
Hary Christady Hardiyatmo ◽  
Srijono Srijono

Debris slides were recently found in the Pelangan area at Southern Mountain of Lombok Island, Indonesia. Pelangan is well known as the gold mineralization and hydrothermal alteration area. This study is aimed to identify the mineralogy and geochemistry of altered andesitic tuff that controlled slope instability and induced debris slides. For this purpose, it is necessary to prepare the field observation and laboratory analyses. Landslide inventory reveals that the Pelangan debris slides mostly occur in altered andesitic tuff. Based on the outcrop observations in the field, andesitic tuff found around the Pelangan debris slides have been altered in general. The strong intensity of alteration developed by hydrothermal alteration in this study area produces large amount of clay minerals especially montmorillonite, kaolinite, and illite. The abundance of those clay minerals reflect the intermediate argillic alteration. Montmorillonite is a type of clay mineral that easily swells at wet condition and easily shrinkages at dry condition. Swelling of clay mineral destroys intersheet and interlayer bonds, and reduces shear strength. The presence of clay minerals in the altered andesitic tuff of intermediate argillic zone can be considered as one of the factors that induced to the Pelangan debris slides. Further studies on geotechnical and slope stability analysis of the landslide area are crucial to be done for better understanding of the characteristics of the altered rocks inducing hazardous landslides.


Clay Minerals ◽  
1966 ◽  
Vol 6 (4) ◽  
pp. 371-382 ◽  
Author(s):  
P. J. Beaven ◽  
M. J. Dumbleton

AbstractClay mineral analyses of Caribbean soils illustrate the differences in composition that can arise from differences in topography and parent material, and emphasize the differences between the groups of proposed new engineering classifications of the soils based on these factors. Within one set of environmental conditions the clay mineral assemblage was reasonably constant. Examples are given of local differences in clay type which were correlated with variations in climate and mode of formation.


Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 618
Author(s):  
Layla Shafei ◽  
Puja Adhikari ◽  
Wai-Yim Ching

Clay mineral materials have attracted attention due to their many properties and applications. The applications of clay minerals are closely linked to their structure and composition. In this paper, we studied the electronic structure properties of kaolinite, muscovite, and montmorillonite crystals, which are classified as clay minerals, by using DFT-based ab initio packages VASP and the OLCAO. The aim of this work is to have a deep understanding of clay mineral materials, including electronic structure, bond strength, mechanical properties, and optical properties. It is worth mentioning that understanding these properties may help continually result in new and innovative clay products in several applications, such as in pharmaceutical applications using kaolinite for their potential in cancer treatment, muscovite used as insulators in electrical appliances, and engineering applications that use montmorillonite as a sealant. In addition, our results show that the role played by hydrogen bonds in O-H bonds has an impact on the hydration in these crystals. Based on calculated total bond order density, it is concluded that kaolinite is slightly more cohesive than montmorillonite, which is consistent with the calculated mechanical properties.


Clay Minerals ◽  
2000 ◽  
Vol 35 (1) ◽  
pp. 25-55 ◽  
Author(s):  
C. V. Jeans ◽  
D. S. Wray ◽  
R. J. Merriman ◽  
M. J. Fisher

AbstractThe nature and origin of authigenic clay minerals and silicate cements in the Jurassic and Cretaceous sediments of England and the North Sea are discussed in relation to penecontemporaneous volcanism in and around the North Sea Basin. Evidence, including new REE data, suggests that the authigenic clay minerals represent the argillization of volcanic ash under varying diagenetic conditions, and that volcanic ash is a likely source for at least the early silicate cements in many sandstones. The nature and origin of smectite-rich, glauconite-rich, berthierine-rich and kaolin-rich volcanogenic clay mineral deposits are discussed. Two patterns of volcanogenic clay minerals facies are described. Pattern A is related to ash argillization in the non-marine and marine environments. Pattern B is developed by the argillization of ash concentrated in the sand and silt facies belts in the seas bordering ash-covered islands and massifs. It is associated with regression/ transgression cycles which may be related to thermal doming and associated volcanism, including the submarine release of hydrothermal fluids rich in Fe. The apparent paucity of volcanogenic clay deposits in the Jurasssic and Early Cretaceous sediments of the North Sea is discussed.


