• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.3
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• pp.273-281
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• 2001

The landslide occurrence in Sam-Chuck area was analyzed through Geo-Spatial Information System and AHP(Analytic Hierarchy Process). Among many factors which causes landslide, terrain slope, terrain aspect, lithology, soil texture and vegetation arc taken as input data from existing maps and constructed as a database. These factors are determined by each environmental factor by environmental and geological characters in the study area, and the rating and weight about factor are input using AHP. Possible areas for landslide have been extracted by overlaying each layers. Finally, the estimated results are compared with real landslide sites to know which factor is the most effective for landslide. The results showed that lithology and soil factor have high susceptibility in Sam-Chuck area.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.13-14
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• 2003

It is generally well known that Quaternary is characteristic geologically in terms of glacial and interglacial repeats and their associated unconformity formation. This paper deals with the first finding of the characteristic and significant meaningful unconformity between Holocene and late Pleistocene, which implies submergence and emergence of the tidal sedimentary basin along the western coastal zone of Korea during interglacial stage(IOS-5e) and glacial time(IOS-2). The stratigraphy of intertidal deposits in the Haenam Bay, western coast of Korea shows two depositional sequence units (Unit I of Holocene and Unit II of late Pleistocene) bounded by an erosional surface of disconformity. The disconformity is related to the latest Pleistocene sea-level lowstands (probably during the LGM). The Unit II is interpreted as intertidal deposit showing tidal sedimentary structures and crab burrow ichnology and has two parts (the upper part and the lower part) showing different lithology and character. The upper part of Unit II shows characteristic subaerial exposure features (emergence) and its related lithology. Such subaerially exposed upper part (more or less 4m to 5m in thickness) is characterized by yellow-brownish sediment color, cryoturbat-ed structure, crab burrow ichnofacies and high value of shear strength. Geochemical and clay mineral analyses of the upper part sediments also indicate subaerial exposure and weathering. In particular, very high value of magnetic susceptibility of the upper part in comparison to that of the lower part is interpreted as pedogenetic weathering during the subaerial exposure period.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.117-122
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• 2005

The purpose of this study is to analyze a correlation between lithology, rock physical property and fracture zone by multiple-logging method, which includes optic borehole image, suspension type PS, resistivity, SP, natural gamma, density, caliper logging located in Ogar test area, Changsu, Pocheon-gun, Gyunggi Province. The outstanding geophysical logging responses particularly shown from lithology pattern, fracture zone, dike zone. in result, the depth of fracture zone which enable groundwater flow estimated at $67{\sim}69m$.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.306-309
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• 2004

The susceptibility of landslides and the effect of landslide-related factors at Penang in Malaysia using the Geographic Information System (GIS) and remote sensing data have been evaluated. Landslide locations were identified in the study area from interpretation of aerial photographs and from field surveys. Topographical and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. The factors chosen that influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature and distance from drainage, all from the topographic database; lithology and distance from lineament, taken from the geologic database; land use from Landsat TM (Thermatic Mapper) satellite images; and the vegetation index value from SPOT HRV (High Resolution Visible) satellite images. Landslide hazardous areas were analysed and mapped using the landslide-occurrence factors employing the probability-frequency ratio method. To assess the effect of these factors, each factor was excluded from the analysis, and its effect verified using the landslide location data. As a result, land 'cover had relatively positive effects, and lithology had relatively negative effects on the landslide susceptibility maps in the study area. In addition, the landslide susceptibility maps using the all factors showed the relatively good results.

• Economic and Environmental Geology
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• v.32 no.1
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• pp.1-11
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• 1999

In the last decade, the supply of natural aggregates has been continuously increased due to the other types of aggregates. In general, aggregates constitute 70-80% of the total volume of concrete, so the quality of aggregates is main factor controlling physical characteristics of concrete. For this reason, physical properties of aggregate according to different rock types were studied. The majority of crushed aggregates is taken out of granite, gneiss, sandstone, andesite, basalt and so forth. The physical properties of these rock types were tested and most of them fell within the acceptable limit on the base of Korean standard regulation. The major lithology of the crushed aggregates is granite and gneiss, both of which are marked for more than 50% of total lithology thpes in Korea. A to the physical properties of granite, the high specific gravity coincides with low porosity, low absorption ratio, while the abrasion and soundness index show, in general, no specific trend. It has been assumed that slight differences of the physical properties of granite aggregates are related with those of the mineral composition, grain size, and so on. In comparison to granite, the physical properties of gneiss have little correlation one after another. This trend is related to different mineral composition, grain size and typical sheet fractures typically prevailing in the texture of gneiss. Spatial pattern of physical properties shows that high specific gravity of granite coincides only with low porosity and absorption ratio in all provinces except Cheolla province, and high specific gravity of gneiss coincides with low porosity and absorption ratio only in Cheolla and Gandwon provinces.

