• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.263-263
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• 2017

Rice (Oryza sativa L.) is the world's third largest food crop after wheat and corn. Geographic authentication of rice has recently emerged as an important issue for enhancing human health via food safety and quality assurance. Here, we aimed to discriminate rice from six Asian countries through geographic authentication using combinations of elemental/isotopic composition analysis and chemometric techniques. Principal components analysis could distinguish samples cultivated from most countries, except for those cultivated in the Philippines and Japan. Furthermore, orthogonal projection to latent structure-discriminant analysis provided clear discrimination between rice cultivated in Korea and other countries. The major common variables responsible for differentiation in these models were ${\delta}^{34}S$, Mn, and Mg. Our findings contribute to understanding the variations in elemental and isotopic compositions in rice depending on geographic origins, and offer valuable insight into the control of fraudulent labeling regarding the geographic origins of rice traded among Asian countries.

• Journal of the Mineralogical Society of Korea
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• v.29 no.3
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• pp.141-153
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• 2016

The Manjang deposit is emplaced in Hwajeonri formation comprising limestone that is interbeded with slate and phyllite in the central Okcheon Group. It consists of the Main and the Central orebody of Cu-bearing hydrothermal vein deposit and the Western orebody of iron skarn deposit. Based on coexisting mineral assemblage the skarnization can be divided into prograde skarnization (stage I : clinopyroxene ${\pm}$ magnetite ${\pm}$ quartz, stage II : garnet + clinopyroxene ${\pm}$ magnetite ${\pm}$ quartz) and retrograde hydrothermal alteration (stage III: magnetite + amphibole + quartz ${\pm}$ garnet ${\pm}$ clinopyroxene ${\pm}$ chlorite ${\pm}$ epidote ${\pm}$ fluorite ${\pm}$ calcite, stage IV: fluorite ${\pm}$ pyrrhotite ${\pm}$ chalcopyrite ${\pm}$ amphibole ${\pm}$ quartz ${\pm}$ calcite). Diopside is abundant in stage I, and hedenbergite was produced in stage II and III. Garnet compositions change from grandite to andradite, which suggests a redox transition from relatively reduced to oxidized condition during the skarn formation. Magnetite in stage I and II has relatively constant Fe contents, while in the stage III it has increased Si and Ca concentrations. This variation could indicate that magnetite was more strongly affected by host rocks during the retrograde stage. Sulfur isotope compositions of pyrrhotite and chalcopyrite produced in stage IV are within the range of + 5.9~6.9 ‰, corresponding to igneous origin, but slightly high sulfur isotope values could be attributed to an interaction with host rocks, limestone.

• Journal of Conservation Science
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• v.25 no.3
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• pp.335-345
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• 2009

This paper presents investigations on 60 glass beads excavated from floorless tombs of Eunpyeong Newtown site to figure out composition and lead isotope ratio by SEM-EDS and TIMS, which show the difference between their compositions and Pb provenance of lead glass. The results of the composition analysis are that excavated glass are mainly divided into Potash glass($K_2O$-CaO-$SiO_2$) and Potash-lead glass($K_2O$-PbO-$SiO_2$) and the samples excavated from III-3 floorless tombs No.1005 are presumed not glass but Quartz. The transparent 9 lead glasses excavated from II-3 floorless tomb No.101 and III-3 floorless tomb No.908 seem to be manufactured by the same raw material at same site because the concentration of their compositions are well accorded with each other and deviations of them are very limited. As a result of principal component analysis(PCA), glass beads excavated are largely assort to two groups, Potash glass and Potash lead glass as well. That is, glass beads excavated from Eunpyeoung Newtown sites are quite different two types of main composition. In addition, the results of Pb provenance analysis used in lead glass confirm that most lead glass are significantly correlated with galena of northern China.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.spc1
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• pp.189-197
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• 2006

