• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1053-1059
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• 2009

In this study, slope hazards mitigation methods for a natural terrain are systematically classified to survey the mitigation methods and develop a data base system. Also, field survey sheets which can be recorded the features of mitigation methods installed in the natural slope are developed. The slope hazards mitigation methods in the natural slope are classified as hillside part method and valley part method. The slope part sheet and the valley part sheet are also drawn up for field survey. As the result of the filed survey of mitigation methods about 50 points in Muju and Jangsu area, grass painting and slope covering methods are dominant in case of slopes part. In case of valley part, slit dam, concrete check dam and slope foot barrier are applied simultaneously.

• The Journal of the Petrological Society of Korea
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• v.23 no.2
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• pp.145-152
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• 2014

Geological heritages can be defined conveniently as geological records worthy of conservation, and are represented in most cases by geological outcrops. So survey and evaluation of geologic outcrops are necessary for better conservation of geological heritages. As a measure to prevent potential destruction of geological heritages from various development projects, I propose construction of database based on survey and evaluation forms of geological outcrop, which can also be used for environmental impact assessment. The geological survey form consists of survey area, category, subcategory, location, dimension, geologic features, photo, description, and investigator. The evaluation form consists of evaluation category, detailed evaluation, comprehensive evaluation, and evaluation grade. The evaluation category is divided into academic aspect, education effect and landscape. The detailed evaluation items for academic aspects and education effect are representativeness, rarity, diversity and typicality, while those for geomorphology and landscape are peculiarity, aesthetics and naturalness. The evaluation grades are divided into five, where the first grade means a must of conservation.

• Journal of the Korean earth science society
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• v.24 no.3
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• pp.172-180
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• 2003

Geologic field survey is very important for the high school students who take the courses of earth science under the 7th earth science curriculum, however actually it is very difficult for the students to survey in the field because of long time and distance, and expenses. To overcome these difficulties, this study focused on developing the web contents and teaching-learning materials for virtual geologic field survey of the Songaksan and Jisagae area, Jeju island. The developed web contents were placed into three parts; main manu, sub manu and contents to help the learners flow-chart of the program easily. To overcome the weakness of existing textual web materials, some movable images and worksheets were provided for the learners, and the web contents were designed for the learners to experience as similar as the geologic field survey may let them do.

• Journal of the Korean earth science society
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• v.26 no.1
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• pp.41-57
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• 2005

The purpose of the study is to develop a educational data in order for students to perform geologic field survey effectively by themselves. A area around the Duta Mountain is selected. which is located at the southeastern part of Eumsung sedimentary basin because various rock types and geologic structures are well shown in this area and also it is convenient to reach there. Thirteen stops for observation are chosen m a route f3r exercising field geologic investigation. Data for field research are given and described in detail from each stop for observation. To do this, students make their own route map using general or digital geographic map and aerial photo is added to know relationship between large-scale structure and different rock types regionally. Moreover, it is designed to minimize conflict factors that may be experienced from the real field survey by showing outcrop photographs and polarizing photomicrographs of rut samples related to each stop and geologic structures. The attitude of students is investigated with the data of field geologic survey for students of an Earth Science class in the College of Education in Chungbuk National University. The results indicate that the educational data for geologic field survey brought positive changes that greatly help students perform field survey in definitive side, especially formation of absolute concepts on earth science.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.231-236
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• 2002

The understanding of underground geologic structures is of great importance for the surface and subsurface constructions, prevention of natural hazards such as land-slides and subsidence, and many other areas. To get the information on the geologic conditions, many of investigations such as geologic survey, geophysical explorations, testings on the physical properties of rocks, drilling tests and logging, and groundwater surveys are usually conducted, and tremendous data are collected accordingly. In general, however, these huge amount of data are interpreted in the individual areas only. If these data are analyzed collectively, much more information on the geologic conditions can be obtained. In this study, 3D visualization of borehole logging data is attempted. Borehole logging data are obtained at the urban subsidence area. To compare the 3D logging data with other geologic and geophysical data such as resistivity tomography data, interface module was developed. The 3D visualization of logging data and the comparison with other data can be helpful for the understanding of underground geologic structures.

