• The Journal of the Petrological Society of Korea
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• v.5 no.1
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• pp.1-9
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• 1996

Eonyang amethyst deposits are thought to be spatially and temporally associated with the biotite granite of the Kyeongsang Basin. The examined euhedral quartz crystals in cavities in the aplite intruded biotite granite are colored-zoned from white at the base to amethystine at the tops. Three types of primary Inclusions were observed and three is representing each types are constructed to constrain the trapping conditions and fluid evolution involved during the formation of the amethyst. The intersection of the isochore representing the early fluid inclusions with solidus temperature of the host granite indicates initial quartz formation at about $600^{\circ}C$ and 1.0-1.5 kbars . Intermediate quartz formation, associated with the high-salinity inclusions, occurred at somewhat lower temperatures ($400^{circ}c$) and pressures of about 1 kbar. The amethystine quartz formed from $H_2O$-$CO_2$-NaCl fluids at temperatures between 280-$400^{circ}c$ and pressures of about 1 kbar. Early quartz is interpreted to have formed from fluids that either exsolved from or were in equilibrium with the granite at near solidus conditions, whereas the amethystine quartz apparently grew from fluids of at least partial sedimentary origin.

• Journal of Korea Foundry Society
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• v.29 no.6
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• pp.270-276
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• 2009

After casting button-type small ingots of ternary Fe-Mn-S alloys which had three different Mn/S ratios (1, 5 and 70) in a vacuum arc furnace, the effect of the ratio on the sulfide formation was investigated. In case of the Mn/S ratio of 1, if alloy composition was located in an iron-rich corner on a Fe-Mn-S ternary phase diagram, only duplex MnS-FeS sulfide films were observed in the grain boundary. If the alloy composition was located in the miscibility gap area of the phase diagram, primary globular dendritic sulfides and dendritic sulfide slags were generated within the grain and tubular monotectic sulfides were also detected in the grain boundary. When the Mn/S ratio was 5, if the alloy composition was in the iron-rich corner, only bead-like sulfides were generated. On the other hand, if the composition was in the miscibility gap area, globular dendritic sulfides and dendritic sulfide slags were generated in the form of primary sulfide inclusions and rod-like eutectic sulfides were observed in the grain boundary. Especially, if the contents of Mn and S increased more in the miscibility gap area of the phase diagram, primary globular sulfides containing iron intrusions were observed. In case of Mn/S ratio of 70, if the contents of Mn and S was decreased in the Fe corner of the phase diagram, only bead-like sulfides were observed in the grain boundary. Despite the composition was outside the miscibility gap area of the phase diagram, if the contents of Mn and S increased, clusters of fine sulfide particles as well as fine spherical primary monophase sulfides were observed in the grain boundary.

• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.3
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• pp.221-230
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• 2000

The usefulness and limitations of the impact-resonance method, which is a nondestructive evaluation (NDE) method for concrete, are studied by both experimental and theoretical methods. For the experimental study, several concrete slab specimens with various inclusions embedded were fabricated, and tested by the impact-resonance method. Some of the inclusions have been detected and accurately located, but some have not. The reasons for the failure in the latter cases have been investigated theoretically by using finite element analyses, from which the primary factors determining the success of the method have also been identified. This study will serve to enhance the understanding of the underlying physics and to improve the usefulness of the impact-resonance method as applied to concrete NDE.

• Economic and Environmental Geology
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• v.2 no.4
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• pp.1-21
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• 1969

The Sin po fluorite deposit is of a fissure vein type which strikes $N75^{\circ}E$, dips $80^{\circ}SE$, and is embedded in the pre-Cambrian crystalline schist. The vein is 1 meter in average in thickness, about 800 meters in length and nearly 400 meters in depth. Narrow veins of crustified fluorites and agatic quartz are discontinuously embedded in the quartz gangue. Two-phase fluid inclusions, which are available for the homogenization method by using the Heating Stage Microscope 350, are found in the fluorite crystals. Most of the fluid inclusions are primary in origin and mainly composed of liquid phase associated with minor gas phase. They are tetrahedral, rounded-tubular, wedge shaped, rectangulartrapezoid, and irregular in shape. The maximum diameter of inclusions is 0.5mm and the minimum, 0.03mm, ranging from 0.2mm to 0.08mm in an average. The homogenization temperatures obtained from the test are $135-147^{\circ}C$, $125-138^{\circ}C$, $121-137^{\circ}C$, $116-133^{\circ}C$ and $106-128^{\circ}C$ in greenish, bluish, violet, light grayish blue, colorless and pinkish fluorites respectively. The range of formation temperatures of fluorites is $106-147^{\circ}C$. Therefore, the fluorite deposit of Sinpo Mine is considered to be of low temperature hydrothermal origin. The isothermal lines were drawn on the longitudinal section of the vein from the data of homogenization test. According to the results, the central and lower parts of the ore shoot in the west ore body show the higher temperatures of $130-138^{\circ}C$ and the peripheral and upper parts of it show the lower temperatures of $108-128^{\circ}C$. It seems that the isothermal trend roughly coinside with the pitch of the ore shoot.