To elucidate the organic matter sources in soft-bottom macrozoobenthos at Tongyeong, Korea, macrozoobenthos and their potential food sources were sampled in May 2004, and their C and N stable isotope compositions were analyzed. In total we collected 128 macrozoobenthic species, which ranged from 465 to 3,775 individuals/$m^2$(average 2,108 ind.$m^2$) in density and from 47.8 to 539.9 gwwt/$m^2$(average 366.0 gwwt/$m^2$) in biomass. Cluster and multi-dimensional scaling analyses indicated that the macrozoobenthic community was divided into two distinct groups. Coastal inner stations, where commercial fish cages were established, were dominated by Amphioplus ancistrotus, Scoletoma longifoila and Tharyx sp., whereas open sea stations were dominated by Chaetozone spinosa, Scoletoma longifolia and Capitella capitata. ${\delta}^{13}C$ values of sedimentary organic matter showed a distinct gradient in the range of -18.4 to $-15.2\%_{\circ}$, with a declining trend from the coastal inner stations to open sea stations. This probably reflects the settling rate of organic wastes such as feces and pellets from fish cages near the coastal inner stations. The macrozoobenthos showed a broad ${\delta}^{13}C$ range from -19.5 to $-8.9\%_{\circ}$ at the coastal inner stations, and a relatively narrow range from -21.3 to $-12.9\%_{\circ}$ at the open sea stations. ${\delta}^{13}C$ values of macrozoobenthos paralleled those of sedimentary organic matter, Our isotope results suggested that macrozoobenthos near the coastal inner stations used organic wastes derived from fish cages along with phytoplankton, whereas the macrozoobenthos near the open sea stations used organic wasters derived mainly from phytoplankton.

• Economic and Environmental Geology
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• v.25 no.1
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• pp.41-50
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• 1992

Mineral assemblages, mineral chemistries and stable isotope compositions of altered rocks of the Ogmae, Seongsan, Haenam and Gusi mines near the Haenam volcanic field in the southwestern part of the Korea peninsula were studied. Characteristic hydrothermal alteration zones in these deposits occurring in the Cretaceous volcanics and volcanogenic sediments, acidic tuff, and rhyolite, were outlined. Genetic environment with particular reference to the spatial and temporal relationships for these deposits were considered. The alteration zones defined by a mineral assemblage in the Ogmae and Seongsan deposits can be classified as alunite, pyrophyllite, kaolinite or dickite, quartz, illite or illite/smectite. Alunite was not developed in the Gusi and Haenam deposits. Boundaries between the adjacent zones are always gradational except for vein-type alunite. Alteration zones are superimposed upon each other in some localities. These deposits formed $71.8{\pm}2.8{\sim}76.6{\pm}2.9$ Ma ago, which is the almost same age of later volcanic rocks $79.4{\pm}1.7{\sim}82.8{\pm}1.2$ Ma, the Haenam Group, corresponding to Campanian. It indicates that hydrothermal alteration of these deposits appeared to be related to felsic volcanism in the area. Consideration of the stability between kaolinite, alunite, pyrite and pyrophyllite, and the geothermometry based on the mineral chemistry of illite and chlorite suggests that the maximum formation temperature for alunite and pyrophyllite can be estimated at about $250^{\circ}C$ and $240{\sim}290^{\circ}C$, respectively. It also suggests that these deposits were formed by acidic sulfate solution with high aqueous silica and potassium activity in a shallow depth environment. Compositional variation of alunite also suggests that the physico-chemical conditions fluctulated considerably during alteration processes, indicating shallow depth environment. The Haenam deposit was formed at a relatively greater depth than the others. The sulfur isotope composition of alunite and pyrite indicates that sulfur probably had a magmatic source, and the oxygen isotope composition for kaolinite indicates that the magmatic hydrothermal solution was diluted by circulating meteoric water.

