• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.790-799
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• 2010

The Upper Devonian Grossmont Formation in Alberta, Canada reserves an estimated 50 billion cubic meters of bitumen and possess about 1/6 of the total bitumen resources in northern Alberta. However, unlike the overlying Athabasca oil sands, non conventional bitumen resources has not been developed as yet. The carbonate rocks of Grosmont Formation have been subject to various stages of diagenesis, including dolomatization and karstification with a strong effect on the distribution of porosity and permeability, which resulted in highly heterogeneous reservoirs. An extensive fracture logging and mapping was performed on total of six boreholes located in the study area to explore the characteristics of fracture geometry system and the subsurface structures of carbonates reservoir that holds bitumen. Fractal dimension was used as a measure of the statistical homogeneity of the fractured rock masses. The applicability of random Cantor dust, Dc, as a fractal parameter was examined systematically. The statistical homogeneity of fractured carbonates rock masses was investigated in the study area. The structural domains of the rock masses were delineated depthwise according to estimated Dc. The major fracture orientation was dominated by horizontal beddings having dip of $0-20^{\circ}$. Also, fractures having high dip angles existed with relatively low frequency. Three dimensional fracture network modeling for each structural domain has been performed based on fracture orientation and intensity, and some representative conceptual models for carbonates reservoir in the study area has been proposed. The developed subsurface conceptual models will be used to capture the geomechanical characteristics of the carbonates reservoir.

• 지구물리
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• 제7권4호
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• pp.255-267
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• 2004

석산 내의 절리구조를 정확하게 규명하는 것은 석재의 채수율 결정뿐만 아니라 체계적이고 효율적인 개발 계획 수립에 있어도 매우 중요하다. 또한 암맥 및 엽리 발달상태, 풍화 내지 변질정도, 구성 광물과 같은 암반의 성상은 석재의 재질을 평가하는 데 중요한 요소가 되고 있다. 따라서, 본 연구의 목적은 텔레뷰어 탐사 및 칼라 코어스캐너를 통해 절리구조 및 암반 성상에 대한 바람직한 정보를 제공하는 데 있다. 텔레뷰어 탐사는 경남 하동 반상 변정질 편마암 석산에서 천공된 7개의 시추공에 대해 수행되었으며, 그 시추코어들은 칼라 코어스캐너에 의해 디지털 이미지화 되었다. 텔레뷰어 이미지에서는 모든 종류의 절리들이 뚜렷하게 인식되고 있으며, 그의 연장 상태도 조사됨으로써 석산 내의 석재 품질을 파악하는 데 도움을 주고 있다. 한편, 고분해능(최대 20 pixels/mm) 코어 이 미지는 텔레뷰어 자료에서는 확인하기 어려운 광물의 입자 크기 및 분포, 엽리 발달상태 등과 같은 암반 성상에 대한 자세한 정보를 제공하고 있다.

• 자원환경지질
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• 제55권6호
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• pp.649-659
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• 2022

본 연구는 충주-괴산일대에 분포하는 기반암 중 화강암, 규암, 천매암, 편암, 편마암의 골재자원으로서의 활용도를 고찰하였다. 연구지역에 분포하는 화강암류는 쥬라기 흑운모 화강암이 주를 이루고, 규암층은 계명산층과 향산리 돌로마이트 석회암 상부에 분포하는 대향산규암층으로 이루어져 있다. 또한 천매암은 옥천대 황강리층을 구성하는 함력천매암질암이고, 편암은 옥천대 문주리층인 녹니석편암, 편마암은 서창리층 상부에 해당하는 반상변정편마암으로 이루어져 있다. 본 기반암들의 골재품질 평가요소로는 조립률, 흡수율, 단위용적질량, 절대건조밀도, 실적률, 공극률, 마모율, 안정성 등이 고려되었다. 본 기반암들의 골재품질 평가 결과 대부분이 기본 골재품질기준을 만족하는 것으로 나타났으며, 암종별 물성특성 분포범위는 다르게 나타났다. 화강암의 경우, 단위용적질량, 실적률, 공극률, 마모율에서 일부 만족하지 못하는 것으로 나타났으며, 편마암은 마모율에서, 편암은 공극률과 실적률에서 기준치를 벗어났다. 전반적인 골재자원으로서의 품질은 규암, 편마암 및 천매암이 우수한 품질을 보이는 것으로 분석되었다. 골재품질시험은 암석별로 개략적으로 이루어지지만 같은 암석이라도 광물의 형상(morphology)에 다라 달라질수있다. 따라서 골재자원의 품질평가를분석, 활용 할 때 암석-광물학적 연구를 병행한다면 더욱 효율적으로 활용이 가능 할 것이다.

