• Economic and Environmental Geology
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• v.50 no.1
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• pp.15-26
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• 2017

Advanced argillic, argillic, and phyllic zones are the most important alteration patterns to predict the hidden ore body during exploration of hydrothermal deposits. We examined the quantitative relationship between the spectral absorption characteristics and the mineral content of the synthetic mixtures such as alunite-kaolinite and illite-kaolinite using short wavelength infrared (SWIR) spectroscopy. In the alunite-kaolinite mixtures, the spectral absorption characteristics of the alunite was highly correlated with the Hull quotient reflectance(0.99) and the kaolinite had the highest correlation with the Gaussian peak(0.92). Illite-kaolinite mixtures are essential for Gaussian deconvolution because of the overlap of absorption region. Illite and kaolinite mixtures indicate the high correlation of 0.93 and 0.98, respectively. The error ranges in the alunite-kaolinite(8%) and illite-kaolinite mixtures(5%) derived from SWIR were smaller than the ones(29% and 26%) obtained from X-ray diffraction(Rietveld) analysis. These results show that SWIR spectroscopic analysis is more reliable than XRD Rietveld analysis in terms of quantification of allowed minerals.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.837-843
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• 2010

This research investigated classification of clay activity degree by different clay mineral components. Based on compositions of different clay and oxide minerals within 390 soil series in Korea, 7 soils were selected to analyze for CEC and specific surface area of clay minerals. As a result, soils were mainly composed with Chlorite originated from sandstone, Smectite originated from Andesite porphyry and combination of Allophane and Ferrihydrite originated from volcanic ash, if the ratio of CEC value to clay content (degree of clay activity) was greater than 0.7. If the degree of clay activity was ranged between 0.3 and 0.7, soils were composed mainly with Kaolin originated from anorthite. Soils with this ratio also was composted with combinations of Kaolin, Illite and Vermiculite originated with river deposits. When the degree of the activity was less than 0.3, soils were commonly red-yellowish color and composed with two different minerals. One type of composition was Kaolin originated from granite and granite gneiss and the soils contained Geothite and Hematite. The other type was composited mainly with Illite and Vermiculite minerals originated from granite. These soils contained Gibbsite, Geothite and Hematite. The degree of clay activity was highly related with CEC and specific surface area. The greater degree of the activity displayed greater values of clay CEC and specific surface area. It is not easy to measure actual quantity and compositions of clay minerals, while the degree of clay activity can be measured from routine soil analyses. As a conclusion, the degree of clay activity may be not just a simple but also powerful tool to estimate physical-chemical properties of soils and to evaluate the soil classification in Korean soils.

• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.195-195
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• 2005

• Proceedings of the Petrological Society of Korea Conference
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• 2009.05a
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• pp.91-94
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• 2009

• 한국전자현미경학회:학술대회논문집
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• 1993.06a
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• pp.24-24
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• 1993

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.392-393
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• 2018

• Geotechnical Engineering
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• v.14 no.6
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• pp.73-80
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• 1998

In order to identify clay minerals in the soft ground, which has been deposited along the coastline of the Korean peninsula, 14 samples have been taken at different locations and then X-ray diffraction analysis is carried out for them. It is known from the analysis that the various kinds of clay minerals mixed with different portions exist in the soft ground, but halloysite is not traced in any samples. It is featured regionally that kaolinite and illite are found in the western coast and the southern coast. Montmorillonites exists only in the western coast. This feature of regional occurrences can be explained with the help of geology of the region. Activities determined from physical properties of the soils do not coincide with those of clay minerals identified from X-ray diffraction analysis.

• Journal of the Korean earth science society
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• v.25 no.1
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• pp.1-9
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• 2004

The clay minerals of thirty-four bottom sediments collected from the northwestern continental shelf of the East China Sea have been determined by X-ray diffraction analysis. The clay mineral distribution is mainly controlled by the sediment source and the dominant circulation pattern. The predominant clay mineral in our study area is illite comprising more-than 70% of whole clay fraction. The highest concentration of illite (>72%) is found in the southeastern offshore parts beyond the reach of terrigenous input from the Cheju Island. It means that these illites are largely transported by the Kuroshio Current from the South China Sea. Smectite is highly concentrated in the northwest middle part and in the outer-shelf mud patch. It seems to be due to the high supply of smectite transported from China where the fine-grained sediments are discharged from the modern and ancient Huanghe River. The relatively high abundance of kaolinite is likely derived from the Changjiang River via Taiwan ·Warm Current. In contrast, the large amounts of chlorite and high chlorite/kaolinite ratios occur in the northwestern are, reflecting the transportation by the Huanghai Sea Coastal Current from the southern Yellow Sea.

• The Journal of Engineering Research
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• v.5 no.1
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• pp.57-62
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• 2004

Korean natural zeolite with feldspar and illite as impurities was purified by an air classification method. X-ray powder diffraction analyses showed that the air classification effectively separated zeolite and impurities, and reduce the amount of impurity of the natural zeolite. The zeolite with air classification was treated with 1N NaOH solutions at temperatures at 100, 150, $200^{\circ}C$ for 17hours. The obtained hydrothermal treatment of phase change to phillilsite and analcime from mordenite and clinoptilolite.

• Journal of the Mineralogical Society of Korea
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• v.19 no.1 s.47
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• pp.39-48
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• 2006

X-ray diffaction and chemical analysis were used for mineralogical characteristics of weathering grade of granite and biotite gneiss. Granite is composed mainly of quartz, albite, and minor K-feldspar and biotite gneiss is biotite, quartz, albite. Illite and kaolinite increased in granite, and vermiculite and halloysite in biotite gneiss as increasing weathering process. The percentages of $Al{2}O_{3}$ increase but that of CaO, $Na_{2}O,\;K_{2}O$ decrease as the weathering process. $Fe_{2}O_{3}$ different from granite and biotite gneiss.