• Geophysics and Geophysical Exploration
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• v.22 no.3
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• pp.149-159
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• 2019

Borehole elemental concentration logging, measuring neutron-induced gamma rays by inelastic scattering and neutron capture interactions between neutron and formation, delivers concentrations of the most common elements found in the minerals and fluids of subsurface formation. X-ray diffraction and X-ray fluorescence analysis from core samples are traditionally used to understand formation composition and mineralogy, but it represents only part of formations. Additionally, it is difficult to obtain elemental analysis over the whole intervals because of poor core recovery zones such as fractures or sand layers mainly responsible for groundwater flow. The development of borehole technique for in situ elemental analysis plays a key role in assessing subsurface environment. Although this technology has advanced consistently starting from conventional and unconventional resources evaluation, it has been considered as exclusive techniques of some major service company. As regards domestic research and development, it has still remained an unexplored field because of some barriers such as the deficiency of detailed information on tools and calibration facility for chemistry and mineralogy database. This article reviews the basic theory of spectroscopy measurements, system configuration, calibration facility, and current status. In addition, this article introduces the domestic researches and self-development status on borehole elemental concentration tools.

• Journal of the Korean Geotechnical Society
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• v.33 no.11
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• pp.83-95
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• 2017

This study examined the magnitude and distribution of earth pressure on the excavation wall in jointed rock mass by considering different groundwater conditions under various rock types, joint inclination angles, and earth pressure coefficients. Based on a physical model test (Son and Park, 2014), extended studies were conducted considering rock-structure interactions based on the discrete element method, which can consider the joints characteristics of rock mass. The results showed that the earth pressure was highly influenced by the groundwater condition as well as the rock type, joint inclination angle, and earth pressure coefficient. The results were also compared with Peck's earth pressure for soil ground, and clearly showed that the earth pressure in jointed rock mass can be greatly different from that in soil ground.

• The Journal of the Petrological Society of Korea
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• v.23 no.4
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• pp.367-373
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• 2014

Yeongsan-eupseong is located at Seongnae-ri, Yeongsan-myeon, Changnyeong-gun, Korea. We investigated the petrological features of the stone materials used for the rampart, and estimated their provenances. The stone materials consist of andesitic rocks, granitic rocks and sedimentary rocks. In the preserved rampart the andesitic rocks are relatively abundant, whereas the large number of granitic rocks are used for restoration. Chaeyaksan andesite and Chusan andesite are thought to be the source for the andesitic rocks. The original granitic rocks are of granite porphyry, and are likely to have been delivered from the near granite porphyry outcrops. On the other hand the granitic rocks used for restoration are classified to be biotite granite. The sedimentary rocks show thermally metamorphosed feature and changed to hornfels. The source for the hornfels is the contact area between the sedimentary rocks and granitic rocks near the Yeongsan-eupseong.

• Economic and Environmental Geology
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• v.37 no.4
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• pp.391-400
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• 2004

The purpose of this study is to analyze the geothermal anomaly based on the relationship between heat flow values and geologic settings in South Korea. For this, a total of 247 heat flow data was constructed to spatial database and the spatial database was overlaid with 1 : 1,000,000-scale digital geologic map using GIS. As the result, the average of heat flow is 64$\pm$14mW$m^{-2}$in South Korea. In the lithological aspect, the area of sedimentary rock shows high heat flow of 74mW$m^{-2}$, sedimentary/volcanic rock area 62mW$m^{-2}$, plutonic rock area 63mW$m^{-2}$ and metamorphic rock area 61mW$m^{-2}$. In the geologic time sequence, the Cenozoic strata has 91mW$m^{-2}$, the Mesozoic and Paleozoic strata 65mW$m^{-2}$, the Proterozoic strata 55mW$m^{-2}$ and the Archean strata 61mW$m^{-2}$.

• Tunnel and Underground Space
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• v.10 no.2
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• pp.211-217
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• 2000

In this, study, some laboratory tests and in-situ test were performed for Taegu area. Test blasting was conducted to determine blasting vibration coefficients. The uniaxial strength of rocks vary widely from weathered rock to extremely hard rock. Boasting vibration coefficient, K and n were 114.8, 1.48 for Sungseu site, where rocks show weathered to medium strength.

• Journal of Korean Elementary Science Education
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• v.24 no.5
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• pp.546-557
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• 2005

The purpose of this study was to analyze the characteristics of the geology-related contents in the 1st~7th elementary science curriculum. Our analysis was based on the analytical frameworks of geology-related contents (the structure of the contents, the amount of teaming, the contents of the experimental activities, the transitions of the terminology, and the change in the number of illustrations). The results are as follows: 1. Consistently covered contents were limited to weathering of the rock and soil, igneous rock, sedimentary rock, metamorphic rock, and the change of the earth's, fold and fault, earthquake and volcano, geologic stratum and fossil. 2. The geological contents account for (average), 11.5% (maximum), and 5.1% (minimum) of the elementary science curriculum. Most contents covered in the curriculum were rock and soil, and the change of the earth's surface. 3. Continuously covered experimental contents were the weathering and soil, igneous rock, change of the earth's surface, geologic stratum and fossil. 4. The terminology on the rock was the most frequently changed. Whenever the curriculum changed, the addition, deletion, or renaming of terminology led to confusions. 5. In terms of the transition of illustrations, the pictures replaced the figures or diagrams as the representative illustration methods as the science or the textbook compilation skill develope. The cartoons or tables were also used increasingly in order to help the children to understand and pay attention to study.

