Clay mineral and grain size studies of sediment provenances and paleoenvironment evolution in the middle Okinawa Trough since 17ka

2015 ◽  
Vol 366 ◽  
pp. 49-61 ◽  
Author(s):  
Jiaze Wang ◽  
Anchun Li ◽  
Kehui Xu ◽  
Xufeng Zheng ◽  
Jie Huang
Keyword(s):  
Grain Size ◽  
Clay Mineral ◽  
Okinawa Trough ◽  
Paleoenvironment Evolution

A Study of Adobes Made with No Usual Soils Concerning Grain Size Distribution Test

2017 ◽  
Vol 864 ◽  
pp. 346-350
Author(s):  
M.A.P. Rezende ◽  
R.C. Alves ◽  
E.V.M. Carrasco ◽  
J.N.R. Mantilla ◽  
M.A. Smits ◽  
...  
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Clay Mineral ◽  
Building Material ◽  
Atterberg Limits ◽  
Soil Behavior ◽  
Mineral Structure

This article presents and discusses an adobe production with shows a clay/silt/sand proportion that is completely different from that recommended by most authors and construction associations. The main objective was to improve comprehension of earth behaviors as building material by studying these two atypical cases of adobe production. The soil was analyzed by different tests as the grain size distribution test and Atterberg limits. Adobe resistance was tested using a methodology proposed by Proterra network which was created by a group of researchers from different Iberian American laboratories. This methodology was used in Ph.D. thesis, too. The results show a soil with 1% clay and 65.1 silte and an average of resistance of 2.11 MPa for the adobes. These results show the importance of the clay mineral structure and the complexity of the soil behavior, indicating the need for additional studies.

A mineralogical and geochemical study of turbidite sandstones and interbedded shales, Mam Tor, Derbyshire, UK

Clay Minerals ◽  
1981 ◽  
Vol 16 (4) ◽  
pp. 333-345 ◽  
Author(s):  
D.A. Spears ◽  
M.A. Amin
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Clay Mineral ◽  
Mixed Layer ◽  
Clay Mineralogy ◽  
Lateral Variation ◽  
Size Fractions ◽  
Shore Line ◽  
Geochemical Study ◽  
Size Sorting

AbstractEleven shales and fourteen turbidite sandstones from the Mam Tor Beds were analysed chemically and by XRD. The ratio of kaolinite to illite plus mixed-layer clay was higher in the sandstones than in the shales, size fractions demonstrating that this ratio decreased as the grain size decreased. Shales more basinal in character than those of the Mam Tor Beds contain more illite and mixed-layer clay and less kaolinite and it is suggested that there was a lateral variation in clay mineralogy with distance from the shore line due to particle size sorting and that the character of the clay mineral fraction was retained as the turbidity current transported sediment from a nearshore environment deeper into the basin. Support for this model was obtained from the geochemistry which showed that the sandstone matrix differed compositionally from the shales. Systematic variations occurred in the turbidite sandstones but not in the shales which are therefore considered to be non-turbiditic. Only minor mineralogical changes appear to have occurred during diagenesis.

Provenance discrimination of the clay sediment in the western Taiwan Strait and its implication for coastal current variability during the late-Holocene

The Holocene ◽  
2016 ◽  
Vol 27 (1) ◽  
pp. 110-121 ◽  
Author(s):  
Jing Chen ◽  
Junqiang Ma ◽  
Kehui Xu ◽  
Yan Liu ◽  
Wenhong Cao ◽  
...  
Keyword(s):  
Grain Size ◽  
Clay Mineral ◽  
Late Holocene ◽  
Sediment Accumulation ◽  
Taiwan Strait ◽  
Surficial Sediment ◽  
Tidal Mixing ◽  
Coastal Current ◽  
Inner Shelf ◽  
Sediment Samples

