• Title/Summary/Keyword: Geosciences

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Late Pleistocene Fluvial Sequence in South Korea

  • Kim, Ju-Yong;Yang, Dong-Yoon;Nahm, Wook-Hyun;Lee, Yung-Jo;Park, Ji-Hoon
    • The Korean Journal of Quaternary Research
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    • v.18 no.2 s.23
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    • pp.33-42
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    • 2004
  • In South Korea a Pedo-sedimentary Sequence(PS) indicating the Last Glacial Maximun(LGM) is typified y a brown to dark brown, relatively stiff paleosol layers formed by repetitive freezing and thawing processes which in turn left characteristi glossic textures in soil-solum, polygolnal structures with a flagipans, vertical soil wedges or freezing cracks, and horizontal foliations, As a pre-LGM sedimentary sequences (older than 25Ka), the Old Fluvial Sequence(OFS) overlain by the Slope Sedimentary Sequence(SS) are distributed commonly at the base level higher than 14-15m above present river-bed along the major river basin. After the LGM (ca. 18Ka), the Young Fluvial Sequence(YFS) appears at an altitude ascending order of sedimentary profiles. In this fluvial organic muds of Jangheungri site(Jinju), Sorori site(Cheonwon), and Youngsan estruarine rivermouth(Mokpo) were exemplified in order to interpret their formation ages and environments. As result of $^{14}C$ datings, the formation ages of te organic muds are Boelling to Alleroed (MIS-1). These organic muds were fomed in fluvial backswamp or local pond/bog in response to shifting fluvial system. On the basis of palynological production dominant with Abies/Picea-Betula and Ranunculaceae, Compositae, Cyperaceae, and Graminae, it was interpreted that more boreal to subboreal condition was prevailed rather than temperate like today during the formation of organic muds and soil moisture condition was a repetition of wet and dry condition.

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Utilization of Mine failings from the Jeonju-Il Mine (전주일(全州一) 금속광산(金屬鑛山) 폐광미(廢鑛尾)의 활용(活用) 방안(方案) 연구(硏究))

  • Jeong, Soo-Bok;Chae, Yeung-Bae;Hyun, Jong-Yeong;Kim, Hyung-Seok;Yoon, Sung-Moon
    • Resources Recycling
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    • v.16 no.1 s.75
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    • pp.44-53
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    • 2007
  • The Jeonju-Il mine tailings contain large quantities of $SiO_2\;and\;Al_2O_3$ and lesser quantities of metallic components. In this study, we studied about the possibility of using mine tailings as a raw material in various industries. it was found that the sintered mine tailings had a good quality in every respect such as chromaticity, firing shrinkage and water absorption etc. Therefore if can substitute clay mineral in the ceramic industry. Also it can substitute about 2.94% of the raw materials of ordinary portland cement. We can use the coarse tailing as the fine aggregate for the ready-mixed mortar; and the fine tailing, as the filler for the bituminous paving mixture; because both products were not only suitable for Korea industrial standard in quality, but also environmentally harmless.

Global Trend of Cement Production and Utilization of Circular Resources

  • Lim, Chaeyeon;Jung, Euntae;Lee, Seongho;Jang, Changsun;Oh, Chaewoon;Shin, Kyung Nam
    • Journal of Energy Engineering
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    • v.29 no.3
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    • pp.57-63
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    • 2020
  • In this paper, we reported that the global trend of cement production and utilization as raw materials and as a fuel. As we know, cement is one of the significant materials required for the construction industry. The recent trend of rising urbanization, both the cement and construction industry played a vital role. The cement industry is a major sustainable infrastructure for the countries. Currently, China producing cement half of the world's cement production. During the year 2018, Korea producing cements nearly 57.5 million metric tons. Waste materials are used as circular resources and also having tremendous benefits for cement production. Another important use of these circular resources is fuel for the cement industry. There is a large potential benefit of the cement industry, but it's creating a severe environmental threat. The cement industry contributes to the major emissions of CO2. This leads the global warming. As per the Paris agreement, the Korean government initiated the recycling policy of waste materials and also the utilization of circular resources for the prevention of limited natural resources and also the global warming effect.

Applicability of Fuzzy Logic Based Data Integration to Geothermal Potential Mapping in Southern Gyeongsang Basin, Korea (경상분지 남부지역의 지열 부존 잠재력 평가를 위한 퍼지기반 자료통합의 적용성 연구)

  • Park, Maeng-Eon;Baek, Seung-Gyun;Sung, Kyu-Youl
    • Economic and Environmental Geology
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    • v.40 no.3 s.184
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    • pp.307-318
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    • 2007
  • The occurrence of geothermal water has high correlates highly with fossil geothermal system. A fuzzy logic based data integration is applied for geothermal potential mapping in the Southern Gyeongsang Basin which is distributed in the regional fossil geothermal system. Several data sets are related with the origin and distribution of fossil geothermal system, such as the geological map, the density of lineaments, the aerial survey map of magnetic intensity, the map of hydrothermal alteration, the distribution density of hydrothermal mines, which were collected as thematic maps for the integration. Fuzzy membership functions for all thematic maps were compared to the locations of the spa hot springs, which were used as ground-truth control points. After integrating all thematic maps, the results of gamma operator (${\gamma}=0.1$) was showed the highest success rate, and new geothermal potential zone is prospected in some area.

LA-ICP-MS U-Pb Zircon Age of the Granite Gneiss from Jeungsan-Pyeongwon Area of North Korea (북한 증산-평원지역 화강편마암의 LA-ICP-MS U-Pb 저콘 연대)

  • Song, Yong-Sun;Park, Kye-Hun;Lee, Ho-Sun;Lin, Cao;Yuji, Orihashi
    • The Journal of the Petrological Society of Korea
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    • v.18 no.2
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    • pp.171-179
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    • 2009
  • LA-ICP-MS U-Pb zircon age was determined from the granite gneiss from Jeungsan-Pyeongwon area located to the west of Pyeongan Basin, North Korea, yielding concordant age of $1,873{\pm}19(2{\sigma})$Ma interpreted as Paleoproterozoic granitic magmatism. Considering relatively precise data reported recently using SHRIMP and LA-ICP-MS, ages around 1,870 Ma have been most frequently reported from Precambrian basement rocks of Korean peninsula, including Yeongnam, Gyeonggi, and Nangnim massifs altogether. Geologic events of this period are interpreted as not only granitic magmatism but also hightemperature regional metamorphism depending on their localities. The magmatic and regional metamorphic events of similar periods have also been reported from neighboring cratons of both North China and South China. Therefore, we need more data and efforts to decipher correlation between Precambrian basements between Korea and China.