• Economic and Environmental Geology
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• v.26 no.1
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• pp.83-96
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• 1993

Kwangju granite body located in vicinity of Kwangju city consist of three rock bodies-Kwangju rock body, Jangsung rock body and Youngkwang rock body. Petrochemistry of Kwangju granite is as follows: Kwangju granite body is igneous complex which compose of a series of differential products of a magma. Kwangju granites are divided into four rock facies based on the geologic age, mineralogical and chemical constituents and texture: Triassic hornblende-biotite granodiorite and biotite granite, and Jurassic porphyritic granite and two mica granite. Harker and other variation diagrams of Kwangju granites plot on trend of calc-alkali rock series and range of peraluminous granite. Parental magma type of Kwangju granites correspond to I-type, Syn-Collision type in compressive stress field by collision movement between both rock block. In chondrite normalized REE patterns of Kwangju grnites, LREE enriched than HREE in REE amount and have more steep negative slope with slightly (-) Eu anormaly.

• Economic and Environmental Geology
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• v.12 no.4
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• pp.197-206
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• 1979

Sangdong scheelite deposit is confirmed to have been formed by replacement of limestone beds by metasomatic mineralization. Mineralogical zonal distribution and filling temperatures are related with order of its formation and tungsten mineralization. The first formed garnet-pyroxene zone, left in the margins of the ore body, shows the highest filling temperature of fluid inclusions in pyroxene, averaging $420^{\circ}C$. The central part of the ore body, mainly composed of quartz-mica-scheelite, shows higher fi11ing temperatures of fluid inclusions in quartz, than hornblende-quartz-scheelite zone surrounding the quartz-mica-scheelite zone, averaging $240^{\circ}C$. The distribution of highter filling temperatures above average temperature is applicable to the richest part of scheelite distribution. Generally scheelite shows higher filling temperature by about 20 to $100^{\circ}C$ than quartz in a given sample. The crystallization temperature of the main phase of scheelite deposition is $311^{\circ}C$ at the pressure of 230 to 500 bars at Sangdong area. Gas-rich inclusions in the pyroxene are homogenized into either gas or liquid phase or into both phases in a given crystal of the pyroxene, which suggests boiling at the formation of skarn.

• Ocean and Polar Research
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• v.28 no.2
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• pp.187-199
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• 2006

The Kuroko-type seafloor massive sulfide deposits found in the western Pacific have been considered to have potentials for economic recovery of Au, Ag, Cu, Zn, and Pb. In this study, a preliminary model was developed for the technical and economic evaluation of them. The FRSC site on Lau Basin in the Tonga EEZ was selected as a target. In this study, no construction In for the metallurgical processing subsystem was accounted for. Instead, it was assumed to sell the Cu, Zn, and Pb concentrates to the existing sulfide customer smelter. The low total investment costs for the development make the venture very attractive. However, the result of the economic feasibility evaluation is still less attractive with the mean metal yield of the Kuroko on land. It is considered that commercial mining may be plausible if the richer metal yields are applied to the development. Quantitative information for metal yield is necessary for a more accurate evaluation. However, the important resource potential information regarding the amount of ore body, the inside structure, and the metal yields have not yet been clarified sufficiently. h addition, the flotation of ore body using seawater has not been tested yet. It is necessary to solve these problems through the experimental R&D and a survey.

• The International Journal of Costume Culture
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• v.2 no.1
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• pp.21-30
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• 1999

The purpose of this study was to examine differences in body image and attitudes and behaviors regarding cosmetic surgery between Korean and Americans. Forty females in the U.S and 40 in Korea participated in the study by being interviewed. As a result, while Koreans had positive attitudes toward cosmetic surgery, Americans had negative attitudes. Higher incidences of cosmetic surgery were found among Koreans than among Americans. Koreans with lower body image tended to have ore tolerance toward cometic surgery. These results suggest that cosmetic surgery might be one of many ways to improve their self-esteem, Korean women with lower body image showed higher attitudes or behaviors toward cosmetic surgery than Americans.

