• 자원환경지질
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• 제42권1호
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• pp.9-25
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• 2009

충주지역 북서부 옥천변성대는 문주리층, 대향산규암, 향산리돌로마이트, 계명산층이 분포하고 있으며 현재까지 층서적 관계가 논란이 되고 있는 지역이다. 충주지역에 분포하는 북서부 옥천변성대에 대한 층서적 연구를 위해 충주호일대에 두 지점의 노두를 선정하여 단면에 대한 정밀기재 및 인근지역에 대한 야외조사를 실시하였다 문주리층과 대향산규암의 경계는 정이적인 변화가 인지되나 경계부는 층리면과 평행한 단층이 발달한다 대향산규암과 향산리돌로마이트는 정합적인 것으로 판단된다. 향산리돌로마이트와 계명산층은 단층을 경계로 접하고 있다. 연구지역의 북부에는 $41^{\circ}/280^{\circ}$의 습곡축을 가지는 습곡이 분포하는 것이 확인되었으며, 두 층의 경계에 발달하는 단층은 충상단층일 가능성도 있으나 습곡이 형성되는 동안 나타나는 단층일 가능성도 있다. 본 연구에서 확인된 점이적인 암상변화와 기존 연구 결과를 볼 때 경계부의 단층은 습곡이 형성되는 동안 층리면과 평행하게 발달하는 단층으로 판단된다 향산리돌로마이트와 계명산층의 경계부에 발달하는 단층은 층리면과 평행하게 발달하며, 돌로마이트가 반복적으로 나타나고 있는 점을 볼 때 충상단층으로 판단된다. 두 층이 충상단층 관계일 경우 상부의 계명산층이 문주리층 아래에 놓이게 된다. 하지만 계명산층과 문주리층은 비슷한 암상분포를 보이며, 신원생대의 절대연령을 나타내는 점을 볼 때 두 층이 동일한 층일 가능성이 있을 것으로 생각되며 충상단층에 의해 반복적으로 분포하는 것으로 판단된다. 이러한 결과를 종합해 볼 때 충주지역 북서부 옥천변성대의 층서는 하부로부터 계명산층/문주리층, 대향산규암, 향산리돌로마이트의 정합적 관계로 판단된다.

• 동굴
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• 제4호
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• pp.41-50
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• 1996

The coastal plains of the Puna and Ka' u Districts of the island of Hawaii are a contradiction to the popular view that the island of Hawaii is a tropical rain forest or a vegetated landscape with abundant water sour This section of the island lies in the rain shadow of Mauna Loa a Kilauea Volcanoes and receives less than 30 inches of annual precipita When rain does come. it is in the form of sudden down pours. givi residents of the area little time to collect and conserve water. Due to porous nature of the rock. there is no standing surface water. In spite of these harsh climatic conditions. archeological evidence indic that an extensive agriculture complex existed not only along the coast. into the most remote parts of what is called the Ka'u Desert. Pass through these agricultural areas are historic and pre - historic t systems. These trail systems apparently played a significant suppor role for exchange between the ahupua's (classic land divisions of Haw and the geopolitical districts. The question arises as to how could vast agricultural complexes a heavy foot travel over miles of arid land exist without dependable wa sources\ulcorner While planting - pits and mounds were designed to make most efficient use of available water and conserve moisture(Carter 19 9). people involved in planting also needed potable water for surv Most publications and research papers dealing with the early population this area make only oblique reference to springs and wells which t populations depended upon. The Federal Cave Resource Protection Act(1988) has served as imprtus for the National Park Service to look closer at the lava tu caves and fault cracks within Hawaii Volcanoes National Park. P visitors to these underground areas found large volumes of standing wa in fault cracks. and abundant drip areas with the lava tubes. Re observes noted that in most cases. where the cracks and caves we located in the arid sections of the park. there has been extens modifiacation or utilization of these water sources by the early Hawaii and others. The variety of western containers used for collection indica that these water sources were used during historic times. William E described similar water sources in his narrative of his trip around island in 1823(Eills 1979), This report is directed at documenting recent observations and a stimulating further research into early Hawaiian water collection syst It also explores the implications that power and political influence of e chiefs in the arid portions of Hawaii could have been linked to the con of the water resources.

