Quantification Curves for XRD Analysis of Mixed-Layer 14Å/10Å Clay Minerals

1995 ◽  
Vol 43 (2) ◽  
pp. 246-254 ◽  
Author(s):  
C. H. Pons
Keyword(s):  
Clay Minerals ◽  
Mixed Layer ◽  
Xrd Analysis

Quantitative XRD bulk and clay mineralogical determination of paleosol sections of Unayzah and Basal Khuff clastics in Saudi Arabia

2012 ◽  
Vol 27 (2) ◽  
pp. 126-130 ◽  
Author(s):  
Shouwen Shen ◽  
Syed R. Zaidi ◽  
Bader A. Mutairi ◽  
Ahmed A. Shehry ◽  
Husin Sitepu ◽  
...  
Keyword(s):  
Clay Minerals ◽  
Clay Mineral ◽  
Mixed Layer ◽  
Size Fraction ◽  
Xrd Analysis ◽  
Ratio Method ◽  
Type I ◽  
Rock Formations ◽  
Refinement Method

Quantitative X-ray diffraction (XRD) analysis is performed on 172 samples mainly containing paleosol sections of Unayzah and Basal Khuff clastics taken from the core of one well drilled by Saudi Aramco. Quantitative XRD bulk mineralogical determination is achieved using the Rietveld refinement method whereas quantitative XRD clay mineralogical determination of clay-size fraction is obtained using the reference intensity ratio method. The XRD results indicate that the samples from paleosol sections consist mainly of quartz and feldspar (microcline and albite) as framework constituents. Cement minerals include dolomite, hematite, anhydrite, siderite, gypsum, calcite, and pyrite. Clay minerals are important constituents in paleosols. The XRD results show that clay minerals in the samples are illite, mixed-layer illite/smectite, kaolinite, and chlorite. No discrete smectite is present in the samples. The clay mineral associations in these samples of paleosol sections can be classified into three types: Type I predominantly consists of illite and a mixed layer of illite/smectite; Type II of kaolinite; and Type III of illite and a mixed layer of illite/smectite, but also significant amounts of kaolinite. The change of clay mineral association type with sample depth can indicate the change of paleoclimate and paleoenvironment. For example, kaolinite usually forms under strongly leaching conditions such as abundant rainfall, good drainage, and acid waters. Therefore, XRD mineralogical data of paleosol sections are important for petroleum geologists to study paleoclimate and paleoenvironment and to predict the reservoir quality of the associated rock formations.

scholarly journals Clay Mineralogy and Geochemistry of the Pockmarked Surface Sediments from the Southwestern Xisha Uplift, South China Sea: Implications for Weathering and Provenance

Geosciences ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
Mei Zhang ◽  
Hongfeng Lu ◽  
Qing Chen ◽  
Gayan Bandara ◽  
Hui Zhang ◽  
...  
Keyword(s):  
South China Sea ◽  
Clay Minerals ◽  
South China ◽  
Surface Sediments ◽  
Northern South China Sea ◽  
Clay Mineralogy ◽  
Xrd Analysis ◽  
Average Weight ◽  
X Ray ◽  
China Sea

In the northern South China Sea, pockmarks are widely distributed on the seabed offshore on the southwestern Xisha Uplift. The mineralogy and geochemistry of the clay minerals and surface sediments from the pockmark field were identified using X-ray diffraction (XRD) analysis and X-ray fluorescence (XRF) analysis to trace the provenance, weathering, and sediment transportation system in the area. The clay minerals are primarily comprised of illite, smectite, kaolinite, and chlorite, showing a distribution of average weight percentages of 35%, 35%, 18%, and 13%, respectively. Based on the surrounding fluvial drainage basins and various transport mechanisms (current or monsoon), illite and chlorite primarily originate from rivers in Taiwan and the Mekong and Red Rivers. Kaolinite primarily originates from the Pearl River, and smectite derived from the Luzon arc system is primarily transported by surface currents with significant influence from the Kuroshio intrusion.