• Journal of Preventive Medicine and Public Health
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• 제30권3호
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• pp.555-566
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• 1997

This study was carried out to evaluate the cytotoxicity of rock wool fibers(RWFs) such as cell division disturbance, chromosomal and DNA damage, and mutagenicity using cultured cells. RWFs were the man made mineral fibers. In order to find the correlation between the cytotoxicity of RWFs and the phagocytic capacity of cells, the phagocytic processes were observed using scanning electron microscope. Cell division disturbance by RWFs was evaluated by the formation of multinucleated giant cells. The chromosomal damage was evaluated by the micronucleus formation. For the evaluation of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) formation was measured utilizing calf thymus DNA. Mutagenicity was determined by the point mutation of HGPRT and the effect of RWFs on cell transformation was also observed. 1. Compared with the results of chrysotile, RWFs were no or little effect on the cell growth according to the results done by the tests of cell proliferation inhibition and relative plating efficiency. 2. The frequency of multinucleated giant cell formation was increased by the treatment of RWFs and it was dose-dependent. However, the effect of RWFs was weaker than that of chrysotile. 3. The number of micronuclei formed in the RWFs treated cells was between those of cells treated with chrysotile and those of untreated cells. 4. The 2 fold increase in the formation of 8-OH-dG in calf thymus DNA was observed in the cells treated with RWFs in the presence of $H_2O_2$. On the other hand, chrysotile had no effect on the 8-OH-dG formation. 5. RWFs had no effect on the HGPRT point mutation and cell transformation. These results showed that RWFs could induce chromosomal damage, cell division disturbance and oxidative DNA damage in the RWFs treated cells.

• 한국해양학회지
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• 제20권2호
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• pp.40-48
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• 1985

강원도 정선군 회동리 일대와 행매동일대에 분포하는 조선누층군의 회동리 석 회암층(사일무리아기)에 대한 고퇴적환경의 규명을 목적으로 암상과 퇴적구조에 대 한 연구가 시행되었다. 연구 결과 회동리층은 불용성 잔류물의 함량이 많고 (평균17 %), 화석의 산출이 빈약한 mudstone facies와 wackestone facies로 구성되며 crypt-algalaminates, bird's eye structures, evaporite pseudomorphs, bioturbated mottle structures, detrital quartz pockets, 및 cross bedding등의 특징적인 퇴적구 조가 나타나고 있음이 밝혀졌다. 회동리층의 이러한 퇴적구조들의 층서적 분포양상 과 암상적 특성을 종합하여 볼 때, 본 역의 회동리석회암층은 주로 고염분의 상조 대(supratidal zone)와 조간대(intertidal zone)에서 퇴적된 것으로 사료된다.

• 한국암반공학회:학술대회논문집
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• 한국암반공학회 2007년도 춘계학술발표회 논문집
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• pp.64-80
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• 2007

본 논문은 영동선 동백산역에서 도계역 사이를 연결하는 국내 최장터널(16.2km)인 솔안터널의 굴착사례를 소개하고자 한다.본 현장은 퇴적암지대로서 단층,공동 및 함탄층으로 구성된 복잡한 지질구조를 가지고 있다. 이러한 지질구조 중 석회암 지대에서 터널 굴착시 예기치 못한 유수에 의해 지반공학적 문제점이 발생하였다. 본 터널은 석회암층 내 공동 및 단층의 영향으로 지하수위의 저하 및 토사유실이 발생하여 지표침하를 가져왔다. 이에 따른 정밀조사를 통한 원인 분석과 대책을 소개하고, 석회암의 특성을 반영한 침하 재발방지방안을 제시하고자 한다.

• Structural Engineering and Mechanics
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• 제51권5호
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• pp.823-845
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• 2014

Success in the excavation of foundations is commonly known as being very important in asserting stability. Furthermore, when the subjected formation is rocky and the use of explores is required, the demands of successful blasting are multiplied. The quick and correct estimation of excavation's characteristics may help the design of building structures, increasing their safety. The present paper proposes a new classification system which connects blastability and rock mass quality. This new system primarily concerns poor and friable rock mass, heavily broken with mixture of angular and rounded rock pieces. However, it should concern medium and good quality rock mass. The Blastability Quality System (BQS) can be an easy and widely - used tool as it is a quick calculator for blastability index (BI) and rock mass quality. Taking into account the research calculations and the parameters of BQS, what has been at question in this paper is the effect of BI magnitude on a geological structure.

