• Economic and Environmental Geology
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• v.50 no.6
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• pp.497-508
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• 2017

This study was carried out to document and diagnose the conditions of the seated stone statue of Buddhist Master Seungga in Seunggasa temple immediately after its conservation treatment, which was found to be long covered in surface of white materials. The stone Halo was researched along with the Statue, and basic data was secured through precisely examination and nondestructive diagnosis. The result from the surface deterioration evaluation shows that both the Statue and Halo had a little bit of physical deterioration, although their level of chemical deterioration was proportionally higher due to discoloration. The physical property diagnosis using ultrasonic measurements on the Statue and Halo showed that the average ultrasonic velocity was found to be 3,570 m/s and 3,373 m/s, respectively, which corresponds to grade III, an indication of a favorable physical property. The surface covered materials were detected to be Ca, Ti, Pb, Fe, Al and Si, emanating from Hobun (Oster shell powder; $CaCO_3$) or lime ($CaO{\cdot}Ca(OH)_2$) and silicate minerals. Furthermore, Ti and Pb seems to be the component of the white coloring pigments, titanium white ($TiO_2$) and white lead ($2PbCO_2{\cdot}Pb(OH)_2$). Therefore, the seated stone statue of Buddhist Master Seungga is presumed to be painted with Hobun or lime and thereafter painted over with titanium white and white lead.

• Journal of the Mineralogical Society of Korea
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• v.28 no.4
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• pp.325-332
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• 2015

Apophyllite (KF)($K_{0.84}Ca_{3.99}Si_{7.70}O_{20}F_{0.72}{\cdot}8H_2O$), one of the sheet silicates, was compressed up to 7.7 GPa at ambient temperature and 15 high pressure data were obtained. Lattice parameters of the starting specimen were as follows: $a_0=8.954(2)\;{\AA}$, $c_0=15.795(2)\;{\AA}$, $V_0=1266.4(4)\;{\AA}^3$. Symmetrical diamond anvil cell was employed with synchrotron radiation in the mode of angular dispersive X-ray diffraction. Bulk modulus was determined to be 59(4) GPa when ${K_0}^{\prime}$ is 4. No clear first order phase transition symptom was observed in the series of XRD pattern. However, second-order phase transition cannot be ruled out from the correlation between normalized pressure and strain.

• Journal of the Mineralogical Society of Korea
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• v.20 no.4
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• pp.367-376
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• 2007

Aenigmatite, $Na_4(Fe^{2+},Ti,Fe^{3+}){_{12}}(Fe^{3+},Si){_{12}}O_{40}$, is a common constituent of sodium-rich alkaline igneous rocks and is classified a an open-branched single-chain silicate. $M\ddot{o}ssbauer$ spectroscopy of three natural aenigmatite specimens were done and the detailed crystal chemistry was obtained. Fitting of $M\ddot{o}ssbauer$ spectra led to the resolution of nine peaks. They consist of three doublets of $Fe^{2+}/oct$ and one merged peak at low velocity matching to two small peaks at high velocity which were assigned to $Fe^{3+}/tet\;and\;Fe^{2+}/oct$, respectively. Using the peak area for $Fe^{2+}\;and\;Fe^{3+}$ peaks, analytical data were recalculated. Precise assignment of $Fe^{2+}\;and\;Fe^{3+}$ ions in tetrahderal and octahedral sites revealed detailed crystal chemistry of aenigmatite. The existence of significant amounts of $Fe^{3+}/tet$ indicates that $Fe^{3+}$ has preference over $Al^{3+}$ for the tetrahedral sites. Crystal chemistry of aenigmatite (AEN1) yields the formula of $(Na_{3.97}Ca_{0.03})(Ca_{0.11}Mn_{0.59}Fe^{2+}{_{8.07}}Ti_{2.07}Mg_{0.70}Fe^{3+}{_{0.43}}Al_{0.04})(Fe^{3+}{_{0.56}}Al_{0.18}Si_{11.26})O_{40}$.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.109-113
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• 2007

In order to establish the fertilization and soil management method in Gyehwa reclaimed tidal land, we investigated soil property and actual farming condition. Soil properties of 100 field paddy soil and farming surveys of 177 farm households were conducted. Average of effective soil depth was 17.8 cm, which was very smaller than the optimum level 50 cm. The hardness and bulk density of subsoil were $12.40kg\;cm^{-2}$ and $1.59g\;cm^{-3}$, respectively. These results showed that soil physical condition of Gyehwa reclaimed tidal land was very poor. Soil salinity ranged from 0.03 to 0.12%, and average of pH was 6.0, which implied that desalinization of Gyehwa reclaimed tidal land was progressed. However, soil nutrients in Gyehwa reclaimed tidal land were very unbalanced conditions as following, available phosphate $58mg\;kg^{-1}$, available silicate $85mg\;kg^{-1}$, cation exchangeable capacity $7.4cmolc\;kg^{-1}$ and organic matter $8.6g\;kg^{-1}$. On the farm household in Gyehwa reclaimed tidal land, fertilization amounts were $200-54-61(N-P_2O_5-K_2O)kg\;ha^{-1}$ They mainly practiced spring tillage(84%) rather than autumn tillage(16%), and only 14% of them applied rice straw annually in the paddy soil.

