• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.7
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• pp.624-631
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• 2006

This study was conducted to make clustering analysis based on major physicochemical characteristics related to palatability of cooked rice. 89 Korea-bred japonica rice cultivars could be largely classified into two groups, that is, Dongjinbyeo and Ilpumbyeo groups. The Ilpumbyeo group was divided into two subgroups; Ilpumbyeo and Chucheongbyeo groups. The two major rice groups showed significant difference in viscogram properties of rice flour. Ilpumbyeo group revealed slightly higher estimates of viscogram traits as compared with Dongiinbyeo group in average. Early-maturing rice group showed slighly lower estimates of taste meter and higher protein content compared with medium or medium late maturing ones. Also, early and medium-maturing groups exhibited slightly higher estimates of peak, hot and breakdown viscosities but lower estimates of consistenency and setback viscosities compared with medium-late-maturing one. The rice cultivars developed in 2000's revealed slightly higher estimates of peak, hot, cool and consistency viscosities compared with those in $1980's{\sim}1990's$. The grain quality properties significantly associated with the esimates of Toyo taste meter were protein and amylose contents and hot viscosity. The lower protein content and hot viscosity and the higher amylose content, the higher estimates of the taster meter. The protein content was highly negatively correlated with amylose content of milled rice. The important quality components contributed to multiple regression formula for estimating the Toyo taster meter values were protein content, alkali digestion value, and hot viscosity. The fittness of this formula was about 49% along with the coefficients of determination.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.325-337
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• 2002

We examined the contamination of stream water and stream sediments by heavy metal elements with respect to distance from the abandoned Backun Au-Ag-Cu mine. High contents of heavy metals (Pb, Zn, Cu, Cd, Mn, and Fe) and aluminum in the waters connected with mining and associated deposits (dumps, tailings) reduce water quality. In the mining area, Ca and SO$_4$ are predominant cation and anion. The mining water is Ca-SO$_4$ type and is enriched in heavy metals resulted from the weathering of sulfide minerals. This mine drainage water is weakly acid or neutral (pH; 6.5-7.1) because of neutralizing effect by other alkali and alkaline earth elements. The effluent from the mine adit is also weakly acid or neutral, and contains elevated concentrations of most elements due to reactions with ore and gangue minerals in the deposit. The concentration of ions in the Backun mining water is high in the mine adit drainage water and steeply decreased award to down stream. Buffering process can be reasonably considered as a partial natural control of pollution, since the ion concentration becomes lower and the pH value becomes neutralized. In order to evaluate mobility and bioavailability of metals, sequential extraction was used for stream sediments into five operationally defined groups: exchangeable, bound to carbonates, bound to FeMn oxide, bound to organic matter, and residual. The residual fraction was the most abundant pool for Cu(2l-92%), Zn(28-89%) and Pb(23-94%). Almost sediments are low concentrated with Cd(2.7-52.8 mg/kg) than any other elements. But Cd dominate with non stable fraction (68-97%). Upper stream sediments are contaminated with Pb, and down area sediments are enriched with Zn. It is indicate high mobility of Zn and Cd.

• Economic and Environmental Geology
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• v.15 no.3
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• pp.123-154
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• 1982

