• Journal of Forest and Environmental Science
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• v.36 no.3
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• pp.187-198
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• 2020

This study extracted deforestation area and degraded forestland area, which are potential REDD+ (Reducing Emissions from Deforestation and Forest Degradation) project candidate areas in Paraguay using Land Cover Map (LCM) and Tree Cover Map (TCM). The REDD+ project objectives scenarios were set three stages: 'afforestation and economic efficiency scenario', 'local capacity reinforcement scenario', and 'Infrastructure-oriented scenario'. And then, we evaluated the project unit suitable area of the REDD+ project. All scenarios selected the evaluation factors for each scenario in addition to the area ratio factors for deforestation area and degraded forestland area and weighted values were extracted by assigning category scores. As a result of the three scenarios comparison analysis, Concepcion state score was the highest. Within Concepcion state, the Belon district had the highest score, making it appropriate as a project unit REDD+ project candidate area in Paraguay, while the San Carlos district had the lowest score. This study can be used as basic data for selecting REDD+ project candidate area in Paraguay, and it is expected to contribute sufficiently to REDD+ project if additional data or information of social, cultural and economic sectors are secured.

• Journal of Digital Contents Society
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• v.13 no.3
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• pp.301-307
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• 2012

This study deals with the influencing factors for satisfaction of mobile coupon service. Thus researcher examined a structural equation modeling methodology of the path within word of mouth, satisfaction, and other exogenous variables (economic value, trust, joyfulness, innovativeness). As a result of this study, mobile coupon users understand the characteristics of basic coupon concept, and First, it was confirmed that the economic value, innovativeness affected user's trust for coupon service and joyfulness for using coupon. Second, it was confirmed that trust and joyfulness affected user's satisfaction and word of mouth activities. Moreover, this paper's contribution point is the proposes of the one of the post adoption model with the quantitative study of the industrial development stages of current various mobile coupon application.

• Economic and Environmental Geology
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• v.20 no.1
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• pp.61-75
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• 1987

The Daejang mine is one of the representatives of Cu-Pb-Zn-(Ag) vein deposit related genetically to late Cretaceous granitoid in Korea. Sericite from an alteration halo of the mine yielded a K-Ar date of $95{\pm}3.5Ma$. Based on macrostructures of vein filling, three major mineralization stages (I, II and III) are distinguished by tectonic breaks. Major ore constituents are arsenopyrite, pyrite, pyrrhotite, sphalerite, chalcopyrite, galena, boulangerite, with small amounts of Ag-bearing tetrahedrite, pyrargyrite, native bismuth, marcasite, siderite, ankerite, gudmundite and calcite. Characteristic feature of each mineralization stage and compositional variation of sphalerite and arsenopyrite are discussed in relation to the genetic environments. The FeS contents of sphalerites are 20.5~14.9 mole % in stage I, 17.9~11.9 mole % in stage IIA, 17.0~9.2 mole % in stage IIB, and 6.9~4.7 mole % in stage III. Their results are indicative of decreasing FeS contents during mineralization process in sphalerite coexisting with sulfur-rich sulfide assemblages, such as monoclinic pyrrhotite and pyrite, and is agreement with the conclusions shown by Scott and Kissin(1973). The composition of arsenopyrite decrease also in As content from stage I to stage III, and the compositional variation correlate with position of the associated minerals in the paragenesis. Temperature and pressure of the mineralization are determined as $250{\sim}430^{\circ}C$ and 4.0~0.3kb respectively, based on the chemistry of the minerals.

• Economic and Environmental Geology
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• v.21 no.1
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• pp.17-27
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• 1988

The Cretaceous Jinsan gold-bearing hydrothermal veins occur within the Late Proterozoic to Mid Ordovician metasedimentary rocks, intruded by Early Cretaceous pink-feldspar granite($142{\pm}2.0m.y.$). Electrum-galena-sphalerite mineralization was deposited in three stages of quartz and calcite veins. Quartz sulfide-bearing stage I and II evolved from initial high temperatures (near $360^{\circ}C$)to later lower temperatures(near $220^{\circ}C$)from lower salinity fluids(1.0 to 3.2 wt.% NaCl eq.). Fluid inclusion data from the post ore carbonate stage reflects much cooler($110^{\circ}$ to $180^{\circ}C$). Evidence of boiling indicates pressure of<85 bars, corresponding to depths of 400m to 1050m assuming lithostatic and hydrostatic loads. Au-deposition was likely a result of boiling, coupled with declining temperatures. The ${\delta}^{34}S$ $H_2S$ values calculated for sulfides are consistent with an igneous source of sulfur with a ${\delta}^{34}S_{{\Sigma}S}$ value near 4.0‰.

