• 터널과지하공간
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• 제18권1호
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• pp.58-68
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• 2008

임하댐 비상여수로 터널 공사가 단층파쇄대가 포함된 화강암지역에 굴착되고 있는데 본 터널이 3련 터널임을 감안하여 터널이격거리, 터널막장간 이격거리를 검토하였으며 단층파쇄대가 여수로 터널의 안정성에 미치는 영향을 검토하였다. 이를 위해 여러 가지 지구물리학적 조사와 암반공학적 현장 실험을 실시하였다. 터널 막장간 이격거리는 최소 25 m 이상을 유지하면서 2터널의 선행 굴착이 적합하리라 판단되며 단층대의 영향을 받는 터널 만곡부의 3차원 수치해석결과 2터널의 천단변위 및 내공변위는 미미하며 숏크리트 최대 휨압 축응력, 숏크리트 최대전단응력, 록볼트 최대축력 등을 살펴보면 만곡부 굴착에 따른 응력집중은 미미하여 여수로 터널의 안정성에는 문제가 없는 것으로 판단되었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권5호
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• pp.34-40
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• 2015

It is reported that the intensity of rainfall will likely increase, on average, over the world on 2000. For water resources security, many studies for flow paths from rainfall or snowmelt to subsurface have been conducted. In Korea, few isotopic studies for characterizations of flow path have been undertaken. For a better understanding of how water derived from atmosphere moves to subsurface and from subsurface to stream, an analysis of precipitation and stream water using oxygen-18 and deuterium isotopes in a small watershed, Dorim-cheon, Seoul, was conducted with high resolution data. Variations of oxygen-18 in precipitation greater than 10‰ (δ¹⁸O_max = −1.21‰, δ¹⁸O_min = −11.23) were observed. Isotopic compositions of old water (groundwater) assumed as the stream water collected in advance were −8.98‰ and −61.85‰ for oxygen and hydrogen, respectively. Using a two-component mixing model, hydrograph separation of the stream water in Dorim-cheon was conducted based on weighted mean value of δ¹⁸O. As a result, except of instant dominance of rainfall, contribution of old water was dominant during the study period. On average, 71.3% of the old water and 28.7% of rainfall contributed to the stream water. The results show that even in the small watershed, which is covered with thin soil layer in granite mountain region, the stream water is considerably influenced by old water inflow rather than rainfall.

• 자원환경지질
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• 제18권3호
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• pp.247-251
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• 1985

The sulfide and carbonate mineral samples for sulfur and carbon isotope studies were collected from Sangdong, Geodo, Yeonhwa, Shinyemi and Janggun mines which are distributed in the Metallogenetic Province of the Taebaeg Mt. Region. The ${\delta}S^{34}$ values of molybdenite, pyrite, arsenopyrite, pyrrhotite, chalcopyrite, sphalerite and galena from the above mines are similar and within the range of +1.66 to +6.77‰ with the exception of chalcopyrite from Geodo mine ranging from -1.58 to 1.96‰, while the sulfide minerals are dominated by positive values between +3.05 and +5.08‰. It is suggested that the major sulfur source is genetically related to the Cretaceous granitic activity. The average ${\delta}C^{13}$ values of calcite from limestone, calcite from calcite vein in ore bodies and granite, and rhodochrosite from ore bodies are -0.60‰, -2.69‰ and -6.00‰, respectively. The data on carbon isotope compositions indicate that the calcite from limestone originated in marine environment, the rhodochrosite in hydrothermal solution, and calcite from calcite vein and granite in the mixing condition of marine and hydrothermal waters. The temperatures of mineralization by the sulfur isotopic composition coexisting pyrite-pyrrhotite from Yeonhwa No.1, sphalerite-galena from Weolam and Dong-jeom of Yeonhwa No.1 mine, sphalerite-galena and pyrite-galena from Janggun mine were $273^{\circ}C$, $460{\sim}511^{\circ}C$, $561{\sim}690^{\circ}C$, $341^{\circ}C$ and $375^{\circ}C$, respectively.