Petrochemical, K-Ar dating, Sand Rb/Sr isotopes, metallogenic zoning, paleomagnetic and geotectonic studies of the Gyongsang basin were carried out to examine applicability of plate tectonics to the post-late Cretaceous igneous activity and metallogeny in the southeastern part of Korean Peninsula. The results obtained are as follows: 1. Bulgugsa granitic rocks range from granite to adamellite, whose Q-Ab-Or triangular diagram indicates that the depth and pressure at which the magma consolidated increase from coast to inland varying from 6 km, 0.5-3.3 kb in the coastal area to 17 km, 0.5-10 kb in the inland area. 2. The volcanic rocks in Gyongsang basin range from andesitic to basaltic rocks, and the basaltic rocks are generally tholeiitic in the coastal area and alkali basalt in the inland area. 3. The volcanic rocks of the area have the initial ratio of Sr^{87}/Sr^{86} varying from 0.706 to 0.707 which suggests a continental origin; the ratio of Rb/Sr changing from 0.079-0.157 in the coastal area to 0.021-0.034 in the inland area suggests that the volcanism is getting younger toward coastal side, which may indicate a retreat in stage of differentiation if they were derived from a same magma. The K_2O/SiO_2 (60%) increases from about 1.0 in the coastal area to about 3.0 in the inland area, which may suggest an increase indepth of the Benioff zone, if existed, toward inland side. 4. The K-Ar ages of volcanic rocks were measured to be 79.4 m.y. near Daegu, and 61.7 m.y. near Busan indicating a southeastward decrease in age. The ages of plutonic rocks also decrease toward the same direction with 73 m.y. near Daegu, and 58 m.y. near Busan, so that the volcanism predated the plutonism by 6 m.y. in the continental interior and 4 m.y. along the coast. Such igneous activities provide a positive evidence for an applicability of plate tectonics to this area. 5. Sulfur isotope analyses of sulfide minerals from 8 mines revealed that these deposits were genetically connected with the spacially associated ingeous rocks showing relatively narrow range of ${\delta}^{34}S$ values (-0.9‰ to +7.5‰ except for +13.3 from Mulgum Mine). A sequence of metallogenic zones from the coast to the inland is delineated to be in the order of Fe-Cu zone, Cu-Pb-Zn zone, and W-Mo zone. A few porphyry type copper deposits are found in the Fe-Cu zone. These two facts enable the sequence to be comparable with that of Andean type in South America. 6. The VGP's of Cretaceous and post Cretaceous rocks from Korea are located near the ones($71^{\circ}N$, $180^{\circ}E$ and $90^{\circ}N$, $110^{\circ}E$) obtained from continents of northern hemisphere. This suggests that the Korean peninsula has been stable tectonically since Cretaceous, belonging to the Eurasian continent. 7. Different polar wandering path between Korean peninsula and Japanese islands delineates that there has been some relative movement between them. 8. The variational feature of declination of NRM toward northwestern inland side from southeastern extremity of Korean peninsula suggests that the age of rocks becomes older toward inland side. 9. The geological structure(mainly faults) and trends of lineaments interpreted from the Landsat imagery reveal that NNE-, NWW- and NEE-trends are predominant in the decreasing order of intensity. 10. The NNE-trending structures were originated by tensional and/or compressional forces, the directions of which were parallel and perpendicular respectively to the subduction boundary of the Kula plate during about 90 m.y. B.P. The NWW-trending structures were originated as shear fractures by the same compressional forces. The NEE-trending structures are considered to be priginated as tension fractures parallel to the subduction boundary of the Kula plate during about 70 m.y. B.P. when Japanese islands had drifted toward southeast leaving the Sea of Japan behind. It was clearly demonstrated by many authors that the drifting of Japanese islands was accompanied with a rotational movement of a clock-wise direction, so that it is inferred that subduction boundary had changed from NNE- to NEE-direction. A number of facts and features mentioned above provide a suite of positive evidences enabling application of plate tectonics to the late Cretaceous-early Tertiary igneous activity and metallogeny in the area. Synthesizing these facts, an arc-trench system of continental margin-type is adopted by reconstructing paleogeographic models for the evolution of Korean peninsula and Japan islands. The models involve an extention mechanism behind the are(proto-Japan), by which proto-Japan as of northeastern continuation of Gyongsang zone has been drifted rotationally toward southeast. The zone of igneous activity has also been migrated from the inland in late-Cretaceous to the peninsula margin and southwestern Japan in Tertiary.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.20-27
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• 2001

Stream water chemistry in the abandoned Boeun Jeil coal mine area was studied for a period of 3 months, including rainy and dry season. The stream waters were a nearly neutral and slightly alkali condition, and $Mg-SO_4$ type with Mg>Ca>Na>K and $SO_4>HCO_3>Cl>NO_3$. Chemical composition of the stream water was quite irregular during the experimental period. Concentrations of Na, K, $HCO_3$, U, Sr, and Cr decreased by $10{\sim}30%$ during rainy season, caused by dilution effects with rain. The concentration of Ca, Mg, $NO_3$, Cd, and Co increased during the rainy season, caused by more easily dissolved from bedrocks or mine drainage with slightly acidic condition than dry season. The stream water was enriched in Mg, Ca, $HCO_3$, $SO_4$, Al, Fe, Zn, Ni, Co, Cr, Cd, Sr and U. Concentrations of Na, Mg, Ca, $SO_4$, $HCO_3$, Fe, Zn, Ni, Sr, and U decreased linearly with distance from the mine adit. These elements were strongly controlled by dilution of unpolluted water influx and/or adsorption on the clay minerals and iron oxyhydroxide precipitates. This mine area exhibited two main weathering processes ; 1) oxidation with acidification derived from Fe sulphides, and 2) pH buffering due to Ca and Mg carbonate dissolution. This weathering processes were followed by adsorption of metals on iron oxyhydroxides and precipitation.

