• The Journal of the Petrological Society of Korea
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• v.17 no.2
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• pp.108-131
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• 2008

The Miocene andesite and basalt intruded into and/or extruded on the Cretaceous volcanic and granitic rocks over the area of Chenjabong and Sirubong in the vicinity of Jinhae, southern part of Kyongsang basin. The K-Ar ages of the younger volcanic rocks are from 16 Ma (Sirubong andesite) to 10 Ma (Cheonjabong basalt), which indicate the Miocene volcanism in the outer part of the Tertiary basin in the Korean peninsula. The volcanics are divided into Chenjabong andesite, Cheonjabong basaltic andesite, Sirubong andesite and Cheonjabong basalt. The Cheonjabong andesite is composed of phenocrysts of clinopyroxene and plagioclase ($An_{60{\sim}64}$) and groundmass with lath-like plagioclase ($An_{76{\sim}84}$) and glass. The Cheonjabong basaltic andesite is composed of plagioclase phenocryst ($An_{60{\sim}64}$) with plagioclase lath ($An_{65}$) and glass in groundmass. The Sirubong andesite is only consisted of plagiocalse lath ($An_{64{\sim}68}$) and glass with absence of phonocryst. The Cheonjabong basalt shows typical porphyritic texture with phenocrysts of olivine ($Fo_{69-84}$) and clinopyroxene. The groundmass of the Cheonjabong basalt is composed of microphenocrysts of olivine, clinopyroxene and plagioclase ($An_{66{\sim}71}$) and plagioclase laths ($An_{57{\sim}65}$) showing pillotaxitic and intergranular texture. The Cheonjabong andesite, Cheonjabong basaltic andesite, Sirubong andesite are belong to calc-alkialine but the Cheonjabong basalt is alkaline basalt. By tectonic discrimination diagrams the parental magmas of the volcanic rocks have occurred boundary.

• The Journal of the Petrological Society of Korea
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• v.9 no.2
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• pp.99-118
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• 2000

The variation of Na(A), K, Na(M4), A l O and Al(VI)+Fe3++Ti+Cr in the zonal amphiboles from the amphibolites of the Hwanggangri area indicates that the tschermakite-, edenite- and glaucophane substitutions are higher in the rim than in the core, in which actinolite changes to hornblende with going outward from core to rim. The contents of substitutional elements of hornblende~ of three samples@l29-2, M76-2, M78), which include diopside and greenish brown hornblende and are thought to represent the highest metamorphic grade, are lower than those of rim homblendes of the lower metamorphic grade and are higher than those of core actinolite that they conform to the middle domain in those of the whole amphiboles. Considerations about the origin of zonal amphiboles are as follows. Firstly, two samples(R102-1, R210-9) have the same amphibole composition like core is actinolitic hornblende, and rim is magnesian hastingsite although plagioclases such as albite(R102-1) and labradorite (R210-9) show the wide compositional difference. It is impossible to produce both albite and labradorite by one metamorphic event. Judging from this wide compositional difference, the existence of zonal amphiboles does not indicate the miscibility gap but is thought to be the result of the polymetamorphism. Secondly, the crystallographically sharp and gradational interfaces between actinolite and hornblende fonned in the amphibolites rgardless of the distance from the granite. In case of the samples(R210-9, M128, M130) having the sharp interface between two amphiboles, the plagioclase show the compositions produced at the low grade and the medium grade. Because such variable compositions of plagioclase indicates the overprinting of metamorphism of higher metamorphic grade than that of the formation of miscibility gap, it implies that zonal amphiboles were formed by polymetarnorphism. In case of the gradational interface between two amphiboles, this texture is also thought to be the effect of polymetamorphism from the fact that this texture mainly occur near the granite and from the consideration of the metamporphic grade. The relationship between the compositional variations of the amphiboles and the pressure types of metamorphism suggests that actinolitic core is considered to be grown by the metamorphism of medium pressure, while hornblende rim is shown to have genetic relations with the metamorphism of low pressure type.