• Economic and Environmental Geology
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• v.13 no.1
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• pp.21-27
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• 1980

${\delta}^{13}C$ and ${\delta}^{18}O$ values were determined for the Paleozoic limestones (Great Linestone Series) from the Taebaegsan region and the age-unknown limestones (Janggun Formation) from the Janggun mine, Korea. Limestones of the Great Limestone Series exhibit a range of carbon isotopic composition from -4.5 +1.3‰ with a mean ${\delta}^{13}C$ value of -1.1‰, relative to the PDB standard, and of oxygen isotpic composition from +8.8 to +23.3‰ with a mean ${\delta}^{18}O$ value of +16.0‰, relative to the SMOW, falling into the normal marine limestone range according to Keith and Weber (1964), and Degens and Epstein(1964). Carbon isotopic composition of limestones of the Great Limestone Series becomes progressively lighter from Pungchon limestone of middle Cambrian age to mid-Ordovician Maggol limestone, possibly due to change in depositional environment in the Taebaegsan basin. Variation in isotopic composition of limestones from Hwajeol to Dumugal formation offers the possibility or deposition in shallow sea environment, in which fresh waters were added in several stages. Janggun limestone of unknown age may be corelated with the Paleozoic limestones of Great Limestone Series as infered from the istopic composition ranging from -2.8 to + 0.7‰ of ${\delta}^{13}C$ and +13.4 to +22.4‰ of ${\delta}^{18}O$.

• Economic and Environmental Geology
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• v.24 no.4
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• pp.363-378
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• 1991

Field and microscopic evidence, XRD,EPMA and chemical data suggest that parent rock of talc ore deposits of Yesan district was originated from ultramafic igneous rock. Parent rock can be divided into serpentinized dunite, serpentinized peridotite, metagabbro, amphibolite and hornblende schist. The ore deposits are highly sheared, and show many evidences of hydrothermal alteration and metamorphism at the greenschist and albite-epidote amphibolite facies. The process of steatitization is variable depending upon the composition, and the degree of alteration and metamorphism of the parent rocks. Steatitization can be divided into two processes with or without serpentinization. The parent rocks with serpentinization are serpentinized dunite, serpentinized peridotite and metagabbro, showing the following alteration process; olivine ${\rightarrow}$ serpentine${\rightarrow}$ talc. The rocks without serpentinization are amphibolite and hornblende schist showing the following sequence; hornblende${\rightarrow}$ chlorite${\rightarrow}$ talc. Formation of talc deposits is summarized as following six stages; I) Intrusion of ultramafic rocks, 2) autometamorphism, 3) metamorphism at greenschist and albite-epidote-amphibolite facies, 4) brittle deformation, 5) hydrothermal alteration, 6) purification of low-grade talc by late dyke intrusion.

• Economic and Environmental Geology
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• v.29 no.1
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• pp.1-11
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• 1996

Magnetite ores of the Janggun mine are embedded in dolomitic limestone of the Janggun Limestone Formation contacting with Chunyang granite, and are closely associated with skarn minerals. Mineralization of magnetite deposits can be divided into two stages as deep-seated skarn stage and shallow hydrothermal replacement stage. Mineralogies of skarn stage consist of magnetite, pyrrhotite and base-metal sulfides, and those of hydrothermal stage is base-metal sulfides, native bismuth, bismuthinite, tetrahedrite, boulangerite, bournonite and stannite. The FeS mole % in sphalerite and As atom % in arsenopyrite range from 22.47 to 26.30 and from 31.39 to 31.66 in skarn stage, and are from 17.54 to 32.54 and 28.87 to 30.70 in hydrothermal stage, respectively. Based on mineralization characteristics, mineral assemblages, chemical compositions and thermodynamic considerations, formation temperatures, sulfur fugacities ($-logf_2$), pH and oxygen fugacity ($-logfo_2$) estimated to be from 345 to $382^{\circ}C$, from 8.1 to 9.7atm, from 6.5 to 7.2 and from 30.5 to 31.2atm in the skarn stage, respectively, and temperature and $-logfs_2$ are from 245 to $315^{\circ}C$ and from 10.4 to 13.2atm in the hydrothermal stage.