• The Journal of Engineering Geology
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• v.8 no.3
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• pp.247-259
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• 1998

Groundwater quality of the natural mineral water was investigated in hydrochemical aspects in order to ensure that mineral water meets stringent health standards. There exist 20 mineral water plants in the Daebo granite and 4 mineral water plants in the Bulguksa granite, respectively. Both granite areas show some differences in water chemistry. The pH, EC, hardness, total ionic contents in groundwater of the Daebo granite area are higher relative to those of the Bulguksa granite area. The content of major cations is in the order of Ca>Na>Mg>K, while that of major anions shows the order of $HCO_3>SO_4$>Cl>F. The fact that the $Ca-Na-HCO_3$ type is most predominant among water types may reflect that the dissolution of plagioclase that is most abundant in granitic rocks plays a most important role in groundwater chemistry. Representative correlation coefficients between chemical species are variable depending on geology. In the Daebo granite area, $Ca-HCO_3(0.84),{\;}Mg-HCO_3(0.81),{\;}SiO_2-Cl(0.74),{\;}Na-HCO_3(0.70)$ show relatively good correlationships. In the Bulguksa granite area, fairly good correlationships are found among some components such as K-Mg(0.93), $K-HCO_3(0.92)$, Mg-Cl(0.92), $Cl-HCO_3(0.91)$, and K-F(0.90). According to saturation index, most chemical species are undersaturated with respect to major minerals, except for some silica phases. Groundwater is slightly undersaturated with respect to calcite, whereas it is still greatly undersaturated with respect to dolomite, gypsum and fluorite. Based on the phase equilibrium it is clear that groundwater is mostly in equilibrium with kaolinite and becomes undersaturated with respect to feldspars, evolved from the stability area of gibbsite during water-rock interaction. While the activity of silica increases, there is no remarkable increase in the acivities of alkali ions and pH, which indicates that some amounts of silicic acid dissolved from silica phases as well as feldspars were provided to groundwater. It is concluded that chemical evolution of groundwater in granite aquifers may continue to proceed with increasing pH.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.2
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• pp.203-216
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• 2008

This study was conducted to provide the fundamental data based on the analysis of phsyco-chemical characteristics of domestic aroma rice and foreign aroma rice for breeding of aroma rice. The average amylose content of domestic aroma rice and widely cultured domestic traditional rice were 18.1% and 19.0% respectively. The Indica and the Japonica types were 25.6% and 25.0%. In the domestic rice of Tongil and Japonica type, the average protein content were 7.6% and 6.4% respectively. And the average protein content of foreign Indica and Japonica type were 7.6% and 7.0% respectively. And the average protein content of widely cultured domestic traditional rice was 5.6%. The Japonica type of rice shown a low protein content compared with Indica type of rice, and the foreign Indica types of rice exhibited a wide range of protein contents. The average alkali digestive value (ADV) of Tongil type of the domestic aroma rice was about 5.0 and the value of Japonica type was about 6.0. The average ADV of foreign Indica and Japonica type were 4.3 and 5.1 respectively. Also the average ADV of widely cultured domestic aroma rice was about 6.0. The foreign aroma rice were distributed a variable range of ADV value and lower than the both domestic aroma rice and widely cultivated domestic rice. In the whole aspect of the amylogram, the highest viscosity, the lowest viscosity and the last viscosity of the total resources, in domestic aroma rice were clearly lower with the next order, Japonica type of foreign aroma rice, Indica type of foreign aroma rice, Japonica type of domestic aroma rice, widely cultured domestic traditional rice, and Tongil type of domestic aroma rice. It shown the difference aspect of amylograms according to the eco-type of the domestic and foreign aroma and the general rice, and it was distinguishable in difference of the aspect of the amylogram of the endosperm of rice as non-glutinous rice, waxy rice, and middle-waxy rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.274-282
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• 2013