• Economic and Environmental Geology
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• v.56 no.4
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• pp.475-499
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• 2023

To infer the provenance of raw iron materials utilized in iron production at the archaeological sites in Gyeongsang province, petrographic and geochemical analyses were conducted for smelting samples and major iron ores sourced from ore deposits. The smelting samples excavated from various iron archaeological sites were classified into different types according to their refining processes, such as iron bloom, iron bloom slag, pig iron, pig iron slag, forging iron flake, smithery iron, iron flake, and arrowhead. These samples exhibited discernable differences in their mineralogical components and texture. The enrichments of major elements such as aluminum and calcium in silicate minerals of the residual slags and the high contents of trace elements such as nickel and copper in some iron-making relics reflect the characteristics of raw iron ores, and thus can be regarded as potential indicators for inferring the provenance of source materials. In particular, the compositional ranges of Pb-Sr isotope ratios for the iron smelting samples were classified into three categories: 1) those exhibiting similar ratios to those of the raw iron ores, 2) those enriched in strontium isotope ratio, and 3) those enriched in both lead and strontium isotope ratios. The observed distinct Pb-Sr isotope characteristics in the iron smelting samples suggest the potential contribution of specific additives being introduced during the high-temperature refining process. These results provide a new perspective on the interpretation of the provenance study of the iron archaeological samples in Gyeongsang province, particularly in terms of the potential contribution of additives on the refining process.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.4
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• pp.259-267
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• 1990

This study was carried out by investigating the changes of physico-chemical and mechanical properties of Gwanghwal and Poseung series in order to obtain basic information on the soil improvement and management. 1. In Gwanghwal series, the content of salt in soil and ground water before rice transplanting at the 21st year after reclamation were 0.29 and 1.02 percent respectively, and the safty cultivation of paddy rice was possible after 33 years of reclamation in both soil series. 2. Clay contents. atterberg limits and clay activity according to the age of reclaimation showed negative correlation. but sand content and N-value were positive in them. 3. Cone index was lower than $3kg/cm^2$ for the first 5 years after reclaimation in both soil series, and the formation of hard pan were 33rd and 49th year after reclamation in Gwanghwal and Poseung series respectively, and its thickness was more in Poseung than in Gwanghwal series. 4. Shearing resistance decreased with the age of reclaimation in both soil series. and friction resistance increased in Gwanghwal than Poseung siries. 4. Shearig resistance decreased with the age of reclaimation in both soil series, and friction resistance increased in Gwanghwal than Poseung series. 5. Soil pH. available, $SiO_2$, $Mg^2$, $K^+$, $Na^+$ and C. E. C showed negative correlation. with the year cultivated paddy rice. but O. M. ava ilable $P_2O_5Ca^{2+}$ and T-N had positive one in both soil series. Contents of O. M and $Ca^{2+}$ and T-N had positive one in both soil series. Contents of O. M and $Ca^{2+}$ were high in Gwanghwal, but C. E. C. was in Poseung series.

• Economic and Environmental Geology
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• v.34 no.4
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• pp.329-343
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• 2001

The deep environment and geochemical evolution of the Bugok geothennal waters, located in the Kyeongnam Province, was re-interpreted based on the hydrochemical and isotopic data published by Yun et al. (1998). The geothermal waters of the Bugok area is geochemically divided into three groups; Geothennal water I, II and III groups. Groups I and II are geochemically similar; high temperature (55.2-77.2$^{\circ}$C) and chemically belonging to Na-S04 types. However, pH and Eh values are a little different each other and Group II water is highly enriched in S04 compared to Group I water. Group III water, occurring from peripheral sites of the central part of the geothennal waters, shows temperature range of 29.3 to 47.0$^{\circ}$C and belongs to $Na-HCO_3-S0_4$ types. The deep environment and geochemical evolution of the Bugok geothennal waters, showing the diversity of geochemistry, can be interpreted as follows; I) Descending to great depth of meteoric waters that originated at high elevation and reacting with sediments and/or granites in depth. The $S0_4$ concentration of the waters has been increased by the dissolution of sulfate minerals in sediments. 2) During the continuous descending, the waters has met with the reduction environment, producing the $H_2S$ gas due to sulfate reduction. The waters has been heated up to 130$^{\circ}$C and the extent of water-rock reaction was increased. At this point, pH of waters are increased, S04 concentration decreased and calcite precipitated, therefore, the waters show the $Na-S0_4$ type. 3) Ascending of the geothennal waters along the flow path of fluids and mixing with less-deeply circulated waters. The $S0_4$ concentration is re-increased due to the oxidation of $H_2S$ gas and/or sulfide minerals in sediments. During continuous ascending, these geothennal waters are mixed with shallow groundwater.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.94-102
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• 2008