• Proceedings of the KSEG Conference
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• 2004.03a
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• pp.25001-25035
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• 2004

석재의 무분별한 개발로 인한 산림훼손을 최소화하고 상품성 있는 석재 가능성을 확인하기 위하여 채석허가 이전에 지질조사 및 시추탐사를 통한 매장량과 경제성 등 채석타당성을 평가하는 것이 필요하다. 골재가 부존하는 충적층은 다양한 입도와 지층 단면을 가지고 있기 때문에 이를 대상으로 골재를 채취하려면 골재의 품질과 매장량을 확인해야 한다. 또한 무분별한 골재 채취는 홍수시 유량과 유속을 변경시키므로 합리적인 채취량을 추산할 필요가 있다. (중략)

• 한국해양학회지
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• v.13 no.1
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• pp.1-8
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• 1978

A seismic reflection Survey was carried out in the offshere area between Geoje Island and Namhae Island, utilizing the echosounder with the frequency 28KHz and thd Uniboom with the filter band 800∼2000Hz. The results show the submarine topography, sedimentary layer structure and the depth distribution of the base rock. The water depth of the sea in the survey area is less than 80m; up to 40m contour line the sea bottom surface has a slight dip(about 1/1000), while in the zone deeper than 40m the bottom topography has a irregular relief. The thickness of the whole sedimentary deposit is about 20∼70m and divided into 3 layers: Upper layer(A layer) with horizontal laminae, intermediate layer(B layer) with cross-bedding and groove structure, and lower layer(C layer) not showing any sedimentary structure on the seismic reflection profile. The surface of the base rock is deeper gradually in the south-eastern part of the survey area and extends to 140m depth. The vertical sediments sequences, composed of B layer and A layer, show the type of transgressive sequences. It is interpreted that B layer was formed at one period when the sea level was lower 40∼60 than the present and ince then, following the rising of the sea level, A layer was deposited.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.52-52
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• 2010

동해 한국대지 남부(south Korea Plateau)에서 2010년 2월에 한국해양연구원의 온누리호를 이용하여 해저지형 및 자생광물 탐사가 실시되었다. 다중빔 음향측심기를 이용한 해저지형 조사는 2-3 km 탐사측선 간격으로 약 400 L-km 정도가 실시되었다. 조사구역 A($37^{\circ}$ 16'-18'N, $130^{\circ}$ 02'-16'E)는 890-1,900 m의 수심범위와 남쪽으로 갈수록 수심이 깊어져 울릉분지(Ulleung Basin)와 연결된다. 크고 작은 소규모의 구릉이 사면을 따라 다수 분포하고 있다. 조사구역 B($37^{\circ}$ 26'-40'N, $130^{\circ}$ 23'-34'E)의 정상부는 900-1,000 m로 비교적 평평하게 나타났고, 남동방향으로는 2,200 m까지 급격하게 수심이 증가하는 사면으로 이루어져 있다. 한국대지내 노출 암반지역은 남동쪽 사면의 일부 지역에 분포하고 있다. 자생광물 탐사는 일차적으로 천부지층 탄성파탐사를 수행하여 시료채취 가능 여부를 현장에서 확인한 후에, A 및 B구역내 11개 지점에서 드렛지를 이용하여 암석시료를 채취하였다. 채취된 암석은 주로 현무암이며, 많은 양의 화산기원 부석(pumice) 및 화산재(box core 자료)도 확인되었다. 또한, 인광석으로 추정되는 암석과, 망간단괴(manganese nodules)와 망간각(manganese crust)의 일부 시료도 채취하는데 성과가 있었다.

• Journal of the Korean earth science society
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• v.24 no.3
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• pp.128-134
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• 2003

This study is focused on how much middle school students who study the chapter of first-grade science,'The Material and Change of the Earth's Crust', connect and understand what they learn with their environment and surroundings. This paper will discuss the connection between school education and living surroundings and how much the difference between the surroundings influences students' concepts and attitudes toward science. This study included 330students in the second year of middle schools from Jeonju, Buan and Jinan in Jeollabuk-do. This study analyzed students' concepts of mineral and rocks by having them observe samples in class. Only 16 percent of the students observe surrounding rocks with interest, but most of them are not interested. Chaesukgang and Mountain Mai are two local places in Jeollabuk-do which have a lot of specific stratum and geological structures, so it's easy for teachers to provide an outdoor experience by showing the students rocks and geological structures. Although which students have a little more observation experience than Jeonju area students, students who throughout the county seldom do outdoor observation learning. By collecting and observing the surrounding minerals and rocks, along with teaching the chapter 'The Materials and Change of the Earth's Crust', and by visiting outdoor locations while teaching about geological structures, we can improve our teaching.