This study was carried out to find out the physicochemical properties of rice grains of 8 varieties having various amylose content. Amylose contents of 8 varieties were ranged from 6.3 to 30.9% and could be classified into 4 groups, such as waxy, low-amylose, nonglutinous, and high-amylose. Protein contents were ranged from 5.8% to 7.5% varied depending on variety, but there was no significant difference in protein contents among groups. The hardness of milled rice grains in low-amylose and non-glutinous was stronger than waxy and low-amylose group. Whiteness of waxy group grains was the highest while non-glutinous group was the lowest. The alkaline digestive values were evenly distributed from 5.2 to 6.9 and highly correlated with amylose content. There was significant difference in pasting properties of rice flours among groups. High-amylose group showed the highest initial pasting temperature and total setback viscosity, and the lowest peaks for trough and breakdown viscosity. Low-amylose group showed the highest breakdown viscosity but the lowest setback viscosity as well as high peak viscosity. Although amylose content was significantly correlated with alkali spreading value in milled rice, initial pasting temperature, and total setback, but it was negatively correlated with toyo-meter value and setback viscosity.

• Journal of the Speleological Society of Korea
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• no.74
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• pp.23-31
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• 2006

(1) Kaeusetgul Cave in Kimnyong-Ri, Jeju-Do, Korea. Kaeuset-gul Cave (KC) is situated in NNE area of the Manjang-gul cave (125m a.s.l.). Kaeuset-gul Cave lies at $126^{\circ}45'22"$ E in longitude and $33^{\circ}33'09"$ N in latitude. The coast belong Kimnyeong-Ri, Kujwa-eup, Jeju-Do. Altitude of the cave-entrance is 10m and length of the cave is 90m. Lava hand-specimens of KC are studied by X-ray fluorescence analysis (XRF). Average major chemical components of specimens from KC is as follows (wt.%); $SiO_2=47.03$, $TiO_2=3.16$, $Al_2O_3=18.41$, FeO*=13.53, MnO=0.14, MgO=5.05, CaO=8.66, $Na_2O=2.81$, $K_2O=0.67$, $P_2O_5=0.55$ in KC. Polarizing microscopic studyindicates that these specimens are described of alkali-basalt. (2) Tachibori Fuketsu (Cave) in Shizuoka Prefecture, Fuji Volcano, Japan Tachibori Fuketsu lies attoward the south in skirt of the Fuji volcano, $138^{\circ}42'04"$ east longitude and $35^{\circ}18'00"$ north latitude. The location of cave entrance is 2745, Awakura, Fujinomiya-shi, Shizuoka Prefecture. The above sea level and length of Tachibori Fuketsu are 1,170m and 82m. Average major chemical components of specimens from cave areas follows (Total 100 wt.%) ; ($SiO_2$=50.52, $TiO_2$=1.69, $Al_2O_3$=15.47, FeO*=13.13, MnO=0.20, MgO=5.97, CaO=9.17, $Na_2O$=2.52, $K_2O$=0.94 and $P_2O_5=0.40).$ Polarizing microscopic study indicates that these specimens may belong to tholeiite-basalt series. According to polarizing microscopic study, Au (Augite), P1 (Plagioclase), and O1 (Olivine) are contained as phenocryst minerals. (3) Gorely Cave in Kamchatka Peninsula, Russia Gorely caldera is located at the southeastern part of Kamchatka Peninsula, about 75km southwest of Petropavlovsk-Kamchatskiy.. Gorely lava caves are situated in NHE area of Mt. Gorely volcano (1829m a.s.1.). One of lava cave (Go-9612=K-1) lies at $158^{\circ}00'22"$ east longitude and $52^{\circ}36'18"$ north latitude. The elevation of cave entrance is about 990m a.s.1. and the main cave extends in the NNW direction for about 50m by 15m wide and 5m in depth. The cave of K-3is near the K-1 cave. "@Lava hand-specimens K-1 and K-3 caves are studied by X-ray fluorescence analysis and polarizing microscopic observation. Average major chemical components of specimens from these caves are as follows (wt.%) ;($SiO_2$=55.12, $TiO_2$=1.25, $Al_2O_3$=16.07, T-FeO* =9.41, MnO=0.16, MgO=5.01, CaO=7.21, $Na_2O$=3.39, $K_2O$=1.92, $P_2O_5$=0.45) and these values indicate that the Gorely basaltic andesite belong to high alumina basalt. Polarizing microscopic study indicates that these specimens are described of Augite andesite.