• Economic and Environmental Geology
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• v.19 no.spc
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• pp.113-119
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• 1986

A characteristic mineralogical zonal distribuion is observed in a large scale(whole ore- body) small scales(handy specimens). They show similar chemical variations: most of elements except CaO were supplied by hydrothermal fluids to form skarns. Garnets occuring in the pyroxene-garnet skarn have a wide range of chemical composition ranging from andradite to grossularite, while individual grains of the garnets also show a similar zonation of chemical composition varied between grossularite and andradite. Highly contained Mo-bearing scheelites are generally concentrated in the central part of the Sang- dong skarn orebody. Similarly, some large grains of scheelite show a nice zonation due to different contents of Mo, highly enriched in the core of the scheelite crystal. This geochemical similarity in the large scale and small scales suggests the Sangdong skarn formation was achieved under a certain chemical environment, and detailed studies on a small scale texture could be a clue to understand a whole ore deposit.

• Geophysics and Geophysical Exploration
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• v.17 no.4
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• pp.202-208
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• 2014

KIGAM (Korea Institute of Geoscience and Mineral Resources) and MRAM (Mineral Resources Authority of Mongolia) performed joint survey on Bayan-Onjuul W-Mo mineralized area. Following the survey, we carried out magnetic survey. W-Mo occurrences are located with keeping a certain distance from the northern boundary of granite which has higher magnetic susceptibility values. Also, the 3D imaging results of magnetic inversion show that granite bodies are extended to the W-Mo occurrence areas from the deep main body with decreasing of susceptibility. The results of magnetic data analysis are well matched with the general characteristics of ore solution involved with W mineralization. The further study about the hidden ore deposits which have similar spatial relationship between granite and known WMo occurrences are necessary to improve the economic feasibility.

• Economic and Environmental Geology
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• v.21 no.3
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• pp.235-255
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• 1988

Talc deposit of pipe-like form occurrs in the lower part of the Hyangsanri Dolomite with a strike of N40 -50 E and a dip of 40 -50 NW which is one formation of the Ogcheon Super Croup. The pipi-like ore body plunge at about $40^{\circ}$ to the west and are parallel to the lineation developed in the area. Structural formulae of tales occurred in this deposit are close to the ieal composition $Mg_6Si_8O_{20}(OH)_4$ showing limited deviation from ideal one. Substitution of Al for Si in tetrahedral site is of little or nothing ranging 0-0.04 and octahedral occupancy is close to six ranging 5.88-5.98 atoms per unit cell. Predominant octahedaral cation is Mg and proportion of divalent cations is generally over 97percent. Calcite -dolomite thermometry is obtained by determining the mol % $MgCO_3$using of EPMA and XRD methods. The peak metamorphic temperature can be estimated at $470{\pm}30^{\circ}C$ in the area whereas carbonates occurred at near talc ore show lower temperature than $400^{\circ}C$ that the calcite solvus limit is not well established. It indicates that the talc deposit was formed at the lower temperature that the metamorphic temperature. Cosequently, the formation of talc by metamorphism is questionable and the alteratin zone developed around the talc ore is very limited. The occurrence of talc ore in the dolomite as well as mineralogy, calcite-dolomite geothermometry, chlorite geothermometry, field and microscopic evidence suggest that siliceous ascending hydrothermal solution along the fracture is responsible for the formation of talc. It was considered that the slight fracturing of dolomite was formed by deformation prior to the mineralization.