1997 ◽  
Vol 77 (2) ◽  
pp. 295-307 ◽  
Author(s):  
T. A. Okusami ◽  
R. H. Rust ◽  
A. O. Alao

Representative profiles of the Owena, Egbeda, Alagba, and Balogun series were studied. The Owena soil is formed in amphibolite whereas Egbeda and Balogun soils are formed in biotite gneiss derived parent materials. The Alagba soil is formed in sandstone parent rock. The main objectives were to characterize the soils and their clay fraction, and to classify and interpret soil properties for agricultural land use. Most soils exhibit 2.5 YR hues in subsurface horizons. A pedon formed in biotite gneiss has the highest dithionite Fe content and Fed/clay ratio. The relationships between clay content and Fed values vary according to parent material origin and, therefore, would have to be interpreted differently for soil weathering processes. Clay coatings were noticeable in some soil horizons of all pedons studied. Soils are generally medium to slightly acid with sandstone-derived soils being the most acid. The clay mineral suite in all soils is dominated by kaolinite with traces of 2:1 and 2:2 clay minerals, goethite, hematite, anatase, maghemite, and rutile. In addition, some soils contain trace amounts of gibbsite. Kandic horizons have been identified in all soils. The low charge properties of the soils reflect the intensely weathered clay mineral suite. The base status is probably influenced by the cropping system and therefore may tend to unnecessarily differentiate highly weathered soils at the order level. The Egbeda and Balogun series were classified as Rhodic Kandiudults, clayey-skeletal, oxidic and Rhodic Kandiudalfs, clayey-skeletal, oxidic, respectively. Others, Owena, and Alagba series, were classified as Typic Kanhaplohumults, clayey, oxidic and Rhodic Kanhaplustults, fine loamy or clayey, oxidic, respectively. In the FAO-Unesco legend, all soils become Rhodic Ferralsols. In addition, the Owena (with its nitic properties) is further classified as niti-rhodic Ferralsol. The two classification systems are at variance for highly weathered (variable charge property) soils and this difference will definitely influence management decisions depending on which system is used at any particular time. Soil attributes favorable for agricultural use include thick sola and favorable structures. Chemical properties suggest minimal fixation of phosphorus. Key words: Dithionite Fe, kandic, oxidic, variable charge, ferralic, exchangeable Al


2018 ◽  
Vol 788 ◽  
pp. 83-88
Author(s):  
Oskars Leščinskis ◽  
Ruta Švinka ◽  
Visvaldis Švinka

Clays are materials consisting of clay minerals and non-clay minerals. Clay mineral fraction is considered to be a nanofraction. Clay minerals can be used for water purification and treatment. Description and characterization of 3 different Latvian clay nanosized minerals from 3 different geological periods (clay Liepa from Devonian period, clay Vadakste from Triassic period and clay Apriki from Quaternary period) as well as their adsorption capacity concerning organic compounds such as methyl orange and rhodamine B are summarized. Nanosized clay mineral particles were obtained using sedimentation method. Particle size distribution, zeta potential and FTIR spectra is given. The adsorption tests of above mentioned organic compounds were carried out in water solutions at 3 different pH values. The adsorption values were determined by means of UV-spectrophotometric technique. Zeta potential values for clay minerals Apriki, Liepa and Vadakste are -40.9 mV, -49.6 mV and -43.0 mV, respectively. FTIR spectra show similar tendencies for all 3 clay minerals. The best adsorption capacity concerning methyl orange and rhodamine B were in solutions with a pH value of 2, whereas at neutral and alkaline pH values adsorption in 24 hours was not observed.


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