• The Journal of the Petrological Society of Korea
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• v.4 no.1
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• pp.49-58
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• 1995

Staurolite-biotite-andalusite-garnet (SBAG) assemblage and its sub-assemblages (SBA and SBG) commonly occur in the Dueumri Formation near the Chunyang granite, belonging to andalusite and sillimanite zones. The occurrence of the SBAG mineral assemblage is unusual because it is univariant in the $K_2O-FeO-MgO-Al_2O_3-SiO_2-H_2O$ (KFMASH) model system. We used projection and singular value decomposition (SVD) methods to investigate the equilibrium relationship between SBAG and its sub-assemblage. The SVD modelling of single specimen containing the SBAG assemblage suggests no reaction relationship with respect to mass-balance. Thus, the SBAG assemblages are stabilized by non-KFMASH component. On the other hand, the AFM-Mn projection suggests a reaction relationship between SBAG and its sub-assemblage because they intersect each other in this composition space. The SVD modelling, however, suggests no reaction relationship between these assemblages. Thus, the SBAG assemblages are likely to be stabilized by the variation in bulk-rock composition and/or 1.1~2,. The stable occurrence of staurolite in the sillimanite zone is compatible with pressure estimates from the garnet-plagioclase-biotite-muscovite geobarometer.

• Economic and Environmental Geology
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• v.14 no.4
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• pp.167-182
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• 1981

Skarn silicates from the Shinyemi lead-zinc ore deposits can be distinguished as following three mineral assemblages: 1) garnet-pyroxene-phlogopite-wollastonite assemblages, 2) garnet-pyroxene assemblages, 3) garnet-epidote assemblages The assemblages are considered to be related with occurrences and kindes of ore minerals, and stage of mineralization in the deposits. Microprobe analyses of some garnets from the deposits show strong chemical zoning which is due to the changing equilibrium condition during growth of garnet crystal. Depositional condition of ore deposits and place of the ore-related igneous rock are discussed in the light of chemical composition of garnet and occurence of skarns in the Shinyemi.

• Journal of the Mineralogical Society of Korea
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• v.28 no.3
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• pp.265-277
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• 2015

Hydrothermal alteration patterns and environment are studied by mineral assemblages and chemical analyses of surface and core samples from Miryang pyrophyllite deposit. The alteration zones of this deposit can be divided into three zones on the basis of mineral assemblage; advanced argillic, phyllic, and propylitic zone. Advanced argillic zone mainly consists of pyrophyllite-dickite (-quartz) and corresponds to principal mining ore. The common mineral assemblage of phyllic zone and propylitic zone are sericite-quartz-dickite and chlorite-quartz, respectively. Horizontal and vertical alteration patterns and major element geochemistry indicate that pyrophyllite ores have been formed several times by hydrothermal alteration. And it also suggests that the huge ore bodies may be extended from the deeper part of recent quarries to the south-southeastern direction. The paragenesis of ore minerals and polytype (2M) suggest that ore deposit was formed at about $300-350^{\circ}C$.

• Journal of the Mineralogical Society of Korea
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• v.13 no.4
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• pp.205-220
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• 2000

북동태평양 C-C지역의 우리나라 광구에서 산출되는 망간단괴의 내부조직을 크게 주상조직 층상대, 첨상조직 층상대, 첨상조직 괴상대, 첨상조직 다공질대 및 괴상조직 괴상대로 구분하였다. 주상조직 층상대에서는 버나다이트(vernadite)가 가장 우세하게 산출되며, 첨상조직 층상대에서는 부서라이크(buserite)가 함께 산출된다. 첨상조직 괴상대는 부서라이트의 산출이 두드러지며, 부분적으로 토도로카이트(todorokite)가 수반된다. 첨상조직 다공질대는 첨상체 또는 구상체로 이루어지며 부분적으로 괴상조직으로 교대되는데 주로 토도로카이트와 부서라이트로 구성되어 있다. 괴상조직을 갖는 괴상대에서는 토도로카이트와 버네사이트(birnessite)가 부서라이트와 함께 산출된다. 각 조직대별로 미세조직을 이루는 엽리들에 대해 전자현미분석을 실시하였다. 엽리의 화학조성을 구성하는 요인은 상관계수 군집분석에 의해 Mn-K의 Mn군, Cu-Ni-Zn-Mg(Ca-Na)의 Cu-Ni-Mg군 Fe-Co-Ti(Ca-P)의 Fe군과 Si-Al의 Si군 등 네 개군으로 구분된다. 각 조직대는 세 개 또는 네 개의 군으로 구성되며 이들 각군은 단괴에서 산출되는 광물과 밀접한 관계를 가진다. Mn군은 토도로카이트, Cu-Ni-Mg군은 부서라이트, Fe군은 함코발트수산화철광물, 그리고 Si군은 규산염광물에서 주로 기인하는 것으로 생각된다. 엽리의 화학조성은 이들 광물의 조합과 구성광물의 화학조성에 따라 지배되고 한 조직대내에서도 여러종류의 조합을 보이는데 이는 각 조직대의 엽리들의 성인과 밀접한 관련이 있는 것으로 생각된다.