• Economic and Environmental Geology
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• v.18 no.2
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• pp.93-105
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• 1985

Whether a skarn deposit in carbonate host occurs in contact with certain igneous mass or not has been a general criterion in identifying the igneous rock that genetically relates to the skarn deposit. It is well known, however, that there are many skarn deposits which are not close to any given igneous contact but are far away from the contact. In this paper the reason why such deposits can be formed at a distance from the contact as mentioned is expressed based on the concept that skarn deposits and related igneous rocks are genetically connected at depth where ore-forming fluids emanate from magma and are removed upwards; the movement of ore-forming fluids separated from magma at any depth may have a tendency to infiltrate upward in bulk rather than to diffuse laterally; the paths of magma and cogenetic ore-forming fluids may be identical at lower depths but the latter can be diverted from the former with upward movement so that the positions of the skarn deposits which resulted from the ore-forming fludis at upper levels can be distant from the igneous contacts on a given horizontal section. Statistics indicate that the majority of exoskarns are found at distances up to 800 meters or rarely up to 3,000 meters from igneous contacts and endoskarns up to 600 meters or more. Numerous case studies of skarn deposits in various parts of the world support the above reasoning indicating a general downward convergency of skarn orebodies and related igneous masses with depth. A typical example of this situation is well demonstrated at the Keumseong molybdenum deposit, which is apart from the Jecheon granite on the surface but gets closer to the granite body with depth and finally is intertongued with the granite apophyses in its root zone. Another case for skarn deposit not associated with igneous contact either laterally or vertically but with a deep-seated distal igneous mass is the Sangdong scheelite deposit; 700 meters below the scheelite orebody a blind pluton of muscovite granite, which intruded into the Precambrian crystalline schist, has been recently discovered by deep drilling.

• The Journal of the Petrological Society of Korea
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• v.19 no.1
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• pp.31-49
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• 2010

Nearly NS-trending Fe-Ti ore bodies intermittently occur in the Hadong anorthosites, south Korea, irrespective of the rock types of the anorthosites. In order to determine their occurrence mode and deformation history, we collected the features of occurrence and geological structures in the field, petrographic features using thin sections of the principal constituent rocks, and geochemical data of ilmenites in the ore body using electron probe microanalysis. Fe-Ti ore bodies examined in this study are divided into two types: dike- and lamina-types. It is steadily supported that the dike-type has intruded into the anorthositic rocks after their emplacement and solidification. And the laminar-type is probably a result of the mylonitization and transposition of the dike-type ore bodies parallel to the shear planes, due to later strong dextral ductile shearing. In the meantime, the Fe-Ti ore bodies have experienced the stronger dextral shearing in the more northern part of the study area, i.e. Cheongryong-ri, Wolhoeng-ri, Jonghwa-ri, and Jayangri and Baekun-ri in ascending order of its strength, together with the less content of $TiO_2$. All ilmenites of the ore bodies have very similar chemical composition, as pure ilmenite of 52~55 wt.% in $TiO_2$ content, irrespective of the occurrence mode and degree of later ductile shearing of the ore bodies. And they didn't experience to exsolve into magnetite. The structural data indicate that the Hadong anorthosites have deformed by NNE-trending folding, intrusion of the Fe-Ti ore bodies, NNW~NNE-trending dextral ductile shearing, NW~NNW-trending sinistral semi-brittle shearing, and intrusion of NNE~NE-trending mafic dykes in descending order of chronology after the formation of foliation of the anorthositic rocks. The foliation is interpreted as a result of the accumulation of crystals that settle out from the magma by the action of gravity.

• Tunnel and Underground Space
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• v.27 no.3
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• pp.161-171
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• 2017

Demand for high-grade limestone is increasing, but the production in the domestic mines has been limited due to the lack of systematic development plans and efforts to develop mining technology to improve the recovery ratio, transition to high-cost underground mining due to increasing social awareness of environmental protection, and the smallness of the domestic mining industry, etc. In this study in connection with this issue, an analysis on the recovery change by improvement of mining method was executed. 3D modeling technique was used to construct a 3D model. 3D model includes the geological structure, the limestone ore body and the underground pits and tunnels excavated at the Daepyeong District of Daesung MDI Donghae District. By using the 3D model, measured resources, reserves and ore recovery were evaluated from the results of pilot operation of the room and pillar hybrid mining method, which is a variant of room and pillar mining method. These results were compared with those obtained from the conventional mining method. The ore recovery obtained by hybrid mining method was found to be up to 71.6%, showing about 26%p. increase compared with the case of conventional mining method.