• Economic and Environmental Geology
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• v.10 no.2
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• pp.53-66
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• 1977

Epithermal Mn-Au-Ag deposits of subvolcanic type in the Yeongil area discovered by one (Soo Jin Kim) of the present authors was studied with emphasis on their mineralogy, genesis and future potential. Mineralization is genetically related to volcanic activities of the Tertiary Period, which have produced porphyritic rhyolite, granite porphyry, felsitic rhyolite and agglomerate. Ore deposits are closely associated with felsitic rhyolite. They occur as breccia-filling, veins, or networks. Mineralization is characterized by rhodochrosite-sulfide ores of breccia-type in the central zone, and sulfide ores of disseminated type in the outer zone. Sulfides consist mainly of pyrite and marcasite, with minor chalcopyrite, sphalerite, argentian tetrahedrite, galena and gold in the central zone, and of pyrite, marcasite and argentian tetrahedrite in the outer zone. Sulfides are generally not easily identified with naked eye because of their very fine-grained nature. Wall rock alteration zones are also developed around ore deposits over the large area. Occurrence of ore deposits and the nature of mineralization indicate that the uppermost portion of ore deposits are now exposed on the surface, and therefore, the main mineralized zones are expected in depth.

• Economic and Environmental Geology
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• v.49 no.3
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• pp.193-199
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• 2016

Constancia mine is a deposit developed within Andahuaylas-Yauri Cu-Mo-Au metallogenic belt, southeastern Peru and is located in the southwestern part of Abancay deformation zone structurally as the porphyry copper deposit type. Mineralized zone in Constancia mine are composed of leached zone, secondary enrichment zone(ca. 1% Cu), mixed zone, primary mineralized zone(ca. 0.5%), skarn zone(ca. 1.5% Cu) from the upper part. Main country rock is monzonitic porphyry. Leached zone are characterized by the precipitation of limonite and looks brown in the outcrop. Oxidized zone have green due to the occurrence of copper oxide and secondary enrichment zone are characterized by the occurrence of chalcocite. Skarn zone are characterized by the occurrence of magnetite and garnet. Now, Hudbay, Canadian mining company, have 100% share about Constancia mine and started to produce commercially from January, 2015.

• Journal of the Mineralogical Society of Korea
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• v.16 no.3
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• pp.265-280
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• 2003

The Mugeuk mineralized area that associated with the pull-apart type Cretaceous Eumseong basin is composed of several gold-silver vein deposits that are emplaced in late Cretaceous biotite granite. The gold-silver deposits in the area show various hydrothermal alteration zones as well as Au/Ag ratios and ore mineralogy. The Geumbong mine showing relatively high gold fineness is composed of multiple veins and show alteration pattern; vein \longrightarrow phyllic \longrightarrow subphyllic \longrightarrow propylitic \longrightarrow subpropylitic zone. In contrast, The Taegeuk mines show the low fineness values, in far southern part are characterized by increasing tendency of simple and/or stockwork veins. The deposit displays alteration pattern; vein \longrightarrow propylitic \longrightarrow subpropylitic zone. Variations of alteration zone with depth show that phyllic zone are dominant in deeper level and propylitic zone sporadically overlapped by argillic zone are dominant in shallow level. The differences of alteration pattern between the gold-silver deposits are reflect the evolution of the hydrothermal fluids; the ore-forming fluids of the Geumbong mine are at relatively high temperature and salinity and highly-evolved meteoric water, developing phyllic zone, the Taegeuk mine containing greater amounts of less-evolved meteoric waters shows relatively low temperature and salinity in ore-forming fluids, developing propylitic zone. The various physicochemical environment for gold-silver mineralization in the Mugeuk mineralized area is due to proximity from heat source area (Mugeuk mine) to marginal area (Taegeuk mine) in a geothermal field. Therefore, it is suggested that the criteria for project exploration in the area are to focus on the area proximal to heat source and phyllic zone.

• Applied Microscopy
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• v.24 no.1
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• pp.59-76
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• 1994

Fine structure of the distal femoral epiphysis of growing mouse was studied by electron microscopy. The first morphological evidence of developing secondary center of ossification in the distal femoral epiphysis was found at newborn mouse. Ossification center was in the form of multiple foci of calcification and its cells were represented by remnant of degenerated cells within large lacunae that were separated by mineralized cartilaginous septa. Endochondral ossification beneath the articular cartilage proceeded in a less orderly manner than metaphyseal endochondral ossification. Columns of hypertrophied chondrocytes were not distinctly parallel to intercellular mineralized septa in all direction. Hypertrophied chondrocytes in the inner zone of the epiphseal center of ossification showed disintegrated. Resorption of mineralized cartilaginous septa was undertaken by perivascular cells and multinucleated chondroclasts. Resorption of the calcified cartilage was restricted to the region of ruffled border of the chondroclast. Growth along the metaphyseal side of the epiphyseal center of ossification was different from that along the articular surface. As the secondary center expanded toward the metaphyseal side, many vascular buds penetrated unmineralized cartilaginous septa and invaded viable chondrocytes. Many hypertrophied chondrocytes bodering the metaphyseal side of bone center remained viable after they became embedded in mineralized cartilaginous septa. This result suggested that the hypertrophied.

• Economic and Environmental Geology
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• v.4 no.2
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• pp.77-90
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• 1971

About four hundred deposits of iron, talc, fluorite, tungsten, molybdenum, lead, zinc and other polymetallic mineral deposits were plotted on the Ore Distribution Map of the Ockcheon Geosynclinal Area. These mineral deposits plotted on the map can be divided into the several metallogenic zones by the consideration of their geologic background including the sedimentary and tectonic cycles and the igneous activities in the geosynclinal evolution, as follows: a. Chungju iron and talc zones. b. Cheong-san copper bearing iron sulphide zone c. Kumsan-Muju fluorite-polymetallic zones. d. Cheong-an Puyong and Ein Suckseong gold zone e. Hwang-gan Seolcheon and Sangju gold zones. Chungju iron zone originated in the iron bed in the Kemyongsan Series corresponding to the Pre-Ockcheon Cycle of evolution history. In early period of the Ockcheon Cycle, Hyangsanri quartzite and Munjuri phyllitic formation corresponding to the lower terrigenous sequence were not mineralized while the next sequence of the Samsungsan basic igneous-metamorphic formation and the Changri limestone formation were mineralized by the copper bearing iron sulphide and the fluorite-polymetallic deposits respectively. Two generations of the gold zones are recognized. The earlier generation distributes directionaly in the outside of the Ockcheon sedimentary belt was followed by the earlier grantitic invasion of Jurasic in age, while the later generation scatters at random which was related to the nondirectional Cretaceous granitic intrusion of the Post-Ockcheon Cycle. Conclusively speaking, it was disclosed that the endogenic mineralization in the Ockcheon geosyn clinal zone was not conspicuous in its inner sedimentary belt except its limestone area but in its outer peripheral granitic or gneissic zones, and the related igneous activities occured in the Post-Ockcheon Cycle of evolution history.

• Economic and Environmental Geology
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• v.39 no.3 s.178
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• pp.343-351
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• 2006

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.99-115
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• 2008

• Economic and Environmental Geology
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• v.41 no.3
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• pp.373-382
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• 2008

• Economic and Environmental Geology
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• v.44 no.6
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• pp.565-572
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• 2011

• Economic and Environmental Geology
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• v.43 no.6
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• pp.661-670
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• 2010