• Title/Summary/Keyword: Natural rocks

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The Stone Cave Temples in Silla Era (신라시대(新羅時代)의 석굴사원(石窟寺院))

  • Chin, Hong-Sup
    • Journal of the Korean Society of Costume
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    • v.5
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    • pp.13-22
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    • 1981
  • The stone caves in Korea, though they were first influenced by Chinese cave temples, were not made same with their predecessors in style. Nearly all Korean stone caves are the simulated ones built artificially, and they are divided into the following: A. The caves that were made up with several pieces of natural rocks with some wood works done over them to cover the open spaces between the rocks. B. Wood works were added in front of the rock-cut images of Buddha in order to construct the cave. C. The men-made caves Suk-kul-am in Kyung-ju is well-known among the above kind of the caves. In short, Korean stone caves have their distinction in which they were inspired by the Indian and Chinese examples and developed their own styles to meet the specific conditions and restraints of the Korean mountains. The extant Silla cave temples are classified in the following four groups: 1) The type of Shin-sun-sa(神仙寺) at Kyung-ju 2) The type of Ka-heung-ri cave(可興里) at Yong-ju(榮州) 3) The type of Kun-wi cave(軍威) 4) The type of Suk-kul-am(石窟庵) at Kyung-ju

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Some Influences of Anisotropy in Clay Soil and Rocks

  • R.H.G.Parry
    • Proceedings of the Korean Geotechical Society Conference
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    • 1997.06c
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    • pp.1.2-22
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    • 1997
  • Anisotropic behaviour in soils and soft rocks may be either fabric of stress related ultra in practice is invariably a combination of both. Theoretical studies in the paper include tile iMluence oil untrained strength of assuming both the critical state and Mo21r-Coulomb concepts to hold, and the influence of elastic anisotropy oil predicted undrained effective stress paths. The predictions stemming from these theoretical concepts are examined in the light of evidence from triaxial compression and extension tests oil laboratory prepared, compacted and natural clays and from triaxial compression tests on clay shales. The experimental studies also show the Buence of sample orientation on untrained snear strength, as wen as the iIBluence of anisotropy old the effective stress angle cishearing resistance and of stress patn on measured stiffness.

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Estimation of Sediment Provenance Using Clay Mineral Composition in the Central Basin of the Ross Sea Continental Margin, Antarctica (남극 로스해 대륙주변부 중앙분지의 점토광물 조성을 통한 기원 추적)

  • Ha, Sangbeom;Khim, Boo-Keun;Colizza, Ester;Giglio, Federico;Koo, Hyojin;Cho, Hyen Goo
    • Ocean and Polar Research
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    • v.41 no.4
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    • pp.265-274
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    • 2019
  • To trace the provenance of fine-grained sediments in response to the growth and retreat of glaciers (i.e., Ross Ice Sheet) that affects the depositional process, various kinds of analyses including magnetic susceptibility, granulometry, and clay mineral composition with AMS 14C age dating were carried out using a gravity core KI-13-GC2 obtained from the Central Basin of the Ross Sea continental margin. The sediments mostly consist of silty mud to sand with ice-rafted debris, the sediment colors alternate repeatedly between light brown and gray, and the sedimentary structures are almost bioturbated with some faint laminations. Among the fine-grained clay mineral compositions, illite is highest (59.1-76.2%), followed by chlorite (12.4-21.4%), kaolinite (4.1-11.6%), and smectite (1.2-22.6%). Illite and chlorite originated from the Transantarctic mountains (metamorphic rocks and granitic rocks) situated to the south of the Ross Sea. Kaolinite might be supplied from the sedimentary rocks of Antarctic continent underneath the ice sheet. The provenance of smectite was considered as McMurdo volcanic group around the Victoria Land in the western part of the Ross Sea. Chlorite content was higher and smectite content was lower during the glacial periods, although illite and kaolinite contents are almost consistent between the glacial and interglacial periods. The glacial increase of chlorite content may be due to more supply of the reworked continental shelf sediments deposited during the interglacial periods to the Central Basin. On the contrary, the glacial decrease of smectite content may be attributed to less transport from the McMurdo volcanic group to the Central Basin due to the advanced ice sheet. Although the source areas of the clay minerals in the Central Basin have not changed significantly between the interglacial and glacial periods, the transport pathways and delivery mechanism of the clay minerals were different between the glacial and interglacial periods in response to the growth and retreat of Ross Ice Sheet in the Ross Sea.