• The Journal of the Petrological Society of Korea
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• v.7 no.3
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• pp.177-189
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• 1998

Proterozoic gneisss complex of the Paju-Gimpo area, Northwestern Gyeonggi Massif, consists of mainly gneiss and schist with locally intercalated quartzite and metamorphic calcareous rocks. Mineral assemblages of the gneiss and schist are classified into two type: sillimanite free (garnet zone) and sillimanite bearing (sillimanite zone) assemblages. In the Goyang area, Kyanite occurs as metastable relict grain in two gneiss samples, in which sillimanite, garnet, biotite, K-feldspar and plagioclase occur. Cordierite bearing mineral assemblages of gneiss are biotite+garnet+sillimanite+cordierite+plagioclase+quartz ($\pm$K-feldspar, muscovite), and represent the upper amphibolite or granulite facies metamorphism. The metamorphic complex has experienced two different regional metamorphism. The prograde metamorphism is a medium-pressure type characteries by kyanite. The peak metamorphic P-T condition of the prograde metamorphism calculated from the kyanite bearing rock is 7.0~9.4 kb and $718~778^{\circ}C$. The retrograde metamorphism, after the prograde metamorphism, is the low-pressure type characteries by occurrence of cordierite. The peak metamorphic P-T condition of later calculated from the cordierite bearing rock is 3.6~5.5 kb and $750~889^{\circ}C$. Together with the occurrence of relict kyanite, garnet+biotite+plagioclase assemblage as relict in the cordierite, and the result of estimated P-T metamorphic conditions indicate a clockwise P-T path.

• Journal of the Korean Ceramic Society
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• v.40 no.12
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• pp.1235-1240
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• 2003

The mixtures which are in the chemical composition of Portland cement were prepared from oyster shell, casting dust and BOF slag. The clinkerbility and the behaviour of formation of clinker minora]s were studied using the mixtures mainly by the mineral and microstructural observation. By virtue of the characteristics of starting raw materials, the clinkering temperature was lower as much as 100$^{\circ}C$ than that of a mixture prepared from normal raw materials. Uncombined calcium oxide was vanished entirely below 1350$^{\circ}C$. and the formation of major cement minerals such as alite and belite could be nearly accomplished without too much liquid phase within 1400$^{\circ}C$.

• Journal of the Mineralogical Society of Korea
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• v.22 no.2
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• pp.163-176
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• 2009

The pyrophyllite deposits located in Jinhae area have been studied through field observations and laboratory works including the X-ray diffraction (XRD), X-ray fluorescence (XRF), Electron probe microanalyzer (EPMA) and Inductively Coupled Plasma (ICP). The pyrophyllite deposits consist of mainly illite, dickite, pyrophyllite, diaspore, chlorite, pyrite and copiapite. According to the mineral assemblages, geological occurrences and alteration modes, the altered rocks can be classified into four types: Type A; quartz with silicifictaion, Type B; quartz + illite with illitization, Type C; quartz + dickite + illite with kaolin alteration, Type D; pyrophyllite + illite + dickite + diaspore with pyrophyllite alteraion. Rocks in Type A, which is generated by silicifictaion, have high $SiO_2$ contents more than 90 wt% and distinctive equigranular textures with microcrtstalline quartz. The pyrophyllites from the study area belong to 2M polytype. The host rocks of the pyrophyllite ore in this mine are rhyolitic rock, andecitic tuff and volcanic breccia. The alteration products seem to be controlled by the different lithology of the host rocks. The hydrothermal solution formed the deposits would be inferred to the acidic and have relatively high ionic activity of hydrogen and silica judging from alteration mineral assemblage. Pyrophyllite alteraion zone is generated by highest temperature condition of all alteration zone.

• Journal of the Mineralogical Society of Korea
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• v.7 no.2
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• pp.97-110
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• 1994