• The Journal of the Petrological Society of Korea
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• v.6 no.2
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• pp.77-85
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• 1997

The Early Proterozoic reworked rock association occurs within the Preacmbrian high grade metamorphic rocks in the area of Daqingshan, Inner Molgolia. In this association, the various large scale ductile deformation belts, form a nappe structure where the foliation steeply dips to north and the lineation ($340^{circ}-30^{\circ}$) plunges at $45^{\circ}55^{\circ}$. This result indicates the subduction/extension with northern part thrusting over the southern part at high angle. The southern subducted microlithon has the characteristics of prograde metamorphism. The northern thrusted microlithon shows the evidence of retrograde metamorphism with decreasing pressure and increasing temperature. The main rock types of Early Proterozoic Moyites are biotite adamellite and syenogranites occurring in the form of small batholiths or stocks and alkali-feldspar granites in veins. The biotite adamellites are progressively contacted with the Archean and Early Proterozoic rocks and contain a great deal of enclaves of metamorphosed rocks, suggesting an anatexis origin. The geochemical characteristics of moyites show the typical features of anatexis granite. At middle to late Early Proterozoic time, the continent-continent collision formed the large scale thrusting and imbrication of Archean basement rocks. According to the mineral assemblage and thermobarometer of Paria et al. (1988) give the following P-T condition : up-faulted block; $700-710^{\circ}C$, 0.72-0.78 Gpa (early stage) and $600^{\circ}C$, 0.44 Gpa (late stage), footwall block; $620^{\circ}C$, 0.8 Gpa (early stage), $620-840^{\circ}C$, 0.64-0.45 Gpa (peak) and $620-630^{\circ}C$, 0.35Gpa (late stage). These results suggest a clockwise P-T-t path (jin et al., 1991, 1994). According to the depth-temperature model in the comperature subduction zone and the experimental data of Wyllie et al. (1983), we propose a tectonic-magmatic-thermal model to account for metamorphism-anatexis of moyite occurring in subduction-shear zone.

• The Journal of the Petrological Society of Korea
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• v.24 no.1
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• pp.25-54
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• 2015

Syenite is not a common rock, unlike granitic rocks formed the major component of the continental crust. The aim of this study is to decipher the occurrences and detailed descriptive characteristics of the syenite distributed in Sancheong area, and to investigate the petrogenesis of the syenitic magma based on geochemical study. The dominant minerals in syenite are alkali feldspar (usually orthoclase and rarely microcline), plagioclase, amphibole, biotite, and quartz. Syenites are found in a wide variety of colors. The anhedral hornblende and biotite filling the boundary of feldspar and quartz indicate that the hydrous minerals were crystallized lately, and that water was insufficient at the beginning of crystallization in magma. According to the analysis of mineral composition, amphibole in syenite is mostly ferro-edenite, and the pressure is calculated as 3.3~4.9 kb with 11.9~17.3 km of emplacement depth. Biotite and pyroxene are plotted in the region of annite and hedenbergite, respectively. Based on petrochemical studies of major elements, syenite belongs to alkaline series, metaluminous, and I-type. On the other hand, the variation patterns of trace and rare earth elements of syenite differ from the patterns of diorite and granite. In the geochemical characteristics, syenite is different from gabbro-diorite spatially adjacent to syenite, as well as granite. These results suggest that each rock has been generated from the different sources of magma. Additionally, based on the experimental data, the syenitic magma can be formed (1) by the partial melting at a high pressure and dry system, (2) when the initial crystallization minerals to be residue with migration of the residual melts separated from the ascending cotectic magma (3) when fluorine compositions to be plentiful in the protolith and/or at depth of the magma. Based on the petrographic characteristics of the syenite, Sancheong syenitic magma may have been formed by partial melting in a dry system.