This study aims to quantify the contribution of Yangtze clays to the sediment accumulation in the western Taiwan Strait and reconstruct the strength of Chinese Coastal Current (CCC) since middle-Holocene driven by East Asian Winter Monsoon (EAWM). Both down-core and surficial sediment samples were collected for grain size, radiocarbon, and clay mineral analyses. One 250-cm-long core was collected from the southern Yangtze distal mud wedge in western Taiwan Strait which receives Yangtze-derived clays transported by the Zhejiang-Fujian Coastal Current (ZFCC), the southern part of CCC. Clay minerals were examined in surficial sediment samples which were influenced by the Yangtze, Zhejiang-Fujian, western Taiwanese rivers, and the inner-shelf mud wedge. Ternary diagrams of smectite–kaolinite–chlorite revealed that three endmembers represented the Yangtze, Min, and western Taiwanese rivers, respectively. The estuaries seaward of the tidal current limits of Zhejiang-Fujian rivers, especially the Qiantang and Ou, were influenced by Yangtze-derived sediments through energetic tidal mixing. It was found that smectite can be used as a fingerprint of the Yangtze fine-grained sediment because among all the studied rivers, the Yangtze is the only one supplying smectite. Clay mineral results in core sediments revealed a dramatic provenance change at the depth of 113 cm, dated at ~4.0 cal. kyr BP. Smectite disappeared in the upper core, suggesting decreased contribution of Yangtze clays to the southern distal mud wedge. Decreased grain size of the fine population in the upper core also indicated that the ZFCC weakened during the late-Holocene. Such a decline also occurred in Subei Coast Current (northern part of CCC), revealed by the previous studies. The decline of CCC was related to the decreased EAWM of the late-Holocene, and it resulted in decreased sediment accumulation rate of the inner-shelf mud.

Complex permittivity and clay mineralogy of grain-size fractions in a wet silt soil

Geophysics ◽  
2008 ◽  
Vol 73 (3) ◽  
pp. J1-J13 ◽  
Author(s):  
Steven Arcone ◽  
Steven Grant ◽  
Ginger Boitnott ◽  
Benjamin Bostick
Keyword(s):  
Grain Size ◽  
Clay Minerals ◽  
Clay Mineral ◽  
Complex Permittivity ◽  
Mineral Content ◽  
Size Fraction ◽  
Clay Mineralogy ◽  
Free Water ◽  
Size Fractions ◽  
Grain Size Fractions

We determined the complex permittivity and clay mineralogy of grain-size fractions in a wet silt soil. We used one clay-size fraction and three silt-size fractions, measured permittivity with low error from [Formula: see text] with time-domain spectroscopy, and estimated mineral weight percentages using X-ray diffraction (XRD). The volumetric water contents were near 30%, and the temperature was [Formula: see text]. For the whole soil, standard fractionation procedures yielded 2.4% clay-size particles by weight, but XRD showed that the phyllosilicate clay minerals kaolinite, illite, and smectite made up 17% and were significantly present in all fractions. Above approximately [Formula: see text], all real parts were similar. Below approximately [Formula: see text], the real and imaginary permittivities increased with decreasing grain size as frequency decreased, and the imaginary parts became dominated by direct-current conduction. Similarly, below approximately [Formula: see text], the measured permittivity of montmorillonite, a common smectite, dominated that of the other clay minerals. Total clay mineral and smectite mass fractions consistently increased with decreasing grain size. Below [Formula: see text], a model with progressively increasing amounts of water and parameters characteristic of montmorillonite matches the data well for all fractions, predicts permittivities characteristic of free water in smectite structural galleries, and shows that the similar real parts above [Formula: see text] are caused by a small suppression of the high-frequency static value of water permittivity by the smectite. We conclude that the clay mineral content, particularly smectite, appears to be responsible for permittivity variations between grain-size fractions. Small model mismatches in real permittivity near the low-frequency end and the greater fractions of kaolinite and illite suggest that the total clay mineral content might have been important for the coarser fractions.

scholarly journals Growth Mechanism of Siliceous Cement in Tight Sandstone and Its Influence on Reservoir Physical Properties

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3133 ◽  
Author(s):  
Bo Jiu ◽  
Wenhui Huang ◽  
Jing Shi ◽  
Mingqian He
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Clay Mineral ◽  
Growth Mechanism ◽  
Forming Process ◽  
Tight Sandstone ◽  
High Quality ◽  
Factors Affecting ◽  
Reservoir Permeability ◽  
Thin Section Analysis