Arsenic Occurrence in Groundwater of Korea (국내 지하수의 비소 산출양상)

  • Ahn, Joo-Sung;Ko, Kyung-Seok;Chon, Chul-Min
    • Journal of Soil and Groundwater Environment
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    • v.12 no.5
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    • pp.64-72
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    • 2007
  • Nationwide occurrence of arsenic in groundwater of Korea was investigated with the data from the groundwater quality monitoring stations. During 2001-2006, As has been quantitatively detected in 3.0 % of the total wells $(5.0{\sim}188{\mu}g/L)$, and its geographical distribution suggests 3 groups: an urbanized and industrialized area (Seoul and its neighbouring province), and two naturally occurring areas (Chungbuk and Gyeongnam provinces). Natural occurrence of As appears to be geologically related with Ogcheon metasedimentary rocks and Cretaceous volcanic rocks. Based on the results of the previous studies in the high As sites, the oxidation of sulfides can be a major control on As concentrations in groundwater in the mineralized and altered zone within the area of Cretaceous volcanic rocks. Desorption process under slightly high pH conditions may also be responsible for high As in groundwater in areas of Ogcheon metasedimentary rocks.

Reflectance of Geological Media by Using a Field spectrometer in the Ungsang Area, Kyungsang Basin

  • Kang, Kyung-Kuk;Song, Kyo-Young;Ahn, Chung-Hyun;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.17 no.2
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    • pp.165-181
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    • 2001
  • Using a field spectrometer having a spectral range of 0.4$\mu\textrm{m}$~2.5$\mu\textrm{m}$ with a spectral resolution of 1nm, the researchers measured the reflectance of granite, andesitic rocks, sedimentary rocks, and pyrophyllite ore in the Ungsang area, Kyungsang Basin, South Korea. Spectral characteristics of the geological media were investigated from the analysis. The in-situ measured sites were selected in well exposed rock outcrops. In case of unfavorable weather conditions, rocks were sampled and remeasured under natural solar condition. The reflectance of field data was measurd at three sistes for granite, six sites for andesitic rock three sites for sedimentary rocks, and two sites for pyrophyllite ore. The vibrational absorption bands for pyrophyllite are detected in the spectral range of 2.0$\mu\textrm{m}$~2.5$\mu\textrm{m}$. The absorption band for granites in study area is not distinctive. The reflectance measured under normal field conditions showed strong absorption at wavelengths of 1.4$\mu\textrm{m}$ and 1.9$\mu\textrm{m}$ due to the effect of moisture in the atmosphere. After the bands of 1.4$\mu\textrm{m}$ and 1.9$\mu\textrm{m}$ were removed, Hull Quotient method was applied to characterize absorption bands. The reflectances of field data were calculated to estimate the band ratio corresponding to the Landsat TM and EOS Terra ASTER. The researchers suggest here that the TM band2, band3, band4, and band7 or ASTER band2, band3, band4, and band9 are the best combination for discriminating outcrops. The researchers tested and demonstrated using a Landsat TM image in the study area. For geologic applications, decorrelation stretch is also an effective tool to enhance the exposed rock mass in images.

The Distribution Characteristics Analysis of Block Stream and Talus Landform by Using GIS-based Likelihood Ratio in the Honam Region (GIS 기반 우도비를 이용한 호남지역 암괴류와 애추지형의 분포 특성 분석)

  • JANG, Dong-Ho;Kim, ChanSoo
    • Journal of The Geomorphological Association of Korea
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    • v.25 no.2
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    • pp.1-14
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    • 2018
  • The main objective of this paper is to classify properties of the locational environment for each debris type by calculating likelihood ratio based on the correlation between the distributions for each type of debris landform. A total of 8 thematic maps, like as elevation, slope, aspect, curvature, topographic wetness index (TWI), soil drainage, geology, and landcover including with GIS spatial information generally used in this type of debris landform analysis. The results of this study showed that the block stream had a high likelihood ratio compared to talus in areas with relatively high elevation; and concerning slope, the block stream had a high likelihood ratio in a relatively low region than talus. Concerning aspect, a clear correlation could not be analyzed for each debristype, and concerning curvature, the block stream displayed a developed slope on the more concave valley than the talus. Analysis concerning TWI, the block stream displayed a higher likelihood ratio in wider sections than talus, and concerning soil drainage, the talus and block stream both displayed a high likelihood ratio in regions with well-drained soil. The talus displayed a high likelihood ratio in the order of metamorphic rocks, sedimentary rocks, and granite, while the block stream displayed a high likelihood ratio in the order of volcanic rocks, granite, and sedimentary rocks. In addition, concerning landcover, the likelihood ratio had the most concentrated distributed compared to natural bare land only concerning talus. Based on the likelihood ratio result, it can be used as basic data for extracting the possible areas of distribution for each debris type through the GIS spatial integration method.

