• Economic and Environmental Geology
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• v.22 no.2
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• pp.117-127
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• 1989

Devonian Geochang foliated granite and Jurassic plutonic rocks intrude Precambrian metamorphic Complex at Geochang area, southern part of the Korean Peninsular. Among them hornblendes from four Jurassic plutonic bodies which have had no trace of metamorphism or deformation since their intrusion were dated by K-Ar method. Hornblende gabbro dike which intruded Anorthosite of unknown age revealed $204{\pm}10Ma$, and hornblende granite and hornblende-biotite granodiorite were $178{\pm}9Ma$ and $181{\pm}9Ma$, repectively. Also, hornblende diorite which partly showing primary foliations were $178{\pm}9Ma$, so igneous activity of Geochang area, northern part of Jirisan, were active about 180 Ma before. Microprobe data of dated hornblends and other major constituent minerals such as plagioclases and biotites were also reported, and their chemical composition showed systematic changes in terms of lithologic types.

• Economic and Environmental Geology
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• v.34 no.5
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• pp.437-446
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• 2001

Zoned epidotes formed by the propylitic alteration of the Bobae sericite deposit in western Pusan show complex compositional zoning patterns, such as multiple growth zoning, oscillatory zoning, patchy zoning and irregular zoning. The complex zoned epidote, in general, shows AI-rich cores and Fe-rich rims. Pistacite component (Ps) in the epidote ranges from 18.5 to 74.3 mot.%. Remnant textures in multiple growth zoning indicate that the earlier zone was partially resorbed prior to growth of later one. Multiple growth zoning and oscillatory zoning suggest that hydrothermal system underwent rapid changes and fluctuations in fluid chemistry, redox condition, or temperature.

• Economic and Environmental Geology
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• v.31 no.6
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• pp.527-534
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• 1998

Excavation of underground openings changes stress distribution around the opening. The survey of this disturbed zone in excavation is very important to design and construct underground facilities, such as tunnel, gas and oil storage, power plant and disposal site of high- and low-level radioactive wastes. This paper presents a zoning of rock masses with tunnel excavation using PS logging. Compressional and shear wave velocities are measured in boreholes drilled in the tunnel wall, which was constructed with blasting and/or machine excavation. The disturbed zone in excavation can be estimated by comparing PS logging data with a tomographic image of compressional wave velocity and compressional and shear wave velocities of core samples. In the side wall of tunnel, the disturbed zone reaches 1.5 m and 1.0 m in thickness for blocks of blasting and machine excavations, respectively. In the roof of tunnel, however, the disturbed zone is 1.0 m and 0.75 m thick for the two blocks. These results show that the width of the disturbed zone is larger in the side wall of tunnel than in the roof, and 1.3 to 1.5 times larger for the blasting excavation than for the machine excavation.

• Economic and Environmental Geology
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• v.29 no.2
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• pp.159-170
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• 1996

The gold-silver deposits of the Nakcheon, Eunchi and Jungbong mine in the northern Taebagsan mining district are composed of fissure fil1ing veins emplaced in Precambrian meta-sediments and Jungbongsan granite. Based on the changes of ore texture and mineralogy, ore mineral chemistry, fluid inclusion and mineralizing condition, a regional zoning is recognized from the Nakcheon to the Eunchi and Jungbong ore deposits, and this trend of zoning is also recognized by stable isotope compositions. Stable isotope compositions show that the source of su1fur and carbon is mainly igneous origin, and the water of ore fluid in the Nakcheon ore deposits is mainly magmatic origin but much of meteoric water is involved in ore fluid of the Eunchi and Jungbong ore deposits. The ore deposits of study area is polymetallic meso to epithermal type genetically related to the acidic igneous pluton. Due to the differntial erosion level and mineralized depth, each ore deposits has a slightly different characteristic of mineralization; The Nakcheon ore deposits belong to meso-epithermal type, but the Eunchi and Jungbong ore deposits belong to epithermal type.

• Journal of Energy Engineering
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• v.6 no.2
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• pp.129-136
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• 1997

This paper presents a new economic load dispatch considering atmospheric emissions such as NOx and SO$_2$caused by the operation of fossil-fueled thermal generation in power systems. The proposed method is described for scheduling their output of thermal power units so as to comply with total emission constraint, area emission constraint and the both of those constraints. Also, by using a trade-off curve, representing all dispatch alternatives and conflict between the emission and the fuel cost, the sensitivity analysis of the emission and the fuel cost is applied to this algorithm. By the way, this proposed method is analyzed how dispatch changes as a function of the total environmental cost, and as a function of the relative weighting of individual environmental insults, e.g, NOx and SO$_2$. By applying the proposed method to the system, the usefulness of this method is verified.