고사리광산의 도석에는 다량의 석영과 함께 녹니석/스멕타이트 혼합층광물, 운도/스멕타이트 혼합층광물, 카오리나이트와 같은 점토광물이 산출한다. 이들 점토광물에 대해 주로 X-선회전분석과 화학분석 등을 이용하여 광물학적 특성을 검토하였다. 이 광산의 도석은 녹니석/스멕타이트 혼합층광물을 다량 함유하는 것이 특징으로 나타났다. 이 녹니석/스멕타이트 혼합층광물은 Li을 함유하는 돈바싸이트로 된 녹니석층과 바이델라이트에 가까운 스apr타이트층으로 구성된 혼합층구조를 이룬다. 이 곳에 산출하는 운모/스멕타이트 혼합층광물은 모두 약 15% 이하의 팽윤층을 포함하는 것으로 되어 있다.이 광산의 도석은 백악기의 유문암 및 유문암질 응회암이 열수변질작용을 받아 형성된 것으로 나타났다. 점토광물조합의 분포상태에 의해 대략적인 변질분대가 나누어진다. 중심부인 강변질대에서는 다량의 녹니석/스텍타이트 혼합층광물이 나타나며 카오리나이트가 수받되기도 한다. 그 외곽지역의 약변질대에서는 점토광물로서 운모/스멕타이트 혼합층광물이 주로 나타난다. 카오리나이트는 주로 열극이나 그 주위에 국부적으로 산출되는 경향이 있다. 이와 같은 변질광물의 산출상태로 볼 때 변질작용의 진행에 따라 운모/스멕타이트 혼합층광물이 먼저 형성된 후 이것의 일부가 녹니석/스맥타이트 혼합층광물 및 카오리나이트로 변화된 것으로 생각된다. 도 카오리나이트는 열수의 공급이 많은 열극부에서 녹니석/스멕타이트 혼합층 광물과 거의 동시기에 침전된 것으로 생각된다. 이 광산에서 산출하는 일부 운모/스멕타이트 혼합층광물은 후기의 변질작용에 의해 형성된 것도 포함된다.

• The Journal of the Petrological Society of Korea
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• v.6 no.3
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• pp.226-243
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• 1997

The Odesan Gneiss Complex consists of mainly migmatitic gneiss and porphyroblastic gneiss with locally intercated quartzite, amphibolite, marble and leucocratic gneiss. At least two different regional metamorphisms are recognized in the study area. Metamorphic grade of the first metamorphism increases from the K-feldspar-muscovite zone(in which biotite-muscovite-plagioclase-quartz and garnet-biotite-muscovite-K-feldspar-plagioclase-quartz assemblages occur) in the east and southwestern part of the study area to the K-feldspar-garnet zone(in which garnet-biotite-K-feldspar-plagioclase-quartz, biotite-K-feldspar-plagioclase-quartz, garnet-biotite-K-feldspar-plagioclase-sillimanite-spinel-quartz assemblages occur) in the northwestern part. Kyanite is found as inclusions in plagioclase. The second metamorphism is characterised by occurrence of cordierite. The metamorphic grade of 2nd metamorphism decreases radically from the central-western part near Gaeinsan in which cordierite-garnet-sillimanite-biotite-muscovite-quartz, cordierite-garnet-spinel-sillimanite-biotite-muscovite-quartz assemblages representing the garnet-cordierite zone are observed. The garnet-cordierite zone is surrounded by the sillimanite-cordierite zone which shows cordierite-sillimanite-biotite-plagioclase, cordierite-muscovite-biotite-plagioclase and sillimanite-muscovite-biotite-plagioclase assemblages. The peak metamorphic P-T conditions of the first metamorphism calcuted from garnet-biotite-sillimanite-K-feldspar-plagioclase-spinel assemblage are 5.4~7.4 kb and $776-789^{\circ}C$. Real P-T condition of the first metamorphism might be higher than the calcuated P-T condition according to the study based on the phase equilibria. P-T conditions calcuated from the garnet-biotite in plagioclase are 12.5kb and $650^{\circ}C$ which indicate that the P-T path of the first metamorphism had passed a high pressure condition before the peak metamorphic temperature condition. The peak metamorphic P-T conditions of the second metamorphism calcuated from garnet-biotite-cordierite-spinel-quartz assemblage are $680~750^{\circ}C$ at pressures lower than 6 kb. In the Odesan Gneiss Complex, the first metamorphism of medium pressure and high temperature had occurred after the high pressure condition and fast uplift and then the second metamorphism of low pressure condition occurred after sedimentation of the Kuryong Group.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.1
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• pp.26-33
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• 2014

The study investigates the effects of the type, replacement ratio and method of use of mineral admixtures on the fluidity, bleeding ratio, volumetric change and compressive strength of the grout in order to provide basic data for the development of high-quality grout for PSC bridges. In view of the results relative to the type and replacement ratio of the mineral admixtures, it appears that fly ash has practically no effect on the improvement of the fluidity nor on the reduction of bleeding and shrinkage of the grout. On the contrary, blast furnace slag and silica fume appear to have significant effect on the improvement of the fluidity or on the reduction of bleeding and shrinkage of the grout. With regard to the combined use of mineral admixtures, the combination of fly ash and blast furnace slag provides satisfactory fluidity but with significant increase of bleeding and shrinkage, whereas the combination of blast furnace slag and silica fume reduces bleeding and shrinkage but with large loss of the fluidity. On the other hand, the combination of fly ash and silica fume results in satisfactory fluidity accompanied with fair reduction of bleeding and shrinkage of the grout. In view of these results, the type, replacement ratio and method of use of the mineral admixtures are seen to influence the fluidity, bleeding and volumetric change of the grout. Accordingly, it is necessary to select the mineral admixtures considering these effects for their exploitation in the grout of PSC bridges.