• 한국지형학회지
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• 제19권4호
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• pp.97-108
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• 2012

해안분지, 용화산과 간동분지를 포함한 강원도 동부 DMZ지역은 다양한 지형 지질학적 자원을 이용한 지속가능한 관광의 조건을 갖추고 있다. 이 지역의 지오투어리즘이 정착되기 위해서는 접근성이 부족한 산간지역 특성에 적합한 지오투어리즘을 모델이 필수적으로 필요하다. 해안분지 주변으로 용늪과 심적습지 등의 다양한 지형 경관자원이 인접하여 있으므로 이를 기반으로 인접한 지오사이트 등을 연결하여 지오투어리즘에 활용할 수 있게 하는 전략적 접근이 필요할 것으로 판단된다. 지질공원의 지정 목적에 부합하는 이 지역의 가치는 편마암과 분지내의 흑운모화강암의 특성을 비교하여 설명할 수 있으며, 또한 화강암 산지 내에서 용화산의 정상부는 돔형의 암산이며 또한 심층풍화된 지형을 절리계의 밀도 차이나 단층선 등 구조적 요인에 따른 차별적 풍화로 설명할 수 있다. 이를 통해 한반도에 발달한 대부분의 침식분지의 발달과정을 설명할 수 있는 가치가 있다.

• 한국지형학회지
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• 제25권2호
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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.

• 한국환경과학회지
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• 제6권5호
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• pp.489-496
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• 1997

The arm of this study is to determine harmful radioactive gas($Rn^{222}$)-concentrations in soils and to suggest the anormalous regions of $Rn^{222}$-concentration in Taejeon area. The range of $Rn^{222}$-concentration in the soils (45 samples) of the survey area is 100 to 2, 475 (pCi/L) and mean$\pm$$\sigma$ of those values is 489$\pm$ 505 (pCi/L). The 2% (4 samples) of soil-gas samples (45 ones) collected In the survey area is corresponded to high rusk level, 53% (24 samples) to medium one and 43% (19 samples) to low one. Especially. The $Rn^{222}$-concentration is relatively higher in schistose granite region than in other rock Mts (two-mica granite and biotite ganite) in the survey area. The $Rn^{222}$-concentration is propotional to the uranium contents in the soils. The soil hardness among the various factors is correlative with $Rn^{222}$-concentrations. To prevent the damage from $Rn^{222}$-concentrations, It is necessary to close the cracks of underground structure and to consider methods reducing $Rn^{222}$-concentration for the anormalous regions.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.344-347
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• 2005

The purpose of the study for the development of the technologies of water quality monitoring and contamination protection at water resource aquifer is to secure the groundwater as potable water resources. The results of water analysis as a basis of potable water criteria showed that 30 groundwater samples among 138 samples of small water supply system (21.7%) were exceeded the water criteria. The concentrations of Cl, $NO_3$ and Na for granite area are higher than those of gneiss and metasedimentary rocks of Ogcheon belt area and they are caused by the high vulnerability of groundwater at granite region where the residential area and cultivated land are concentrated. The spatial distribution of components indicated the close relationships between water quality and geology, land use, and topography. The multivariate statistical results showed that the water samples are divided into three groups by geology.

• 보존과학연구
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• 통권13호
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• pp.14-36
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• 1992

The investigation has been made on the rocks consisting the pagoda(12), Buddhist Statues(9) Buldaejwa and cakra(2, rewpectively), stele(5), and Flagpole wupport and stupa(6) which are stood in Weonju city, Weonju-gun, Hwoengseong-gun and Hongcheon-gun, Kangweondo. These rock-monuments range mostly in age from late Shilla Kingdom to middle Korye Kingdom. The geology around this region is mainly composed of Precambrian metamorphic rocks and mesozoic granitic rocks. The granitic rocks are largely divided into Jurassic and cretaceous ones which are slightly different in rock phase. The main rock phase consisting the monumentsare are coarse biotite granite with minor amount of hornblende in Jurassic age. Variation in rock phase is abserved even in part of the stone used in the monuments. Inclusions composed of biotite and hornblende, porphyritic texture with microcline phenocryst, igneous lineation and exfoliation according to weathering are observable in all rocks in these monuments. In the case of stele whose a body and a capstone is remained, one is composed of black slate and the other white limestone. But the turtle shaped pedestal is constituted of coarse biotite granite. These stone-monuments are strongly weathered and exfoliated out about 1∼2mm.In case of exfoliated weathering along igneous lineation, some are taken off about 3∼5mm thick. In some monuments, the degree of weathering is somewhat different according to position, grade of sculpture, and biological activity.