• Economic and Environmental Geology
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• v.18 no.3
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• pp.247-251
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• 1985

The sulfide and carbonate mineral samples for sulfur and carbon isotope studies were collected from Sangdong, Geodo, Yeonhwa, Shinyemi and Janggun mines which are distributed in the Metallogenetic Province of the Taebaeg Mt. Region. The ${\delta}S^{34}$ values of molybdenite, pyrite, arsenopyrite, pyrrhotite, chalcopyrite, sphalerite and galena from the above mines are similar and within the range of +1.66 to +6.77‰ with the exception of chalcopyrite from Geodo mine ranging from -1.58 to 1.96‰, while the sulfide minerals are dominated by positive values between +3.05 and +5.08‰. It is suggested that the major sulfur source is genetically related to the Cretaceous granitic activity. The average ${\delta}C^{13}$ values of calcite from limestone, calcite from calcite vein in ore bodies and granite, and rhodochrosite from ore bodies are -0.60‰, -2.69‰ and -6.00‰, respectively. The data on carbon isotope compositions indicate that the calcite from limestone originated in marine environment, the rhodochrosite in hydrothermal solution, and calcite from calcite vein and granite in the mixing condition of marine and hydrothermal waters. The temperatures of mineralization by the sulfur isotopic composition coexisting pyrite-pyrrhotite from Yeonhwa No.1, sphalerite-galena from Weolam and Dong-jeom of Yeonhwa No.1 mine, sphalerite-galena and pyrite-galena from Janggun mine were $273^{\circ}C$, $460{\sim}511^{\circ}C$, $561{\sim}690^{\circ}C$, $341^{\circ}C$ and $375^{\circ}C$, respectively.

• Journal of Conservation Science
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• v.19
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• pp.67-72
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• 2006

The chemical compositions and lead isotope ratio of Poong-Tag(wind bell) bell excavated from Wanggyeong site, Gyeongju have analyzed by ICP and TIMS. The analysis result of chemical composition of Poong-Tag shows that it consists of 92:4 ratio of Cu:Sn. Other 8 minor elements(Pb, Zn, Fe, Ag, Ni, As, Sb and Co) show the concentration of below 0.2% respectively. This result means that Poong-Tag have made using highly purified Cu and Sn ore. For the study of provenance of raw material with the lead isotope ratio, the origin of the raw material of Poong-Tag can not be presumed owing to beyond the scope. The observation result of microstructure of Poong-Tag show the dendrite structure made through casting process. The chemical composition, microstructure, and lead isotope ratio of Poong-Tag excavated from Wanggyeong site, Gyeongju can be used as fundamental data to compare with other Poong-Tag of different regions and periods.

• The Journal of the Petrological Society of Korea
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• v.14 no.3 s.41
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• pp.127-140
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• 2005

The Samyuri area of Jeoksang-myeon, Muju-gun at the Middle Yeongnam Massif consists of granitic gneiss, porphyroblastic gneiss and leucocratic gneiss, which correspond to Precambrian Wonnam Series. Here we discuss a geochemical implication of the data based on major element composition, trace element, rare earth element (REE), Sm-Nd and Rb-Sr isotope systematics of the boring cores in the granite gneiss area. The boring cores are granitic gneiss (including biotite gneiss) and amphibolite. The major and trace element compositions of granitic gneiss and amphibolite suggest that the protolith belongs to TTG (Tonalite-Trondhjemite-Granodiorite) and tholeiitic series, respectively. Chondrte-normalized REE patterns vary in LREE, HREE and Eu anomalies. The granitic gneiss and amphibolite have Sm-Nd whole rock age of $2,026{\pm}230(2{\sigma})$ Ma with an initial Nd isotopic ratio of $0.50979{\pm}0.00028(2{\sigma})$ (initial ${\epsilon}_{Nd}=-4.4$), which suggests that the source material was derived from old crustal material. Particularly, this initial ${\epsilon}$ Nd value belongs to the range of the geochemical evolution of Archean basement in North-China Craton, and also corresponds to the initial Nd isotope evolution line by Lee et al. (2005). In addition, chondrite-normalized REE pattern and initial Nd value of amphibolite are very similar to those of juvenile magma in crustal formation process.

