• Proceedings of the Korean Society for Rock Mechanics Conference
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• 1999.03a
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• pp.69-71
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• 1999

이 논문은 대구-포항 간 고속도로 건설공사 지역 중 제 7공구 지역에 대한 지반조사를 목적으로 실시한 지질조사의 결과다. 기존자료는 1대 5만 기계도폭(오인섭과 정국성, 1975)과 이 지역을 포함한 소위 가음단층대의 동부지역에 대한 지질구조를 조사를 연구한 이병주와 황재하(1997)의 논문 등이 있다. 야외에서의 지질조사는 개설될 고속도로를 중심으로 발달하는 노두에서 암상의 특징과 층리, 절리 및 단층 등과 같은 불연속면의 발달 특성을 관찰 기재하였다.(중략)

• The Science & Technology
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• v.32 no.9 s.364
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• pp.12-14
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• 1999

재미한인과학기술자협회 신임회장 한홍택박사는 본지와의 대담을 통해 "앞으로 재미 2세 과학자들이 고국에 대한 관심을 많이 갖도록 하기 위해 그들을 위한 프로그램을 늘리고 8월 12일부터 열리는 한미종합학술대회에도 2세들이 많이 참여토록 했다"고 말했다. 한박사는 가볍고 강한 특성을 지닌 항공우주 구조물에 없어서는 안될 필수 복합소재의 설계와 제작에 관한 연구로 올해의 호암상 공로부문 대상을 받았다.

• Korean Journal of Plant Tissue Culture
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• v.22 no.2
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• pp.65-70
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• 1995

The synthesis of betalain in hairy root cultures of Phytolacca esculenta van Houtte required the light, but the growth of hairy roots was inhibited 5 times under light condition(1500 1X) compared to dark condition. To investigate the growth inhibition of hairy roots under light condition, we surveyed the effects of several antioxidants on growth and betalain production if suspension cultures of hairy roots was increased 1.2-1.4 times under dark condition and 1.3-1.9 times under light condition by the treatment of ascorbic acid, glutathione, $\alpha$-tocopherol, sodium pyrosulfate and propylgallic acid. The betalain production was increased 1.2-2.1 times by antioxidants under light condition. The combination treatment of antioxidants didn't have any significant effect on the growth of hairy roots and betalain synthesis. The antioxidants of the betalain production were more effect under blue light than others. It was discussed that the endogenous oxidants may be produced under blue light.

• Journal of the Korean earth science society
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• v.26 no.3
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• pp.297-304
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• 2005

Serpentinites in Chungnam area are mainly composed of serpentines. Serpentines of olivine origin consist of pseudomorphs of olivines and show mesh textureen closed with magnetites along the boundaries of serpentine crystals. In some serpentinites, serpentinization is occurred in crystal boundaries and/or cracks of olivines and pyroxenes which are relict minerals of dunite and harzburgite. On the process from olivine to serpentine, Mg ions are greatly decreased and Si ions are greatly increased, and $Fe^{2+}\;and\;Fe^{3+}$ ions are a little decreased. But, on the process from pyroxene to serpentine, Si ions are greatly decreased and Mg ions are greatly increased. Magnetites around the serpentine crystals were formed from the iron which had been left out through this serpentinization process of olivine. Serpentinization from the original rocks such as dunite and harzburgite in Chungnam area was occurred by various waters affected after formation of original rock, and particularly by metamorphic water in the metamorphic conditions ranging from green schist facies to granulite facies through amphibolite facies.

• Geophysics and Geophysical Exploration
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• v.1 no.3
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• pp.170-175
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• 1998

A systematic methodology is developed for the prediction of the lithology using electrofacies classification from wireline log data. Multivariate statistical techniques are adopted to segment well log measurements and group the segments into electrofacies types. To consider corresponding contribution of each log and reduce the computational dimension, multivariate logs are transformed into a single variable through principal components analysis. Resultant principal components logs are segmented using the statistical zonation method to enhance the quality and efficiency of the interpreted results. Hierarchical cluster analysis is then used to group the segments into electrofacies. Optimal number of groups is determined on the basis of the ratio of within-group variance to total variance and core data. This technique is applied to the wells in the Korea Continental Shelf. The results of field application demonstrate that the prediction of lithology based on the electrofacies classification works well with reliability to the core and cutting data. This methodology for electrofacies determination can be used to define reservoir characterization which is helpful to the reservoir management.