• The Journal of the Petrological Society of Korea
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• v.9 no.2
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• pp.84-98
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• 2000

Daejeon-sa basalt in the Mt. Juwang area composed of 12 basalt flows alternate with 9 peperites and each basalt and peperite has the variety of thickness. Peperites yielded in Daejeon-sa basalt are mixed of basalt with reddish shale, of which textural type is globular peperite. Basalts yielded in Daejeon-sa basalt are massive basalt without vesicule, although sometimes vesicules are founded in upper within a flow unit. The basalt has mainly pseudomorph of olivine as phenocryst, and also plagioclase and clinopyroxene phenocryst. Matrix is mainly subophitic texture. The plotting result on the TAS diagram shows these basalts belong to the sub-alkaline, and it can be subdivided into calc-alkaline series on the basis of the diagram of Si02 vs. K20 and of alkali index vs. A1203 diagram. According to plots of wt.% oxides vs. wt.% MgO, abundances of A1203 and CaO increase with decreasing MgO while F ~ dOecre~ase . With decreasing MgO compatible elements decrease while incompatible elements increase. In spider diagram of MORB-normalized trace element patterns, HFS elements are nearly similiar with MORB, but LIL elements are enriched. Especially, contents of Ce, F: and Sm are enriched but Nb is depleted. In the chondrite-normalized REE patterns light REEs are enriched than heavy REEs. Tectomagmatic discrimination diagrams shows basalts in the study area are formed in the tectonomagmatic environment of subduction zone under continental margin. This result accord with characters of chemical composition mentioned above. Cr vs. Y diagram and CeM, vs. Ce diagram show that the primary magma of the basalts may formed by the about 15% partial melting of garnet-peridotite in the mantle wedge. After then, Daejeon-sa basalts may formed from evolved magma undergone mainly olivine fractional crystallization and contarnination of crustal materials before eruption.

• Journal of the Mineralogical Society of Korea
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• v.7 no.1
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• pp.49-61
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• 1994

As the groundwater flows along the fractures of crystalline rocks, it will be in contact with the fracture walls mostly coated by secondary minerals which are quite different form those of host rocks. The presence of fracture-filling minerals in crystalline rocks is important on the view point of radioactive waste disposal because of their great surface reactivity. The Surichi drill hole of 200 m in depth in the Yugu area composed mainly of Precambrian gneiss was selected to study the formation process of clay minerals on the fracture wall of gneiss, and their relation with present groundwater. The water-rock interaction in fractures resulted in the formation of gibbsite and clay minerals. They are formed by two different processes : (1) Incongruent dissolution of feldspar by groundwater diffused from a fracture path into rock matrix produced smectite and illite in situ, (2) on the wall of fracture, gibbsite, kaolinite, smectite and illite are formed by precipitation of dissolved species in groundwater. They show the paragenetic sequence such as gibbsite${\leftrightarrow}$kaolinite${\leftrightarrow}$smectite or illite. The paragenetic sequence of fracture-filling minerals was controlled by increase of pH of groundwater, decrease of fracture permeability by precipitation of fillings, and immobility of alkali or alkaline earths in groundwater. The groundwater from the Surichi borehole is a $Na-HCO_{3}$ type with pH range of 8.6-9.2. The sodium and bicarbonate in groundwater would be supplied by the dissolution of albite and calcite, respectively. The saturation index of groundwater and surface water calculated by WATEQ4F indicates that gibbsite and kaolinite are under precipitation to equilibrium state, and that smectite and illite are under equilibrium to redissolution environment. The stability relation of clay minerals in the $Na_{2}O-Al_{2}O_{3}-SiO_{2}-H_{2}O$ system shows that kaolinite is stable for all waters.