• Economic and Environmental Geology
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• v.15 no.4
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• pp.221-233
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• 1982

Ssangjeon tungsten ore deposits is a complex pegmatite deposits embedded along the contact between pre-Cambrian Buncheon granite gneiss and amphibolite. This pegmatite vein developed 2 km along the strike and thickness varies from 10m to 40m. Mineral constituent of the normal pegmatite are quartz, microcline, plagioclase, muscovite, biotite, tourmaline and garnet. The vein paragenesis is complicated by repeated deposition of quartz but three distinct depositional stage can be recognized. Quartz A stage is the stage of the earliest milky white quartz deposition as a rock forming mineral of normal pegmatite. Quartz B stage is the stage of gray to dark gray quartz replace earlier formed normal pegmatite minerals. Quartz C stage is the stage of latest white translucent massive quartz replace quartz A and B. Tungsten ore minerals and other sulfide minerals were precipitated during quartz B stage. Ore minerals are ferberite and scheelite. Minor amount of molybdenite, arsenopyrite, pyrrhotite, pyrite, chalcopyrite, sphalerite, galena, pentlandite, bismuthinite, native bismuth and marcasite accompanied. Fluid inclusion in quartz A and B are gaseous inclusions and liquid inclusions are contained in quartz C as a primary inclusions. Salinity of inclusions in quartz A and B ranges from 4.5 to 9.5 wt. % and from 5.1 to 6.0 wt. % equivalent NaCl respectively. Homogenization temperature of quartz A; quartz B and quartz C ranges from 415 to $465^{\circ}C$, from 397 to $441^{\circ}C$ and from 278 to $357^{\circ}C$. $CO_2$ content of the ore fluid increased at the ends of quartz B stage.

• The Journal of the Petrological Society of Korea
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• v.18 no.4
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• pp.337-348
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• 2009

Clear and homogeneous glass inclusions are well preserved at the rim of the quartz phenocrysts of tuff from Sunshin epithermal Au deposit, Haenam, although the host rocks experienced extensive silicification and argillic alteration. Glass inclusion vary in size from $5\;{\mu}m$ to larger than $200\;{\mu}m$ consisting of glass(60~80 vol%) + vapor bubble(15~30 vol%) $\pm$ daughter crystals(<10 vol%). Most of glass inclusions are cubic to rectangular in shape, indicating that the host quartz grew in the stability field of $\beta$-quartz. All the glass inclusions appear to be primary. Glass inclusions are composed of highly evolved high-K calc-alkaline rhyolites, which can represent the final liquidus phase of the magma system. The $Au_2O_3$ concentration (<0.30 wt%) is trivial in the glass, indicating there was no enrichment in the final residual melt. Textural characteristics suggest that magma was water-saturated shortly before or during the eruption. $H_2O$ content of the glass (ca. 2-4 wt%) suggests a water saturation pressure($P_{H2O}$) of about 300-900 bars. This pressure implies a minimum depth of 0.8-2.5 km for the magma chamber.

• Economic and Environmental Geology
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• v.46 no.1
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• pp.11-19
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• 2013