• 자원환경지질
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• 제22권2호
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• pp.91-102
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• 1989

The gravity measurement has been conducted at 61 stations with an interval of about 500 to 1,000 m along two survey lines of about 47 Km between $Chungju-Jech{\check{o}}n$ and $Salmi-D{\check{o}}cksanmy{\check{o}}n$ in order to study on the subsurface geologic structure and structural relation between $Okch{\check{o}}n$ Group and Great Limestone Group of $Chos{\check{o}}n$ Supergroup. The Bouger gravity anomalies were obtained from the reduction of the field observations, and the distribution patterns of the basement and subsurface geologic structure were interpreted by means of the Fourier-Series and Talwani method for two-dimensional body. The depth of Conrad discontinuity varies from 12.7 Km to 15.7 Km, and vertical displacements along the Osanri and Bonghwajae faults are 1.0 Km and 1.5 Km, respectively between Chungju and $Jech{\check{o}}n$. The depth of Conrad discontinuity varies from 13.8 Km to 15.4 Km, and vertical displacement along the Bonghwajae fault is 0.5 Km between Salmi and $D{\check{o}}cksanmyon$. The basement is widely exposed at several places between Chungju and $Jech{\check{o}}n$. In the unexposed area between Osanri and $W{\check{o}}lgulri$, its depth is from 1.5 Km to 2.1 Km. It is displaced downward along the Osanri and Bonghwajae faults by 0.8 Km and 0.6 Km, respectively, and is displaced upward along the Dangdusan fault by 1.6 Km. On the other hand, the depth of the basement varies abruptly by the Sindangri, Jungwon, Kounri, and Bonghwajae faults between Salmi and $D{\check{o}}cksanmy{\check{o}}n$, and it is from 2.8 Km to 3.2 Km around $Salmimy{\check{o}}n$, from 1.6 Km to 2.5 Km between the Sindangri and Bonghwajae faults, 3.0 Km near Koburangjae, and 2.5 Km at $Doj{\check{o}}nri$. The high Bouguer gravity anomalies are due to the accumulation of $Okch{\check{o}}n$ Group and $Jangs{\check{o}}nri$ Metamorphic Complex whose density is higher than the basement exposed between Sondong and Osanri, and imply the existance of Bonghwajae Metabasite or hornblende gabbro of high density distributed along the Bonghwajae fault in the vicinity of Koburangjae. The low Bouguer gravity anomalies resulted form the fracture zone associated with fault or rock of low density imply the existance of the Osanri, Bonghwajae, Dangdusan faults and $Daed{\check{o}}cksan$ thrust between Chungju and $Jech{\check{o}}n$, the uplift of the basement by the Sindangri, Jungwon, Kounri, and Bonghwajae faults, and extensive distribution of Cretaceous biotite granites between Salmi and $Docksanmy{\check{o}}n$. The thickness of $Okch{\check{o}}n$ metasediments varies from 1.5 Km to 3.2 Km, and that of Great Limestone Group of $Chos{\check{o}}n$ Supergroup from 200 m to 700 m. It is interpreted that $Okch{\check{o}}n$ Group is in contact with Great Limestone Group of $Chos{\check{o}}n$ Supergroup by the fault zones of the Bonghwajae and $Daed{\check{o}}cksan$ faults, and the Bongwhajae fault is a thrust of high angle, by which the east of the basement is displaced downward 0.5 Km between Chungju and lechon, and 1.0 Km between Salmi and $D{\check{o}}cksanmy{\check{o}}n$.

• 지구물리
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• 제3권1호
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• pp.57-66
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• 2000

