• Tunnel and Underground Space
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• v.31 no.3
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• pp.145-166
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• 2021

Korea Stress Map database is built by integrating actual data of 1,400 in-situ stress measurements using hydraulic fracturing and overcoring method in South Korea. Korea Stress Map 2020 is presented based on the guideline proposed by World Stress Map Project. As detailed data, stress ratio and maximum horizontal stress direction distribution for each region are also presented. The dominant maximum horizontal stress direction in the Korean Peninsula is from northeast to southeast, and the magnitude of the in-situ stress is relatively distributed. There is some stress heterogeneity caused by local characteristics such as topographical and geological properties. We investigated case studies in which the in-situ stress was affected by mountainous topography, difference in rock quality of fracture zone, presence of mine or underground cavities, and geological structure of fault zone.

• Journal of The Geomorphological Association of Korea
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• v.20 no.1
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• pp.35-43
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• 2013

This study is intended to provide resources of on-the-spot experience learning activities for students by investigating characteristics of geomorphological and geological landscapes in Sado(including Jungdo and Jeungdo). There are nine types of geomorphological and geological landscape according to the classification from NIER(National Institute of Environmental Research) or seventeen types of it, according to the categorization from KEI(Korea Environment Institute). Such geomorphological and geological landscapes are useful as a place for on-the-spot learning activities that various types of geographical and geological features suggested in the elementary and middle school textbooks and also as a basic data for ecotourism and geotourism for visitors in Sado. In addition, specific targets to be investigated for geographical and geological heritage suggested by KEI should be determined in terms of conservation value through professional and thorough field investigation.

• The Journal of Engineering Geology
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• v.26 no.3
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• pp.339-352
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• 2016

The best way of investigating the physical and mechanical properties of subsurface materials is the combined interpretation of data from borehole geophysical surveys and geotechnical experiments with rock samples. In this study two surface seismic surveys with refraction and surface-wave method are alternatively conducted for downhole seismic surveys in test site for geological field trip in Jeungpyung, Chungbuk. P- and S-wave velocity structures are delineated by refraction and MASW (multichannel analysis of shear waves) methods, respectively. Possion's ratio section, reconstructed from P- and S-wave velocities, is correlated to the outcrop geological features consisting of reddish sedimentary rock, gray volcanic rock, and joints/fractures. In addition, rock samples representative for reddish sedimentary and gray volcanic features are geotechnically analyzed to provide physical, mechanical properties, and elastic modulus. Dynamic elastic moduli estimated from geophysical data is found to be higher than the one from geotechnical data. Reddish sedimentary rock characterized with low porosity and moisture content corresponds to the zone of low electrical resistivities and their small variations in the resistivity sections between the rainy and dry days. This trend suggests that the weathered gray volcanic rock and the nearby fractures with higher low porosity and moisture content are interpreted to be good carrier especially in rainy season.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.4
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• pp.136-145
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• 2009

Site characteristic is an important input parameter in the geologic hazard assessments including, but not limited to, earthquakes, liquefaction and landslides. Although it is a routine to use data collected by boreholes or seismic prospecting for site classifications, we used indirect methods using the geologic and the topographic maps. A site classification map in the Gyeongsang Province has been produced by GIS tools based on geologic age, rock types, and elevations from the geologic map and the topographic map of Korea. Site B (rock site) is dominant in the study area, although softer soils are observed along rivers and in reclaimed lands. We have found that 73% of the site classification results in the study are in concordance with those obtained from borehole data. Observed discrepancies are attributed to errors in the geologic and the topographic maps. For some sites, the origin of the differences is not clear, which requires a further field study or a drilling. Site classification from this study provides essential information for reliable hazard assessments of earthquakes, floods, landslides and liquefaction. Results obtained in the study also play a crucial role in land use planning for developing areas.

• The Journal of Engineering Geology
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• v.4 no.1
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• pp.91-93
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• 1994

• Proceedings of the KSEEG Conference
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• 2000.04a
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• pp.23-24
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• 2000

• Economic and Environmental Geology
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• v.1 no.1
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• pp.54-69
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• 1968

• Proceedings of the KSEG Conference
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• 2000.04a
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• pp.55-61
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• 2000

• Proceedings of the KSEG Conference
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• 2000.04a
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• pp.205-213
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• 2000

• Proceedings of the KSEEG Conference
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• 2001.04a
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• pp.92-94
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• 2001