The Daehwa Mo-W deposit is located within the Gyeonggi massif. Quartz and calcite vein mineralization occurred in the Precambrian gneiss and Jurassic granites. Three main types (Type I: liquid-rich $H_2O$ type, Type II: vapor-rich $H_2O$ type, Type III: $CO_2-H_2O$ type) of fluid inclusions were observed and are classified herein based on their phase relations at room temperature. Within ore shoots, type III fluid inclusions have been classified into four subtypes (type IIIa, IIIb, IIIc and IIId) based on their volume percent of aqueous and carbonaceous ($CO_2$) phase at room temperatures combined with their total homogenization behavior and homogenization behavior of $CO_2$ phase. Homogenization temperatures of primary type I fluid inclusions in the quartz range from $374^{\circ}C$ to $161^{\circ}C$ with salinities between 13.6 and 0.5 equiv. wt.% NaCl. Homogenization temperatures of primary type III fluid inclusions in quartz of main generation, are in the range of $303^{\circ}C$ to $251^{\circ}C$. Clathrate melting temperatures of the type III fluid inclusions were 7.3 to $9.5^{\circ}C$, corresponding to salinities of 5.2 to 1.0 equiv. wt. % NaCl. Melting and homogenization temperatures of $CO_2$ phase of type III fluid inclusions were -57.4 to $-56.6^{\circ}C$ and 29.0 to $30.8^{\circ}C$, respectively. Fluid inclusion data indicate a complex geochemical evolution of hydrothermal fluids. The Daehwa early hydrothermal system is characterized by $H_2O-CO_2$-NaCl fluid at about $400^{\circ}C$. The main mineralization occurred by $CO_2$ immiscibility at temperatures of about 300 to $250^{\circ}C$. At the late base-metal mineralization aqueous fluid formed by mixing with cooler and less saline meteoric groundwater.

• Korean Journal of Materials Research
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• v.9 no.2
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• pp.217-225
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• 1999

The effect on the pitting corrosion resistance of laser welding and surface treatment developed as a repair method of stream generator tubing material that was a major component of primary system at nuclear power plant was observed. Some heat-treated Alloy 600 tubing materials used at domestic nuclear power plants were laser-surface observed. Some heat-treated Alloy 600 tubing materials used at domestic nuclear power plants were laser-surface melted and the microstructural characteristics were examined. The pitting corrosion resistance was examined through Ep(pitting potential) and degree of pit generation by means of the electrochemical tests and the immersion tests respectively. The pit formation characteristics were investigated through microstructural changes and the pit initiation site and pit morphology. The test results showed that the pitting corrosion resistances was increased in the order of the followings; sensitized Alloy 600, solution annealed alloy600, and laser surface melted Alloy 600. Pits were initiated preferably at Ti-containing inclusions and their surroundings in all tested specimens and it is believed that higher pitting resistance of laser-surface treated Alloy 600 was caused by fine, homogeneous distribution of non-soluble inclusions, the disappearance of grain boundary, and the formation of dense, stable oxide film. The major element of corrosion products filled in the pit was Cr. On the other hand, Fe was enriched in the deposit formed on the pit.

• Journal of Korea Foundry Society
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• v.29 no.5
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• pp.220-224
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• 2009

In order to investigate the microstructural morphology of the sulfide expected from the Fe-FeS phase diagram, a vacuum-sealed quartz tube where pure iron (99.9%) and sulfur (99.99%) powders were charged was heated upto $1000^{\circ}C$ in the electric resistance furnace, held for 96 hours and quenched in cold water and then, rod specimen was produced. Compositional difference of the sulfur between upper and lower parts of the rod was 7.5wt.% and segregation of the sulfur was gradually increased from the lower part to the upper one of the rod. The rod specimen was divided into three parts by the microstructural morphology of the sulfide. The upper part of the rod specimen revealed single phase FeS intermetallic. In the middle part of the specimen, hyper-eutectic microstructure where primary FeS was precipitated first and then, eutectic of $\alpha$-Fe and FeS was formed in the inter-dendritic region of the FeS. Especially, hypo-eutectic microstructure was appeared in the lower part of the specimen. After primary dendrite of $\alpha$-Fe solidified, FeS dendrite which included small amount of $\alpha$-Fe and FeS eutectic in the inter-dendritic region was formed.

• The Korean Journal of Cytopathology
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• v.4 no.1
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• pp.41-44
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• 1993

A case of primary amelanotic melanoma of the vagina diagnosed in scraping smear is described. A 64-year-old woman complained of vaginal bleeding with a $2.5\times2cm$ sized, fungating mass on the right lateral vaginal wall near the introitus for 2 months. Scraping smears from the mass showed scattered individual tumor cells with single, bi- or multi-nucleated eccentric nuclei having prominent macrouucleoli and occasional intranuclear inclusions. The cytoplasm was plump and cyanophilic with a indistinct rim. No melanin pigment was identified. Characteristic cytologic features of this case were very helpful to exclude more common squamous cell carcinoma in the vagina, which was strongly suggested in biopsy specimen.