• Korean Journal of Heritage: History & Science
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• v.36
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• pp.241-266
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• 2003

Glass pieces excavated from Mireuksa Temple dated $7^{th}$ century A.D. were characterized by chemical composition, specific gravity and melting point. Lead isotope ratios of lead glasses were also compared with those of lead ore to attribute which lead ore was delivered for making lead glass. It was known that some lead glasses found in Japan were similar with those of Mireuksa Temple as comparing the data of chemical composition and lead isotope ratios. Characteristics of lead glass from Mireuksa Temple Thirty five glass pieces of Mireuksa Temple were analyzed for five oxides and found that all was lead glass system(PbO-$SiO_2$) with the range of 70~79% for PbO and 20~28% for $SiO_2$. The concentrations of oxides such as $Al_2O_3$, $Fe_2O_3$ and CuO were below 0.4%, 0.3% and 0.9%, respectively. Principal component analysis(PCA) as a statistical method was carried out to classify glasses with the similarities of chemical concentrations. The result of PCA has shown that three groups of glasses were created according to the excavation positions and two major oxides(PbO and $SiO_2$) greatly contributed to the dispersion of glasses on principal component 1(PC1) axis and trace element oxides($Al_2O_3$ and $Fe_2O_3$) for PC2 axis. Most of lead glasses were greenish by the efficacy of iron and copper oxides and some showed yellowish-green. The gravity of lead glasses was about 4.4~5.4 and estimated melting point was near $670^{\circ}C$. Lead isotope ratios of glasses were analyzed and found quite close to a lead ore from the Bupyeong mine in Gyeonggi-do. Comparison with lead glasses found in Japan Lead glasses of Mireuksa Temple were compared with those of Japan on the basis of chemical and physical data. Chemical compositions of Japanese lead glasses dated $7^{th}{\sim}8^{th}$ century A.D. were nearly similar with those of Mireuksa Temple but lead isotope ratios of those were separated into two groups. Three distribution maps of lead ores of Korea, Japan and China with lead isotope ratios were applied for lead glasses found in Japan. The result have shown that the locations of lead glasses from Fukuoka Prefecture coincided with the region of northen part of Korea and similar with those of Mireuksa Temple and lead glasses from Nara Prefecture dated $8^{th}$ century A.D. were located in the region of Japanese lead ore. This research has demonstrated that lead glasses of Mireuksa Temple conveyed to Miyajidake site, Fukuoka Prefecture around $7^{th}$ century A.D. and glass melting pots and glass beads excavated from Nara Prefecture confirmed the first use of Japanese lead ore for production of lead glasses from the end of $7^{th}$ century A.D.

• The Journal of the Petrological Society of Korea
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• v.19 no.3
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• pp.181-197
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• 2010

This study is for finding a geoscientific factor for clarifying the source soil of the ancient earthenware finding. The used samples were the earthenware, soil and rocks, which were collected at the Gyeongju, Gyeongsan and Haman area. The chemical and mineralogical study for the samples were carried out for understanding the change of mineralogical and chemical composition among them. The mineralogical compositions of the earthenware are different from those of the soils from the surrounding area, which suggests that the mineralogical approach for clarifying the source soil of the earthenware should be difficult. Major element compositions of the earthenware also are different from those of the surrounding soils, which suggests that the comparison of the chemical composition using the major elements might be difficult for deducing the source soil of the earthenware. However, PAAS-normalized rare earth element (REE) patterns and Nd model ages among the rock, soils and earthenware from the same sampling sites show similar characteristics one another compared to those of the major element compositions. Nd-Sr isotopic systematics among the earthenware, soils and rocks also show a close relationship. Our results suggest that REE and Nd-Sr isotope geochemistry might be more useful than the other geochemical technique in clarifying the source soils of the ancient earthenware.