An occurrence of polymorphic halloysite in granite saprolite of the Bayerischer Wald, Germany

Clay Minerals ◽  
1978 ◽  
Vol 13 (1) ◽  
pp. 67-77 ◽  
Author(s):  
B.-M. Wilke ◽  
U. Schwertmann ◽  
E. Murad
Keyword(s):  
Trace Elements ◽  
Clay Minerals ◽  
Iron Oxides ◽  
Aqueous Phase ◽  
Mixed Layer ◽  
Thin Plates ◽  
Low Crystallinity

AbstractXRD, DTA and IR patterns showed clay veins filling fissures in a granite of the Bayerischer Wald (eastern Bavaria) to consist mainly of hydrated halloysite of low crystallinity with traces of gibbsite, 2:1 (mixed layer) clay minerals and iron oxides. The halloysite forms thin plates which exhibit varying degrees and types of enrolment, resulting in platy, tubular and spheroidal crystals within the same sample. Concentrations of the trace elements Rb, Sr, Ba, Zr, Y, Ce, Pb, Zn and Cu indicate halloysite formation to have taken place via an aqueous phase under the influence of vadose waters circulating in fissures.

scholarly journals Controls on Associations of Clay Minerals in Phanerozoic Evaporite Formations: An Overview

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 974
Author(s):  
Yaroslava Yaremchuk ◽  
Sofiya Hryniv ◽  
Tadeusz Peryt ◽  
Serhiy Vovnyuk ◽  
Fanwei Meng
Keyword(s):  
Clay Minerals ◽  
Mixed Layer ◽  
Potassium Salt ◽  
Salt Precipitation ◽  
Mineral Association ◽  
Pyroclastic Material ◽  
Upper Proterozoic ◽  
Chemical Type ◽  
Cyclic Changes ◽  
Brine Concentration

Information on the associations of clay minerals in Upper Proterozoic and Phanerozoic marine evaporite formations suggests that cyclic changes in the (SO4-rich and Ca-rich) chemical type of seawater during the Phanerozoic could affect the composition of associations of authigenic clay minerals in marine evaporite deposits. The vast majority of evaporite clay minerals are authigenic. The most common are illite, chlorite, smectite and disordered mixed-layer illite-smectite and chlorite-smectite; all the clay minerals are included regardless of their quantity. Corrensite, sepiolite, palygorskite and talc are very unevenly distributed in the Phanerozoic. Other clay minerals (perhaps with the exception of kaolinite) are very rare. Evaporites precipitated during periods of SO4-rich seawater type are characterized by both a greater number and a greater variety of clay minerals—smectite and mixed-layer minerals, as well as Mg-corrensite, palygorskite, sepiolite, and talc, are more common in associations. The composition of clay mineral association in marine evaporites clearly depends on the chemical type of seawater and upon the brine concentration in the evaporite basin. Along with increasing salinity, aggradational transformations of clay minerals lead to the ordering of their structure and, ideally, to a decrease in the number of minerals. In fact, evaporite deposits of higher stages of brine concentration often still contain unstable clay minerals. This is due to the intense simultaneous volcanic activity that brought a significant amount of pyroclastic material into the evaporite basin; intermediate products of its transformation (in the form of swelling minerals) often remained in the deposits of the potassium salt precipitation stage.

Jurassic clay mineral assemblages and their post-depositional alteration: upper Great Estuarine Group, Scotland

1987 ◽  
Vol 124 (3) ◽  
pp. 261-271 ◽  
Author(s):  
Julian E. Andrews
Keyword(s):  
Clay Minerals ◽  
Clay Mineral ◽  
Mixed Layer ◽  
Middle Jurassic ◽  
Water Circulation ◽  
Hot Water ◽  
Geothermal Gradients ◽  
Fine Grained ◽  
Igneous Intrusions ◽  
Mineral Assemblages

AbstractClay minerals from Middle Jurassic lagoonal mudrocks, siltstones and silty fine-grained sandstones of the upper Great Estuarine Group (Bathonian) are divided into four assemblages. Assemblage 1, the most common assemblage, is rich in mixed-layer illite–smectite with attendant illite and kaolinite. Assemblage 2 is dominated by smectitic clay. These assemblages are indicative of primary Jurassic deposition. Illite and kaolinite were probably derived from the weathering of older rocks and soils in the basin hinterland and were deposited in the lagoons as river-borne detritus. The majority of smectite and mixed-layer illite–smectite is interpreted as the argillization product of Jurassic volcanic dust, also deposited in the lagoons by rivers. Near major Tertiary igneous intrusions these depositional clay mineral assemblages have been altered. Assemblage 3 contains smectite-poor mixed-layer illite–smectite, whilst Assemblage 4 contains no smectitic clay at all. Destruction of smectite interlayers occurred at relatively shallow burial depths (< 2500 m) due to enhanced geothermal gradients and local convective hot-water circulation cells associated with the major Tertiary igneous intrusions.