• The Journal of the Petrological Society of Korea
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• v.16 no.2 s.48
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• pp.73-81
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• 2007

A basaltic tuff formation (Upper Basaltic Tuff of the Janggi Group) occurs in close association with basalt (Yeonil Basalt) at the Tertiary Janggi basin. The purpose of this paper is to describe the occurrence of the basaltic tuff and associated basalt and to determine their mode of formation. The basaltic rocks of the study area show few distinct lithofacies, all of which are originated from the interaction of basaltic magma with external water. The four lithofacies include (1) sideromelane shard hyaloclastite, (2) pillow breccia, (3) entablature-jointed basalt, and (4) in-situ breccia. The sideromelane shard hyaloclastite constitutes most of the Upper Basaltic Tuff and has a gradual contact with the pillow breccia. The pillow breccia consists of a poorly sorted mixture of isolated and broken pillows, and small basalt globules and fragments engulfed in a volcanic matrix of sideromelane shard hyaloclastite. The entablature-jointed basalt occurs as a small body within the hyaloclastite. It is characterized by irregularly-curved joints known as entablature. The in-situ breccia occurs as a marginal facies of entablature-jointed basalt, and its width varies from 10 to 30m. The result of this study indicates that the basaltic tuff and associated basalts of the study area were produced by the volcanic activity of same period and the basaltic tuff was formed by subaqueous eruption of basaltic lava followed by nonexplosive quench fragmentation.

• The Journal of the Petrological Society of Korea
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• v.3 no.1
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• pp.49-75
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• 1994

The Hognjesa granitic rocks can be subdivided into biotite granitic gneiss and microcline- perthite granitic gneiss according to their mineralogy and textures, which change gradationally each other. They consist mainly of biotite, muscovite, chlorite, microcline, plagioclase, perthite and quartz accompanied with sillimanite, garnet, and tourmaline in places. The replacement and/or alteration phenomena and relationships of coexisting minerals suggest that the granitic gneisses might be formed by regional metamorphism of upper amphibolite facies and granitization by partial melting accompanied to the regional metamorphism, and again at later effected by regional metamorphism of epidote-amphibolite or greenschist facies. The biotite, muscovite and chlorite formed during these metamorphism, show nearly similar chemical compositions, respectively, regardless to the rock phases and stages of formation. They show relatively stable chemical equilibrium between coexisting pairs. The granitization which formed granitic gneisses may be seemed to occur regionally by partial melting accompanied to the first regional metamorphism.

• The Journal of Engineering Geology
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• v.28 no.4
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• pp.593-603
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• 2018

The most of groundwater with high U-concentration occur in the Jurassic granite of Gyeonggi massif and Ogcheon belt, and some of them occur in the Cretaceous granite of Ogcheon belt. On the contrary, they do not occur in the Jurassic granite of Yeongnam massif and the Cretaceou granite of Gyeongsang basin. The Jurassic and Cretacous granite, the host rock of high U-groundwater, were resulted from parental magma with high ratio of crustal material and highly differentiated product of fractional crystalization. These petrogenetic characteristics explain the geological evidence for preferential distribution of uraniferous groundwater in each host rock. It were reported recently that high U-content, low Th/U ratio and soluble mineral occurrence of uraninite in the two-mica granite of Daejeon area which have characteristics of S-type peraluminous and highly differntiated product. It is the mineralogical-geochemical evidences supporting the fact that the two-mica granite is the effective source of uranium in groundwater. The biotite granite and two-mica granite of Jurassic age were reported as biotite granite in many geological map even though two-mica granite occur locally. This fact suggest that the influence of two-mica granite can not be ignored in uraniferous groundwater hosted by biotite granite.

• The Journal of Engineering Geology
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• v.2 no.1
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• pp.36-46
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• 1992

Granite core samples and bulk samples were first subjected to petrographic examination to determine weathering degrees. Secondly, their physical or mechanical properties including specific gravity, porosity, sonic wave velocity and uniaxial compressive strength were measured. The results were correlated to investigate the influences between properties including physical and mechanical properties, weathering degrees, and rock textures. Porosity and P wave velocity were found the most useful indices in determining the weathering degrees of granites.

• Geophysics and Geophysical Exploration
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• v.16 no.4
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• pp.268-274
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• 2013

Continuous seismic observation of volcanic earthquakes related to migration of magma or gas, is one of the most important methods used to monitor active volcanoes. In this review paper, we introduce the characteristics of volcanic earthquakes and their classification based on locations of foci, waveforms, frequencies, lithology, and source mechanisms. We also present some examples of successful warnings of volcanic eruptions and the present status of some observations of volcanic earthquakes in Japan, the United States, Italy, and New Zealand.