The physico-chemical properties of ten reclaimed saline soils in five soil series of west-south Korea were analyzed according to the years past after reclamation. The soil samples were collected at the same sites two times in 2000 and 2004. The physico-chemical properties in 2000 had been changed in 2004 as follows. Soil salinity was the highest in Podu and desalinization period was the shortest in Munpo and Yeompo. Seasonal ground water level were above 100 cm in all regions that were 30 years old reclaimed tidal land, which was the same results of normal paddy field. In the case of soil physical changes, bulk density increased in fine textured soil (Poseung and Podu) but decreased in coarse textured soil (Gwanghwal, Munpo, and Yeompo). Porosity decreased in fine textured soil(Poseung and Podu) but increased in coarse textured soil. These reason were as follows. Fine textured soil were increased in solid phase but decreased in liquid and gaseous phase. Coarse textured soil, Gwanghwal and Munpo except for Yempo, were increased in gaseous phase but decreased in solid and liquid phase. Yempo that have low water table level were increased in liquid phase but decreased in solid and gaseous phase. Soil hardness increased in 4 soil series except for Munpo. In the case of chemical property changes, although there were more or less difference, it showed decreasing tendencies. Soil pH, the content of organic matter, available phosphate, and available silicate of five soil series were decreased during the four years. The content of exchangeable cation also decreased except for magnesium.

• Journal of the Mineralogical Society of Korea
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• v.20 no.1 s.51
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• pp.47-60
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• 2007

While sedimentological researches on Western coastal tidal flats of Korea have been much pelformed previously, mineralogical and biogeochemical studies are beginning to be studied. The objectives of this study were to investigate mineralogical characteritics of the inter-tidal flat sediments and to explore phase transformation of iron(oxyhydr)oxides and biomineralization by metal-reducing bacteria enriched from the inter-tidal flat sediments from Muan, Jeollanam-do, Korea. Inter-tidal flat sediment samples were collected in Chungkye-myun and Haeje-myun, Muan-gun, Jeollanam-do. Particle size analyses were performed using the pipette method and sedimentation method. The separates including sand, silt and clay fractions were examined by scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), and X-ray diffiaction (XRD). After enriching the metal-.educing bacteria from the into,-tidal flat sediments, the bacteria were used to study phase transformation of the synthesized iron (oxyhydr)oxides and iron biomineralization using lactate or glucose as the electron donors and Fe(III)-containing iron oxides as the electron accepters. Mineralogical studies showed that the sediments of tidal flats in Chung]rye-myun and Haeje-myun consist of quartz, plagioclase, microcline, biotite, kaolinite and illite. Biogeochemical researches showed that the metal-reducing bacteria enriched from the inter-tidal flat sediments reduced reddish brown akaganeite and mineralized nanometer-sized black magnetite. The bacteria also reduced the reddish brown ferrihydrite into black amorphous phases and reduced the yellowish goethite into greenish with formation of nm-sized phases. These results indicate that microbial Fe(III) reduction may play one of important roles in iron and carbon biogeochemistry as well as iron biomineralization in subsurface environments.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.168-178
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• 1994

Acid sulfate soils occur extensively in Gimhae area where they have been formed from the brackish alluvial sediments along the sea coast and river estuary. The strong acid environment enhances silicate weathering and thus affects the soil clay minerals. The minerals were identified through chemical, X-ray diffraction and thermal methods. The ratio of $SiO_2$ and $Al_2O_3$ in the clay fractions ranged from 3.14 to 3.77, indicating that the distribution of the clay minerals were 1 : 1 and 2 : 1 minerals. Cation exchange capacity in the clay fractions was low due to high contents of 1 : 1 minerals and hydroxy interlayered vermiculite(HIV). The B and C horizon rich in jarosite have large amounts of yellow streaks which reflect high content of $Fe_2O_3$ and $K_2O$. Vermiculite and illite were quantified from thermogravimetry(TG), kaolin minerals from both TG and differential thermal analysis(DTA), and HIV from X-ray diffraction analysis. The dominant clay minerals were kaolin minerals, vermiculite, illite and HIV. HIV considered to be formed, especially, in acid soil environments. The minor minerals were quarts, feldspar, jarosite, pyrite, hematite and goethite. Kaolin minerals were the most abundant clay minerals throughout the acid sulfate soil. Kaolin minerals, however, increased towards the top of horizons throughout the soils and HIV decreased towards the top of horizons in the soil of Gimhae series and Haecheog series. Alteration of HIV to kaolin minerals during weathering of low pH condition in deep soil horizons may explain the high quantities of kaolin minerals and the relatively low quantities of HIV in the soil at top horizons.