Nanomaterials From Mixed-Layer Clay Minerals: Structure, Properties, and Functional Applications

2019 ◽  
pp. 365-413
Author(s):  
Hongbing Deng ◽  
Yang Wu ◽  
Iqra Shahzadi ◽  
Rong Liu ◽  
Yang Yi ◽  
...  
Keyword(s):  
Clay Minerals ◽  
Mixed Layer ◽  
Functional Applications ◽  
Structure Properties

Identification of Mixed-Layer Mineral of Cambodian Clays and their Phase Changes upon Firing

2012 ◽  
Vol 620 ◽  
pp. 72-76
Author(s):  
Bun Kim Ngun ◽  
Mohamad Hasmaliza ◽  
Kiyoshi Okada ◽  
Phat Bone ◽  
Zainal Arifin Ahmad
Keyword(s):  
Mixed Layer ◽  
Mineralogical Composition ◽  
Xrd Analysis ◽  
Phase Changes ◽  
Rational Analysis ◽  
Qualitative And Quantitative ◽  
Mineral Phases ◽  
Clay Deposits ◽  
Layer Mineral

Representative of clay deposits from central Cambodia were analyzed in terms of their mineral phases, mineralogical composition and phase changes after firing by qualitative and quantitative XRD analysis. To examine the phase changes, the samples were prepared and fired from 950 to 1200 °C. Results show that Cambodian clays contained quartz, illite, kaolinite, and chlorite-vermiculite mixed-layer as dominant mineral phases and the minor phases of albite and calcite also appeared in the samples. The rational analysis shows that chlorite-vermiculite was the main mineral in all Cambodian clays. After the samples were preceded upon firing, new phases of mullite, hematite and crystobalite were appeared above 1050 °C.

Clay Minerals Associated with the Precambrian Gowganda Formation of Ontario

Clay Minerals ◽  
1970 ◽  
Vol 8 (4) ◽  
pp. 471-477 ◽  
Author(s):  
R. W. Tank ◽  
L. McNeely
Keyword(s):  
Clay Minerals ◽  
Mixed Layer ◽  
Low Grade ◽  
High Grade ◽  
X Ray ◽  
Grade Metamorphism ◽  
Layer Material

AbstractX-ray analyses indicate that chlorite, illite and mixed-layer chloritesmectite are present in the < 2μ fraction of the Precambrian Gowganda Formation near Bruce Mines, Ontario. The mixed-layer material is restricted to the porous graywacke sandstones and is epigenetic in origin. The chlorite and illite are ubiquitous and may reflect high-grade diagenesis, low-grade metamorphism or a source rich in these minerals.

scholarly journals Clay minerals in sediments from contact zones with basalt sills

2019 ◽  
pp. 234-247
Author(s):  
V. B. Kurnosov ◽  
B. A. Sakharov ◽  
A. R. Geptner ◽  
Yu. I. Konovalov ◽  
E. O. Goncharov
Keyword(s):  
Phase Composition ◽  
Clay Minerals ◽  
Mixed Layer ◽  
Gulf Of California ◽  
Layered Silicates ◽  
Total Thickness ◽  
Upper Pleistocene ◽  
X Ray ◽  
Diffraction Patterns ◽  
Trioctahedral Smectite

Clay minerals (fraction <0.001 mm) of Upper Pleistocene clayey-sandy-silty sediments recovered by DSDP Holes 481 and 481A in the Northern Trough, Guaymas Basin, Gulf of California, were studied by X-ray based on the modeling of diffraction patterns and their comparison with experimental diffractograms. Terrigenous clay minerals are represented mainly by dioctahedral micaceous varieties (mixed-layer disordered illite-smectites, illite) with the chlorite admixture and by kaolinite in the upper section of unaltered sediments. Intrusion of hot basalt sills (total thickness of the complex is about 27 m) provoked alterations in the phase composition of clay minerals in sediments (7.5 m thick) overlying the sill complex. These sediments include newly formed triooctahedral layered silicates (mixed-layer chlorite-smectites, smectite). Sediments inside the sill complex include trioctahedral mixed-layer mica-smtctite-vermiculite or trioctahedral smectite. The trioctahedral mixed-layer chlorite-smectite coexisting with smectite was found in a single sample of the same complex.

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