To investigate the effect of siliceous cementation on the densification of sandstone and the forming process of tight sandstone, based on cathodoluminescence, scanning electron microscopy and thin section analysis, the growth mechanism and characteristics of quartz particles in tight sandstone formations are explored. Meanwhile, combined with conventional core analysis and X-ray diffraction experiments, the factors affecting the crystallization of quartz particles, including the chlorite content, grain size and clay mineral, are analyzed, respectively. The entire siliceous cementation is divided into two processes. The first part is the process in which the weathered and rounded particles in the formation are restored to the hexagonal dipyramid crystal by siliceous cementation. The second part is the process of coaxial growth that the hexagonal dipyramid crystal continues to increase with the form of micro-quartz film. As siliceous cements continue to increase, the petrological characteristics of sandstones are constantly changing. The tight sandstone developed in the study area is composed of lithic sandstone and quartz lithic sandstone. Based on the analysis results, 2D and 3D evolution models are established for densification of two different lithic sandstones. When the content of siliceous cement in the study area is less than 17%, the porosity of tight sandstone increases with the increase of cement. When the content of cement is more than 17%, the porosity of tight sandstone is negatively correlated with the content of cement. When the cement content is greater than 10%, the reservoir permeability is negatively correlated with it. Furthermore, the particle size mainly affects the permeability of reservoir, and the particle size is negatively correlated with the permeability of tight sandstone. The most high-quality tight sandstone reservoir in the study area is in the first cementation stage when siliceous cements are distributed in porphyritic texture with the content of 10–15% and a grain size of 0.2–0.3 mm. In addition, the relatively high-quality reservoir is the one developing clay mineral film with a content of cementation about 5–12%.

scholarly journals Grain Size Distribution and Clay Mineral Distinction of Rare Earth Ore through Different Methods

Minerals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 353 ◽  
Author(s):  
Lingkang Chen ◽  
Xiongwei Jin ◽  
Haixia Chen ◽  
Zhengwei He ◽  
Lanrong Qiu ◽  
...  
Keyword(s):  
Grain Size ◽  
Rare Earth ◽  
Clay Minerals ◽  
Clay Mineral ◽  
Solution Concentration ◽  
Low Ph ◽  
Low Grade ◽  
Leaching Rate ◽  
Leaching Solution

Although clay mineral content in ion-absorbed rare earth ores is crucial for migrating and releasing rare earth elements, the formation, distribution, and migration of clay minerals in supergene rare earth ores have not been fully understood. Therefore, this study analyzes the characteristics of clay mineral type and content, soil particle size, pH value, leaching solution concentration, and leaching rate. This analysis was performed using different methods, such as regional rare earth mine soil surveys, in situ leaching profile monitoring, and indoor simulated leaching. The results showed that the grain size and volume curve of rare earth ore have unimodal and bimodal shapes, respectively. X-ray diffraction showed the differences in clay mineral types formed by different weathered bedrocks. The principal clay minerals were kaolinite, illite, chlorite, and vermiculite, with their relative abundance varying with parent rock lithology (granite and low-grade metamorphic rocks). In the Ganxian granite weathering profile, the kaolinite content increased from top to bottom. The decomposition of feldspar minerals to kaolinite was enhanced with an increase in the SiO2 content during weathering. The in situ leaching profile analysis showed that the kaolinite content increased initially and then decreased, whereas the illite/mica content exhibited the opposite trend. Under stable leaching solution concentration and leaching rate, clay mineral formation is favored by lower pH. Low pH, low leaching rate, and highly-concentrated leaching solution (12 wt%) resulted in a slow increase in kaolinite content in the upper part of the profile (30 cm). A lower concentration of the leaching solution (4 wt%) resulted in rapid enrichment of kaolinite after 15 days. Low pH, leaching solution concentration, and leaching rate promoted the formation of distinct kaolinite horizons. We suggest that by disregarding other control factors, rare earth recovery of over 90% can be achieved through leach mining with solutions of 8 wt% and a pH of 5 at a leaching rate of 5 mL/min.

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