• Journal of the Korean earth science society
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• v.34 no.4
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• pp.313-328
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• 2013

Jurassic granitoids in the northeastern part of the Yeongnam Massif are possibly the result of intensive magmatic activities that occurred in response to subduction of the proto-Pacific plate beneath the northeast portion of the Eurasian plate. Geochemical studies on the granitic rocks are carried out in order to constrain the petrogenesis of the granitic magma and to establish the paleotectonic environment of the area. Whole rock chemical data of the Uljin granitoids in the northeastern part of the Yeongnam Massif indicate that all of the rocks have the characteristics of calcalkaline series in subalkaline field. The overall major element trends show systematic variations in each granitic body, but the source materials of each granitoids seem to have different chemical composition. The Uljin granitoids are different from other granitic rocks, which distributed vicinity of the study area, in the contents of $Al_2O_3$ and trace elements such as Cr, Co, Ni, Sr, Y and Nb. The Uljin granitoids have geochemical features similar to slab-derived adakites such as high $Al_2O_3$, Sr contents and high Sr/Y, La/Yb ratios, but they have low Y and Yb contents. The major ($SiO_2$, $Al_2O_3$, MgO) and trace element (Sr, Y, La, Yb) contents of the Uljin granitoids fall well within the adakitic field. The Uljin granitoids have similar geochemical characteristics, paleotectonic environments and intrusion ages to those of the Yatsuo plutonic rocks of Hida belt located on northwestern part of Japan. Chondrite normalized REE patterns show generally enriched LREEs ($(La/Yb)_{CN}=10.6-103.4$) and are slight negative to flat Eu anomalies. On the ANK vs. A/CNK and tectonic discrimination diagrams, parental magma type of the granites corresponds to I-type and volcanic arc granite (VAG). Interpretations of the chemical characteristics of the granitic rocks favor their emplacement in a compressional tectonic regime at the continental margin during the subduction of Izanagi plate in Jurassic period.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.441-449
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• 1996

This study was conducted to find the changes of growth, seed yield and several characteristics of sesame by leaf spray of boron as a solution which is likely to be lack in the soil. It is carried out at low land developed 5 years ago. The amount of 200l /l0a boron as boric acid is sprayed in each treatment at the 11 node stage of sesame in main stem. The spraying concentrations of boric acid are 0.0, 0.2 and 0.4% in each treatment of the level low plot and the ridge height 15cm plot. The result shows that leaf area is increased in proportion to the concentration of boric acid in each treatment of the level low and the ridge height 15cm, and the degree of increase of each node order is remarkable in lower leaves and is more remarkable in the treatment of level low plot. The effects of leaf spray of boric acid are not only the increase of leaf area but also dry weight, no. of capsule per plant, 1,000 grains weight of capsule setting under middle position. As a result, the amount of seed is increased in 53% in the treatment of level low. The change of major characteristics according to leaf spray of boric acid is generally great in the treatment of level low. Especially the increase of leaf area in the part of upper leaves and low leaves is effective to improve other characteristics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.207-214
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• 1996

This study was conducted to obtain fundamental information on forage sorghum breeding in forage crop field of Livestock Experiment Station at Suwon from 1986 to 1991. The charcterization of sorghum germplasm was performed through 1986 to 1987, and after parental lines were selected from diverse sorghum germplasm on the basis of flowering date, plant height and several morphological characters for forage sorghum Fl hybrids. The range of variation of 50% flowering date and plant height were greater in order of forage sorghum sudangrass and male sterile line of grain sorghum. The average flowering date was earlier in sudangrass and male sterile line of grain sorghum than forage sorghum lines from the tested sorghum germplasms. And the average plant height was tall in order of forage sorghum, sudangrass and male sterile lines of grain sorghum. There were remarkable morphological variations between sudangrass lines and male sterile lines of grain sorghum such as plant color, leaf midrib color, glume color, seed coat color, head compactness and shape, awns, grain covering and 100 seed weight.