• Economic and Environmental Geology
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• v.15 no.1
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• pp.1-16
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• 1982

Many skarn type iron ore deposits are distributed in Kimhae-Mulgeum area of Gyeongnam Province. Integrated field, mineralogic, geochemical and fluid inclusion studies were undertaken to illustrate the character and origin of the ores in this area. The iron ore deposits in this area are NS or NNE trending fracture filling magnetite veins which are developed in andesitic rocks near the contact with late Cretaceous micrographic granite bodies. Symmetrically zoned skarns are commonly developed in the magnetite veins of this area. Zoning of skarn from center to margin of the vein are as follows; garnet quartz skarn-epidote skarn-epidote orthoclase skarn-altered andesitic rocks. Major ore mineral is magnetite and small amount of hematite, pyrite, pyrrhotite, chalcopyrite and sphalerite are associated. Vein paragenesis reveals four depositional stages; 1) skarn stage, 2) iron sulfide and oxide stage, 3) skarn stage, 4) sulfide stage Minute halite-bearing polyphase inclusions and liquid inclusions are contained in quartz. Filling temperatures range from $257^{\circ}$ to $370^{\circ}C$.

• Economic and Environmental Geology
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• v.20 no.2
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• pp.107-118
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• 1987

The south ore deposits of the Dunjeon gold mine is a fissure-filling vein emplaced in the granitoids, skarnized and hornfelsified rocks of Ordovician Dumudong formation. The vein mineral paragenesis is complicated by repeated fracturing but three distinct depositional stages can be recognized; (1) base metal sulfides stage, (2) base metal sulfides, antimony-bismuthsulfosalts and native metals stage, (3) barren carbonates stage. Gold was mainly deposited in stage II. Fluid inclusion data indicate that fluid temperatures were from $310^{\circ}C$ to $402^{\circ}C$ during stage I and then declined steadily to $148^{\circ}C$ in the closing late stage III. Salinities were in the range of 0.4 to 5.0 equivalent weight percent NaCl and do not reveals any systematic trend through stag I, II and III. Ore mineralogy suggests that temperatures and sulfur fugacities in the earlier stage II were in the range of $340^{\circ}C$ to $360^{\circ}C$, $10^{-8}$ to $10^{-9}$ atm. respectively and then declined steadily to the range of $185^{\circ}C$ to $200^{\circ}C$ and $10^{-17}$ to $10^{-19}$atm. in the later stage II.

• Economic and Environmental Geology
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• v.20 no.4
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• pp.261-271
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• 1987

Muguk gold deposits are composed of quartz veins emplaced along faults in Mesozoic granodiorite. General strikes and dips of the veins are $N15{\sim}20^{\circ}W$ and $70{\sim}80^{\circ}NE$. Associated ore minerals are pyrite, arsenopyrite, sphalerite, galena, chalcopyrite, pyrrhotite, native silver, argentite, tetrahedrite and electrum. Vein mineral paragenesis is complicated by repeated fracturing, but five distinct depositional stages can be recognized. Electrum grains are associated mainly with sulfide bands formed along both margins of pale pink quartz of stage 3, and with patches of pyrite aggregate of stage 4. Before the close down in 1972, Muguk gold mine yielded more than 8 tons of gold of which major portion was produced from the No.2 vein. No.2 vein, extending about 1,500m laterally, was exploited to a depth of about 750m. In 1984, Young-poong mining company acquired the mining property and began geologic mapping, geochemical and geophysical exploration, diamond drilling and exploration tunnelling around the mine area to seek for other rich gold-bearing quartz veins. As the Samhyungje vein was disclosed to be the most rich vein, exploration works were focussed on the Samhyungje vein. As of August 1987, 22,338m of diamond drilling and 9,652m of exploration tunnelling have been undertaken. Owing to the successful result of exploration, the Muguk mine commenced normal operation on January 1987, treating 5,500 tons of ore per month.