• Economic and Environmental Geology
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• v.26 no.1
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• pp.29-40
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• 1993

Several vermiculite deposits occur as the alteration product from phlogopite in ultramafic rock, in the Hongseong and Cheongyang area, South Korea. Some quarries show well-defined weathering profile. Samples collected from those quarries were examined by XRD and chemistry to define a vertical variations in mineralogy and chemistry of the weathering profile developed on ultramafic rocks. The analysis by X-ray diffractometry showed that mineral compositions changed continuously as depth of profile increasing, the vermiculite-the phlogopite/vermiculite interstratified-the phlogopite. Chemical analysis of bulk samples in altered zone revealed that regardless of composition and kinds of mineral in the rock, there are significant increase of MgO, CaO and $H_2O$, and decrease of K as depth of profile decrease reflecting the characteristics in vermiculitization. Also, there was a tendency that weathering indicies of each sample horizon change gradually with increasing depth. This tendency can be explained as variations of degree of vermiculitization. The regular changes of mineralogical and chemical composition in vertical profile suggest that weathering is the most important process in vermiculitization in this area.

• Economic and Environmental Geology
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• v.21 no.3
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• pp.209-221
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• 1988

The ore deposit of the Ohtani mine is one of repesentatives of plutonic tungsten-tin veins related genetically to acidic magmatism of Late Cretaceous in the Inner zone of Southwest Japan. Based on macrostructures of vein filling on the order of ore body, three major mineralization stages, called stage I, stage II, and stage ill from earliest to latest, are distinguished by major tectonic breaks. The alteration zories are characterized by specific mineral associations in pseudomorphs after biotite. The alteration zones can be divided into two parts, i. e. a chlorite zone and a muscovite zone, each repesenting mineralogical and chemical changes produced by the hydrothermal alteration. The chloritic alteration took place at the beginning of mineralization, and muscovite alteration in additions to chloritic alteration took place at stage II and ill. The alteration zones are considered to be formed by either of two alteration mechanism. 1) The zones are formed by reaction of the rock with successive flows of solution of different composition and different stage. 2) The zones are formed contemporaneously as the solution move outward. Reaction between the solution and the wall-rock results in a continuous change in solution chemistry. The migration of the successive replacement of the fresh zone$\rightarrow$the chlorite zone$\rightarrow$the muscovite zone may have transgressed slowly veinward, leaving metasomatic borders between the different zones.

• Economic and Environmental Geology
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• v.7 no.1
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• pp.1-21
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• 1974

From the point of view of geological history, the land of South Korea is regarded as the subject of processes of the changes in formations of several geological blocks such as Kyonggi massif, Yeongnam massif, Taebaegsan basin, Kyungsang basin and so on. Through the long period of geological chronology, the present topography and geotectonics have been formed by the complicate interactions of epirogenetic movements, magmatism, orogenesis, differential vertical movements, metamorphism and sedimentation. The reason of the crust movements mentioned above, is suppossed that the Pacific and West Pacific plate have subducted directly or indirectly into the East Asia plate. This fact can be endorsed by the results of the studies on the heat flow, gravity anomaly, absolute age dating, tectonic lineation, lithofacies and the temperature of hot spring in South Korea. The formations of metal ore deposits as well as other geological processes can be determined by the mechanical control of the plates and be divided into several systematic patterns. The investigation of about 110 metal mines in South Korea shows the following results. (1) Plate boundary volcanic type is about 28% (2) Plate boundary plutonic type is about 44% (3) Intraplate sedimentary type is about 26% (4) Intraplate magmatic type is about 2%.

• Economic and Environmental Geology
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• v.24 no.3
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• pp.219-226
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• 1991

High quality quartz crystals are grown in 0.5N NaOH + LiOH solution on the seed crystal at $370-395^{\circ}C$ and $1200-1300kg/cm^2$ condition. Growth rates are determined by the crystal thickness grown on the seed crystals with Z(0001) and X($11\bar{2}0$) direction. Relatively high growth rate of Z(0001) direction gradually changes as the temperaure difference (${\Delta}$ Ti) between growth and dissolution zones from 25 to $10^{\circ}C$. The X axis direction is affeced by ${\Delta}$ Ti, and +X($11\bar{2}0$) direction shows a high growth rate than -X($\bar{1}\bar{1}20$) direction. According to the variation with kinds of solutions used, the crystal growth that in NaOH solution is found to be slower than that in $Na_2CO_3$ solution. However, for the case in the NaOH solution mixed with LiOH, it shows a favorable growth rate in terms of grown crystal quality.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.435-443
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• 2018

Climate technology applied to address climate change requires a comprehensive review such as environmental and social acceptability in addition to economic feasibility. Not only mitigation and adaptation technologies, but also integration of climate technologies into a business model with other relevant technologies including ICT, finance, and policy instruments could enhance technical, economic, and environmental performances to respond to climate changes. However, many climate projects (and business models) are currently not designed to consider adequately complex climate?related issues. In addition, there is a lack of research on assessment systems that can comprehensively evaluate business feasibility of such models. In this study, we developed a system consisting of nine major indicators in four fields to assess climate technology-based business models. Each indicator was weighed using the analytic hierarchy process (AHP) for systematic assessment of business models. The process can be utilized as a tool to guide improvement of climate technology business models.