• Economic and Environmental Geology
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• v.42 no.6
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• pp.575-589
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• 2009

Groundwater has been extracted for irrigation in Sacheon-Hadong area, which is close to the South Sea. We analyzed chemical components of groundwater to examine the effects of seawater intrusion and agricultural activities in the study area. Most groundwater samples displayed the Na/Cl concentration ratios similar to that of seawater (0.55) with an increasing tendency of electrical conductivity ($227-7,910\;{\mu}S/cm$) towards the coast. In addition, statistical interpretation of the cumulative frequency curves of Cl and $HCO_3$ showed that 30.1% of the groundwater samples were highly affected by seawater intrusion. Groundwaters in the study area mostly belonged to the Ca-Cl and Na-Cl type, demonstrating that they were highly influenced by seawater intrusion and cation exchange. The result of oxygen-hydrogen isotope analysis demonstrated slightly higher $\delta^{18}O$ ((-8.53)-(-6.13)‰) and ${\delta}D$ ((-58.7)-(-43.7)‰) comparing to mean oxygen-hydrogen isotope ratios in Korea. As a result of nitrogen isotope analysis, the $\delta^{15}N-NO_3$ values ((-0.5)-(19.1)‰) indicate two major sources of nitrate pollution (organic nitrogen in soil and animal and human wastes) and mixed source of the two. However, denitrification may partly contribute as a source of nitrogen. According to factor analysis, four factors were identified among which factor 1 with an eigenvalue of 6.21 reflected the influence of seawater intrusion. Cluster analysis indicated the classification of groundwater into fresh, saline, and mixed ones.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.2
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• pp.135-141
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• 2012

Purpose: Polymerization of HEMA(2-hydroxyethyl methacrylate) which can be used in the soft contact lens has been performed by using electron beam(EB) irradiation, and examined the best condition for the polymerization. Comparing the physical properties of the contact lenses to the one fabricated by thermal polymerization method, we check the use possibility of the EB irradiation to the fabrication of the soft contact lens. Methods: We investigated the degree of polymerization of the HEMA according to the composition of the monomer, the additive ratio and the dose of electron beam (0~120 kGy). The degree of polymerization was measured depending on the EB dose to research the best synthetic condition under the EB irradiation. The physical properties of the contact lens such as water content(%), oxygen transmissibility(Dk/t) and optical transmittance were analysed by using the FT-IR results with comparing the two different polymerization method (thermal and electron beam polymerization) with same additive ratio. Results: When the dose of electron beam was above 100 kGy, the degree of polymerization of HEMA was above 99% with regardless using cross-linker and initiator. The water content of the lens fabricated by EB method showed 10% higher than the one by the thermal method which was 40%. The lens fabricated by EB method also showed higher oxygen transmissibility(Dk/t) as same with the water content, and showed twice higher value in the lens fabricated by pure HEMA. According to the FT-IR results, hydrophilic property of the lens fabricated by EB method was increased due to increasing the intermolecular hydrogen bonding. It showed above 90% optical transmittance in the visible range of wavelength on the contact lenses fabricated by the both of two different polymerization method. Conclusions: The polymerization of HEMA without cross-linker and initiator was successful above 100 kGy of EB irradiation. Moreover the lens fabricated from the polymer synthesized by pure HEMA with 100 kGy of EB showed the highest water content and oxygen transmissibility. Therefore EB irradiation is another possible method to synthesize the polymer which can be used for the soft contact lens.

• Journal of Nutrition and Health
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• v.14 no.2
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• pp.97-104
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• 1981

In order to study the changes of components and enzyme activities during Chungkookjang-Koji preparation, the Kojies were prepared with Bacillus Natto, Bacillus subtilis and traditional method. The temperature of Koji materials during Koji preparation was very different according to the experimental group. The content of ethyl alcohol, reducing sugar, amino nitrogen and water soluble nitrogen were changed by the Koji preparing stage and experimental group. Amylase and protease activities showed on irregular change on standing and their activities were not remarkably different among the groups and appeared weakly.