울산단층의 구조와 위치는 한반도 동남부의 지각 진화 해석에 중요한 역할을 한다. 울산단층을 피복하고 있는 충적층의 두께와 충적층 하부의 단층 수반 파쇄대를 조사하고 가능하다면 주단층의 정확한 위치를 파악하기 위하여 굴절법 탄성파탐사와 쌍극자 전기비저항탐사를 수행하고 분석하였으며, 이들 결과와 함께 이 지역에서 독립적으로 수행된 타연구의 반사법 탄성파탐사 결과를 도입하여 종합적인 해석을 하였다. 전기비저항탐사에서 동천 동쪽에서의 탐사선에서는 단층으로 사료되는 비저항 이상대가 발견되지 않았으나, 동천 서족 탐사선에는 잘 발달된 연속적인 낮은 비저항이상대를 발견하였다. 이는 울산단층의 주단층은 동천이나 동천 서쪽에 위치하는 것을 시사한다. 동천 동쪽 탐사선에서 실시한 굴절법 탄성파탐사에서는 기반암과 충적층의 경계 및 지하수면으로 사료되는 두 굴절면을 발견하였으며, 충적층의 두께는 약 30 m정도로 해석되었다. 결과해석의 신뢰도를 높이기 위하여 본 조사와 별도로 실시된 반사법 탄성파 자료를 참고한 결과 반사법 탄성파 탐사에서 발견된 많은 단층대가 굴절법탐사나 비저항탐사에서는 나타나지 않았다. 낮은 비저항 이상은 파쇄대를 따른 함수량의 영향보다는 점토의 영향에 밀접한 관련이 있는 것으로 가정할 때 고원인은 설명되나, 굴절법탐사나 비저항탐사의 해상도와 관련이 있을 수 있다. 정확한 원인구명을 위해서는 정밀한 연구가 필요하다. 일반적으로 전기비저항 탐사는 단층위치 파악에 유용한 지구물리학적 탐사법으로 알려져 있으나 본 조사에서는 반사법 탄성파 탐사에 비해 그 효과가 뚜렷하지 못하였다. 쌍극자 전기비저항탐사에서 해상도를 유지하면서 가탐심도를 증가시키기 위해서는 전개수를 늘려야 한다. 그러나 배경잡음 때문에 한계점을 가지는데, 본 조사에서 측정치의 통계학적 성질을 볼 때 조사지역에서의 측정치가 전개수 16까지는 충분한 의미를 가짐을 알 수 있었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1502-1508
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• 2011

Ground anchor expands the hollow wall of settled part and has the structure which resists the designed tensile load by the bearing pressure generated by the wedge of the anchor body pressing in the expanded part. Such ground anchor has been recognized for stability and economicality since 1960s in technologically advanced nations such as Japan and Europe, and in 1970s, the Japan Society of Soil Engineering has established and announced the anchor concept map. The ground anchor introduced in Korea, however, has the structural problem where the tensile strength is comes only from the ground frictional force due to expansion of the wedge body. In an interval where the ground strength is locally reduced due to fault, discontinuation or such, this is pointed out as a critical weakness where the anchor body of around 1.0m must resist the tensile load. Also, in the installation of concrete block, the concentrated stress of concrete block constructed on the uneven rock surface causes damage, and many such issues in the anchor head have been reported. Thus, in this study, by using the expanded bit for precise expansion of settled part, the ground anchor system was completed so that the bearing pressure of ground anchor can be expressed as much as possible, and the bearing plate was inserted into the ground to resolve the existing issues of concrete block. Through numerical analysis and pullout test executed for verification of site applicability, the pullout-behavior characteristics of anchor was analyzed.

• 화약ㆍ발파
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• 제28권1호
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• pp.71-75
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• 2010

한일해저터널 구상에 이어 한중해저터널에 관한 토론이 공개적으로 시작되었다. 이에 우리 기술진의 현재의 역량과 정치적 경제적 협조방안을 열거하였으며 특히 해저터널 건설시의 기술적 문제점과 해결과제를 조사 연구하였고 이에 따른 방안을 제시하였다. 굴착기술 측면에서는 깊은해저에서의 단층대 등 암반상태를 감안한 발파 방수처리기술 등을 고려 해야겠다. 완공 후 터널내 화재와 누수관리 등에 더욱 유의하여 설계 시공하고 고급 건설사업관리제도(CMP)와 가치공학 및 창조경영공학(CVS)등을 적용해야 할 것으로 생각된다.