• Economic and Environmental Geology
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• v.28 no.1
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• pp.79-88
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• 1995

The gravity measurment has been carried out at 48 gravity stations with intervals of 1.0~1.5 km along the survey line between Samcheog, Gosari and Taebaek to study subsurface geology and geologic structure in the northeastern part of the Ockchon zone. The Bouguer gravity anomaly values were obtained from the measured gravity values through the gravity corrections. The subsurface geology and geologic structure were interpreted quantitatively by means of the Fourier series method and Talwani method for 2.5 dimensional body. In the study area, the depth of Conrad discontinuity is about 10 km at Samcheog, northeastern end of the survey line, and it is increased rapidly to about 12.5 km at Miro, 15 km at Gosari and 15.5 km at Dongjeom, southwestern end of the survey line, respectively. The depth of the basement of the Ockchon zone exposed at Samcheog is increased smoothly to about 2 km at 5 km from Samcheog along the survey line, and is exposed again in the area between Singiry and Gosari. Beyond Gosari its depth is increased to about 1.7 km, and displaced 2.3 km downward by Osipcheon fault near Dogyeri and 0.5 km by Baeksan thrust near Cheolam, respectively. Many V-shaped low Bouguer gravity anomalies resulted from the fracture zone associated with faults imply the existence of Osipcheon fault and several inferred faults. The low Bouguer gravity anomaly zone between Tongdong and Dongjeom is caused by Jurassic gneissose granite. A local high Bouguer gravity anomaly at 35 km along the survey line from Samcheog is interpreted by the effect of iron deposit of high density existed at subsurface. The thickness of Great Limestone Group varies from 0.5 km to 1.4 km, that of Pyeongan Supergroup from 0.4 km to 0.9 km, and that of Yangdeog Group is about 0.3 km. The thickness of Jurassic gneissose granite varies from 1.5 to 3.0 km.

• The Journal of Engineering Geology
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• v.16 no.1 s.47
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• pp.23-30
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• 2006

This study was carried out to understand the relationship between orientation of tecto-lineaments obtained from aero-photograph and orientation of discontinuities measured at field for the rock types of igneous, sedimentary and metamorphic rocks in Andong area. Total 847 tecto-lineaments were extracted from the aero-photographs and total 1,940 discontinuities including joints, foliations and faults were measured during geologic survey. By using the software DIPS, preferred trends of tecto-lineaments were deduced as N30E-N40E for igneous rocks and N50E-N60E for both sedimentary and metamorphic rocks, while the trends of discontinuities were found as N40E-N50E for igneous rocks, N50E-N80E for sedimentary rocks and N50E-N60E for meta morphic rocks. Even though both orientations for a given rock type showed relatively good agreement in its trend, some discrepancy is also appeared. Since construction safety of geo-structures such as tunnel and slope, etc., is significantly affected by the orientation of discontinuities in rock masses, it is highly recommended to perform a detailed geologic survey as well as an aero-photograph interpretation at a design stage.

• The Journal of Engineering Geology
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• v.27 no.4
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• pp.417-427
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• 2017

This study aims to present cases of rock slope failures caused by geological structures. Status of slope failures, results of cause analysis and stabilizing methods are introduced, focusing primarily on rock slope failures caused by specific geologic structures, such as intersection of faults infilled with clay, foliation and fault shear zone by dike intrusion and deep-seated clayey layer along lithologic boundary. Detailed geological survey, geophysical exploration and boring survey were conducted for cause analysis. Stabilizing method to prevent further slope failures and to ensure long-term stability of slopes were established, considering characteristics of geological structures, types of failure and geological conditions.

• The Journal of Engineering Research
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• v.7 no.1
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• pp.61-70
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• 2005

Conventional geological survey utilizes the manual compass for mass amount of measurements of the geologic structure. Portable multifunction digital compass system was required by more detailed geological survey, due to increasing construction for rock slopes and runnels. In this paper, the system was implemented by using Intel PXA 255 embedded board as a system controller, and was composed of tilting sensor, digital azimuth sensor, and Global Positioning System (GPS) module. After the measured location, strike, and the angle of dip with our implemented system were transmitted to Personal Digital Assistant (PDA) or notebook, these data could be used for geologic structure analysis. It is expected that the availability of cheap and improved digital compass will reduce the coast and time of geological survey extensively.

• Economic and Environmental Geology
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• v.25 no.3
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• pp.351-358
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• 1992

The gravity measurement has been conducted at 327 station with an interval of 25 m along the survey lines of 1.6 km and 1.7 km traversing Hyungsan river and of 2.35 km and 2.42 km running N-S direction near Heunghae-eup in Pohang basin. Bouguer gravity anomalies were obtained, and geologic structure along four survey lines were interpreted by applying Fourier series and Talwani methods for two demensional body. A fault is in existence along the Hyungsan river, and northern block of it is displaced down by 150 m to 200 m relative to southern one. The thicknesses of Yeonil Group vary from 250 m to 550 m and from 150 m to 300 m in the northern and southern blocks of the fault, respectively. Another fault is in existence running E-W direction near Heunghae-eup, and its southern block is displaced down by about 250 m relative to its northern block. The thicknesses of Yeonil Group vary from 200 m to 400 m and from 500 m to 700 m in the southern and northern blocks of the fault, respectively. Above two faults are normal faults and make a graben structure, which results the age of rocks in the central region between the faults is younger than those of outside regions. This result coincides with that of paleontological study.