• Geomechanics and Engineering
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• 제25권2호
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• pp.99-109
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• 2021

Tunnel provide faster, safer and convenient way of transportation for different objects. The region where it is construction and surrounding medium has significant influence on the overall stability and performance of tunnel. The present simulation has been carried out in order to understand the behaviour of rock tunnel under static loading condition. The present numerical model has been validated with the laboratory scaled model and field data of underground tunnels. Both lined and unlined tunnels have been considered in this paper. Finite element technique has been considered for the simulation of static loading effect on tunnel through Abaqus/Standard. The Mohr-Coulomb material model has been considered to simulate elastoplastic nonlinear behaviour of different rock types, i.e., Basalt, Granite and Quartzite. The four different stages of rock weathering are classified as fresh, slightly, moderately, and highly weathered in case of each rock type. Moreover, extremely weathered stage has been considered in case of Quartzite rock. It has been concluded that weathering of rock and overburden depth has great influence on the tunnel stability. However, by considering a particular weathering stage of rock for each rock type shows varying patterns of deformations in tunnel.

• 한국산림과학회지
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• 제79권4호
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• pp.367-375
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• 1990

모암(母岩), 유기물(有機物), calcium 및 Iron oxide가 토양입단화(土壤粒團化)에 미치는 영향을 규명하기 위하여 석탄암(石炭岩), 화강암(花岡岩), 화강편마암(花崗片麻岩)을 모암(母岩)으로 하는 지역(地域)을 조사지(調査地)로 설정(設定)하고 조사지별(調査地別)로 삼림식생상태(森休植生狀態)에 따라 토양내(土壤內) 유기물(有機物), Calcium 및 Iron oxide의 함량(含量)차이가 입단안정도(粒團安定度)에 미치는 영향을 분석(分析) 평가(平價)하였다. 입단화도(粒團化度)와 관련된 요인(要因)들과 그 특성(特性) 및 침식(浸蝕)에 대한 안정성(安定性)과 밀접한 관련이 있는 입단직경(粒團直徑)을 분석(分析), 평가(平價)한 결과는 다음과 같았다. 모암(母岩)이 입단화(粒團化)에 미치는 영향(影響)을 보면 석탄암토양(石炭岩土壤)의 입단화도(粒團化度)가 21%로 가장 높았고 다음이 화강암토양(花崗岩土壤)으로 19.8%, 화강편마암토양(花崗片麻岩土壤)이 9.9%로 가장 낮았다. 입단화도(粒團化度)에 가장 큰 영향(影響)을 미치는 요인(要因)은 유기물함량(有機物含量)으로 유기물함량(有機物含量)이 증가(增加)함에 따라 입단화도 직선적(直線的)으로 증가(增加)하는 정(正)의 상관(相關)을 나타냈으며, 그 관계는 Y=4.31X-4.37 (Y : 입단화도(粒團化度), X : 유기물함량(有機物含量))과 같았다. 임상별(林相別) 입단화도(粒團化度)는 관엽수림지역(關葉樹林地域)의 토양이 침엽수림지역(針葉樹林地域)의 것보다 높게 나타났으며, 이것은 유기물함량(有機物含量)에 기인(基因)하는 것으로 인정(認定)되며 모암별(母岩別) 입단직경급(粒團直徑級)의 분포(分布)는 석탄암토양(石炭岩土壤)에서는 큰 직경급(直徑級) (0.5mm 이상) 입단(粒團)의 비율(比率)이 높은 반면 화강편마암토양(花崗片麻岩土壤)에서는 작은 직경급(直徑級) (0.25mm) 입단(粒團)의 비율(比率)이 높았고 화강암토양(花崗岩土壤)에서는 0.5mm직경급입단(直徑級粒團)을 중심으로 정규분포(正規分布)하는 경향(傾向)을 나타냈다. 토양(土壤)중 Ca과 Fe의 함량(含量)이 입단화도(粒團化度) 미치는 영향(影響)은 부분적(部分的)으로만 인정(認定)되고 있으나 석탄암지역(石炭岩地域)에서는 Ca의 영향(影響)이 유기물(有機物)과 함께 입단화(粒團化)에 크게 기여(奇與)하는 것으로 나타났다.