Study on their Presentation Types and Exhibition Methods in National History Museum - Focused on National History Museum In Korea - (자연사박물관의 전시매체유형 및 연출기법에 관한 고찰 - 국내자연사박물관사례를 중심으로 -)

  • Lee Jong-Sook;Kim Kyung-Mi;Yoo Dong-Lim
    • Korean Institute of Interior Design Journal
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    • v.15 no.1 s.54
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    • pp.131-138
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    • 2006
  • This paper compares presentation methods which are characteristic among museums of natural history in Korea. The different medium for exhibitions are divided into Specimen, Model or Panel Type Displays, Video Presentations, Sound, and Tactile Exhibits, and further classified as Fixed (A Type), Observable (B Type), or Performance Art (C Type) Displays. The museums we studied were the Seodaemun Museum of Natural History, Ewha Womans University Museum of Natural History, Seoul National Science Museum, Gyeryongsan Natural History Museum, the National Science Museum, Mokpo Natural History Museum, and the JejuDo Folklore and Natural History Museum. A study of these museums' approaches to display composition, and exhibition methods according to their exhibit types and contents, revealed the following results: The museums of natural history rely more on Fixed type displays to show information, with appropriate uses of the Observable and the Performance Art type exhibitions. Better utilization of appropriate medium is desired for display contents of Astronomy Space Earth, Minerals Rocks Geology, Animals, Plants, Insects, Prehistoric Organisms Environment, and Anthropology.

A Preliminary Study for a Glass Geological Reference Material Using Obsidian (흑요암을 이용한 유리 지질 표준물질에 대한 예비 연구)

  • Jin, Mi-Eun;Jwa, Yong-Joo;Park, Sang Gu;Sun, Gwang Min
    • Korean Journal of Mineralogy and Petrology
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    • v.33 no.1
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    • pp.65-71
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    • 2020
  • Glass reference materials have been essentially used for precise geochemistry analytical techniques. In order to make up for the drawback of synthetic glass reference materials, which have the high uncertainty caused by the difference in composition of natural rocks, we introduce a glass geostandard using natural glass. The NK-B1G sample, which comes from the Baekdusan obsidian, is a natural glassy rock that contains only few crystals such as microlites or inclusions. We examined the feasibility of the sample as a reference material for microanalysis like EPMA or LA-ICPMS.

A Study on the Establishment of Guidances for Natural Stone Arrangements (자연석 사용 개선을 위한 설계 및 시공 기준 설정에 관한 연구)

  • 구본학;김용규;안동만
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.4
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    • pp.94-100
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    • 1999
  • Stone is one of the oldest material for construction and artistic works. This study investigates the current use of stones in landscape constructional works, and the design criteria to advance the arts of natural stone arrangements. Thirty four experts and thirty two others were surveyed with various photos of simulated construction works of natural stone arrangements fond improved design guidelines. Major findings are as follows: -The payment for the use of stones ranges approximately 5 to 10% of total cost of landscape constructional works. More stones may be used when better retailing system is introduced, working skill is standardized, and more of the substitute natural stones made of blasted rocks are provided and the cost goes down. -Preferences showed little difference for the mixed use of different sizes, colors and shapes of stones, and for the use of similar ones, in the construction of walls. This does not match with the current design guidelines. -Arranging three stones, which symbolizes heaven, earth, and human being, was the most preferred. As the supply of natural stones is limited and more substitute stones are used, it its needed to establish guidelines for the production of substitute stones. -Grasses are much more preferred between pavement stones than mortars. -In current practices, top of piled up natural stones is usually arranged level. More freely curved top lines are preferred to straight line.

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Weathering Characteristics of Rocks near Churyong Tunnel Site, Kyongbuk, using Geophysical and Geochemical Methods (경북 추령터널 부근 암석의 풍화특성에 관한 지구물리화학적 연구)

  • 서만철;김민규;최석원
    • The Journal of Engineering Geology
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    • v.4 no.3
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    • pp.269-281
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    • 1994
  • Microscopic study and X-ray diffraction analysis were carried out to find out rock type, tock forming minerals; and weathering characteristics of rocks at the constructing site of the churyong Tunnel, Kyongju-Gun, Kyongbuk. Seismic velocity and compressional strength were measured to evaluate mechanical properties of rock. The rock of the study area is Jurassic tuff consisting of clay minerals, crystals of quartz and feldspar, fragments of volcanic rocks and shale. Fresh tuff has compressional strength of about $443kg/\textrm{cm}^2$ and seismic velocity of about 3680m/sec in average. It is classified as soft rock. Rock fragment within tuff is andesite and it has compressional strength of about $2500kg/\textrm{cm}^2$ and seismic velocity of about 4340m/sec in average. It is classified as hard rock. A good linear relationship is found between compressional streangth and seismic velocity in both laboratory sample and in-situ rocks. Laboratory samples has seismic velocities faster about 1.5km/sec than those in-situ rocks. It is interpreted that joints, fractures, and water content in the in-situ rocks result in decreas of seismic velocity. As Tuff has more than 50% of clay minerals in matrix and shale fragments, it absorbs water easily in atmospheric condition. Therefore, though the rock in the study area is medium hard rock before weathering, it is weathered very easily in the case of exposure to natural environment, comparing with other rock.

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