• The Journal of Engineering Geology
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• v.12 no.2
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• pp.127-135
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• 2002

The relationship between the seismic velocity and RQD was estimated using the RQD data obtained from the optical borehole image processing and drill core logs and the seismic velocity measured from the PS logging. The seismic velocity and crack aperture show a high correlation in the granite in Yuseong area and banded gneiss in Paldang area. However, such a relationship cannot be found in the sedimentary rock in Sabuk area. In the sedimentary rock of Sabbuk area, the seismic velocity shows widespread distribution especially in the 0∼20mm range of accumulated crack aperture probably because the wide distribution of fracture zone in coaly shale results in the inaccurate measurements of the crack aperture.

• Economic and Environmental Geology
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• v.25 no.4
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• pp.463-477
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• 1992

The study area consists of sedimentary and volcanic rocks of Gyeongsang Supergroup, granitoid intrusives, and hornfelses around the granitoids. Granitoid intrusives occur in small stocks in Nijeon-ri, Uggogri, and Yul-ri area. The masses in Nijeon-ri and Uggog-ri are hornblende-biotite granodiorite, biotite granodiorite respectively, and Yul-ri mass is biotite granite. Surrounding sediments of these masses were thermally metamorphosed and contact aureoles were formed. The studied granitoids are considered to be formed by sequential crystallization-differentiation from calc-alkalic granitoid magma. Metamorphic minerals occurring in contact aureole are chlorite, actinolite, epidote, and biotite. Diopside and hornblende are observed in small amount in some lithology around contact aureole. The lithology of contact aureole is predominantly silty and sandy, and characteristic metamorphic minerals were poorly developed because of low temperature metamorphism. Low temperature in contact aureole could be deduced from the facts that the intrusions were small size, shallow depth, low temperature, and rare movement of volatiles from magma.

• Geosciences Journal
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• v.22 no.6
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• pp.1027-1039
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• 2018

Seismic attributes are often used to identify lithology and evaluate reservoir properties. However, interpretation based only on structural attributes and without knowledge of the Vp/Vs ratio can limit the ability to evaluate changes in heavy oil reservoirs. These limitations are often due to less obvious impedance differences. In order to investigate pieces of evidence of a heavy-oil shaly-sand reservoir from seismic data, besides geochemistry, we studied seismic attributes and characterized the reservoir using seismic stack data and well logging data. The study area was the Muglad rift basin in South Sudan. We conducted a seismic complex analysis to evaluate the target reservoir. To delineate the frequency responses of the different lithological units, we applied the spectral decomposition method to the target reservoir. The most unexpected result was continuous bands of strong seismic reflectors in the target reservoir, which extended across the borehole. Spectral decomposition analysis showed that the low-frequency zone of 25 Hz dominant frequency was consistent with instantaneous attributes. This approach can identify lithology, reveal frequency anomalies, and filter the stacked section into low- and high-frequency bands. The heavy-oil reservoir zones exhibited velocity attenuation and the amplitude was strongly frequency dependent.

• The Korean Journal of Quaternary Research
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• v.21 no.2
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• pp.56-57
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• 2007

• Journal of the Korean association of regional geographers
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• v.9 no.2
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• pp.169-179
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• 2003

The hardness and physical properties of soils were measured in hiking trails of Mt. Halla and Darangshiorum in Jeju Island to examine the characteristics and formative factors of an aquiclude induced by human trampling. The soil hardness, being generally the highest on trails, decreases outward and shows the lowest on adjacent slopes in a natural condition. The bulk density and solid phase also demonstrates a similar tendency, then implying that the aquiclude occurs in the central part of trails. Although the formation of a hard layer in trails is fundamentally attributed to human trampling, the environmental factors such as landform, lithology, soil and vegetation play a role in the occurrence of the aquiclude. Soil compaction varies with the gradient and location of trails which affects a transport and deposition of soil particles to produce a hard layer. Soil compaction also depends on the physical properties of soils including the soil texture largely affected by lithology. Vegetation is not directly related with the formation of a hard layer, but affects its dimensions through an enlargement rate of bare trails depending on the response and resistance of plants to human trampling.