• 화약ㆍ발파
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• 제31권2호
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• pp.40-49
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• 2013

터널 막장전방의 지반조건을 예측하는데 굴절법 탄성파탐사가 주를 이루어 왔으나, 최근에는 탄성파탐사 기기 및 기법의 발전에 힘입어 시추공을 이용한 토모그래피 등이 활발히 적용되고 있다. 본 논문은 TSP (Tunnel Seismic Prediction) 탐사장비를 이용하여 막장전방의 지반조건을 예측함으로써 암질 변화구간이나 단층, 파쇄대등 지질이상대를 파악하여 터널 굴착 시 시공 및 안정상의 문제점을 예방하는데 목적이 있다. 본 연구에서는 ${\bigcirc}{\bigcirc}$-${\bigcirc}{\bigcirc}$ 도로개설현장에서 적용된 TSP탐사에 의한 터널전방의 지질이상대를 파악한 사례로 막장탐사 방법의 타당성을 살펴보고자 하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.140-153
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• 2005

During the tunnel construction the major failure mode can be categorized as: tunnel failure just after the tunnel excavation without support, failure after application of shotcrete and finally failure after setting the concrete lining. The failure mode just after the tunnel excavation without support, can be further classified as : bench failure, crown failure, face failure, full face failure, failure due to weak strata and failure due to overburden. Moreover the failure after application of shotcrete is classified as heading face failure, settlement of shotcrete support, local failure of shotcrete lining and invert shotcrete. To find out the major causes of tunnel collapse, the investigation was done in case of the second phase of Seoul subway construction. The investigation results depicted that the major causes of tunnel collapse were due to the weak layer of rock/fault and sudden influx of ground water from the tunnel crown. While the investigation results of the mountain road tunnels construction have shown that the major causes of tunnel failure were inadequate analysis of tunnel face mapping results, intersection of faults and limestone cavities. In this paper some recent measurement in order to mitigate such tunnel collapse are presented

• 자원환경지질
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• 제23권1호
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• pp.59-71
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• 1990

Magnetic anisotropy of a total of 213 independently oriented Tertiary rock samples from Pohang-Ulsan area has been studied. The sampled strata comprise basalts, tuffs and black shale, and range in age from Eocene to Miocene. The previous palaeomagnetic studies indicate that their magnetic carrier minerals are titanomagnetites. Among 23 sampled sites, 11 sites were found to preserve magnetic load foliation parallel to the bedding plane caused by the Iithostatic load of the overlying strata. Other 4 sites showed magnetic lineation indicating the flow direction of lava and tuffs. The remaining 8 sites revealed the magnetic tectonic foliation nearly vertical to the bedding plane. This magnetic foliation is interpreted to be generated by tectonic compression which acted nearly horizontally during the solidification stage of the strata. The compression directions deduced from the tectonic foliation of the 8 sites can be grouped into internally very consistent two group: a N-S trending one and the other WNW-ESE trending one. It is interpreted that the former N-S compression was associated with the N-S spreading of the East Sea(Sea of Japan) and the dextral strike-slip movement of the Yangsan-Ulsan fault system. The latter WNW-ESE compression is interpreted to represent the folding and reverse faulting activity in the Korean and Tsushima straits during middle/late Miocene times.

• 자원환경지질
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• 제29권2호
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• pp.119-127
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• 1996

Electrum-sulfide minerals of the Namsan Au-Ag mine were deposited in two stages of quartz and calcite veins that fill fault planes in Mesozoic granitic rocks (230~155 Ma). The K/Ar radiometric dating of hydrothermal sericite indicates that mineralization is early Cretaceous age ($127{\pm}3.0Ma$). Mineralogic, fluid inclusion and sulfur isotopic data show that ore minerals were deposited at temperatures between $340^{\circ}C$ and $200^{\circ}C$ from fluid with salinities of 3 to 6 equiv. wt % NaCl. Evidence of fluid boiling (and $CO_2$ effervescence) indicates a maximum pressures of 100 bars. The formation temperature and $fs_2$, of Au-mineralization from the Namsan mines are mainly $280{\sim}230^{\circ}C$ and $10^{-11}{\sim}10^{-13}$ atm, respectively. Au deposition was likely a result of boiling caused to chemical change (pH, $f_{O2}$, ${\Sigma}_{H_2S{\cdot}{\cdot}}$) of ore-fluids. Sulfur isotope composition of sulfide minerals (${\delta}^{34}S=5.1$ to 8.2‰) are consistent with ${\delta}^{34}S_{{\Sigma}{H2S}}$ value of +6 to +7‰, suggesting an igneous source of sulfur partially mixed with wall-rock sulfur.