• 터널과지하공간
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• 제1권2호
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• pp.181-203
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• 1991

The effects of geologic structures such as rock joins and bedding planes on the thermal conductivity of a discontinuous rock mass are studied. The expressions for the equivalent thermal conductivities of jointed rock masses are derived and found to be anisotropic. The degree of anisotropy depends primarily on the thermal properties contrast between the joint phase and surrounding intact rock, the joint density expressed as volume fraction and the inclination angle of the joint. Within the context of 2-dimensional finite element heat transfer scheme, the isotherms around a circular hole are analyzed for both the isotropic and anisotropic rock masses in 3 different thermal boundary conditions. i.e. temperature, heat flux and convection boundary conditions. The temperature in the stratified anisotripic rock mass is greatly influenced by the thermal properties of the rock formation in contact with the heat source. Using the excavation-temperature coupled elastic plastic finite element method, analyzed is the thermo-mechanical stability of a circular opening subjected to 10$0^{\circ}C$ at a depth of 527m. It is found that the thermal stress concentration was enough to deteriorate the stability and form a plastic yield zone around the opening, in contrast to the safety factor greater than 2 resulted form the excavation-only analysis.

• Geomechanics and Engineering
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• 제14권5호
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• pp.439-451
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• 2018

The stress path characteristics of surrounding rock in the formation of gob were analysed and the unloading was solved. Taking Chengchao Iron Mine as the engineering background, the model for analysing the instability of deep gob was established based on the mechanism of stress relief in deep mining. The energy evolution law was investigated by introducing the local energy release rate index (LERR), and the energy criterion of instability of surrounding rock was established based on the cusp catastrophe theory. The results showed that the evolution equation of the local energy release energy of the surrounding rock was quartic function with one unknown and the release rate increased gradually during the mining. The calculation results showed that the gob was stable. The LERR per unit volume of the bottom structure was relatively smaller, which mean the stability was better. The LERR distribution showed that there was main energy release in the horizontal direction and energy concentration in the vertical direction which meet the characteristics of deep mining. In summary, this model could effectively calculate the stability of surrounding rock in the formation of gob. The LERR could reflect the dynamic process of energy release, transfer and dissipation which provided an important reference for the study of the stability of deep mined out area.

• 자원환경지질
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• 제33권5호
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• pp.405-415
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• 2000

This study was carried out to understand the formation of acid mine drainage (AMD) by pyrophyllite (so-called Napseok)-rainwater interaction (weathering), dispersion patterns of heavy metals, and patterns of mixing with non-polluted water in the Tongnae pyrophyllite mine. Based on the mass balance and reaction path modeling, using both the geochemistry of water and occurrence of the secondary minerals (weathering products), the geochemical evolution of AMD was simulated by computer code of SOLVEQ and CHILLER. It shows that the pH of stream water is from 6.2 to 7.3 upstream of the Tongnae mine. Close to the mine, the pH decreases to 2. Despite being diluted with non-polluted tributaries, the acidity of mine drainage water maintains as far as downstream. The results of modeling of water-rock interaction show that the activity of hydrogen ion increases (pH decreases), the goncentration of ${HCO_3}^-$ decreases associated with increasing $H^+$ activity, as the reaction is processing. The concentration of ${SO_4}^{2-}$first increases minutely, but later increases rapidly as pH drops below 4.3. The concentrations of cations and heavy metals are controlled by the dissolution of reactants and re-dissolution of derived species (weathering products) according to the pH. The continuous adding of reactive minerals, namely the progressively larger degrees of water-rock interaction, causes the formation of secondary minerals in the following sequence; goethite, then Mn-oxides, then boehmite, then kaolinite, then Ca-nontronite, then Mgnontronite, and finally chalcedony. The results of reaction path modeling agree well with the field data, and offer useful information on the geochemical evolution of AMD. The results of reaction path modeling on the formation of AMD offer useful information for the estimation and the appraisal of pollution caused by water-rock interaction as geological environments. And also, the ones can be used as data for the choice of appropriate remediation technique for AMD.