• Journal of Ginseng Research
• /
• v.28 no.1
• /
• pp.52-59
• /
• 2004

The ginsengs showing different ages(1, 2 and 3 years) are collected from the granite, phyllite and shale area. Keumsan and are analysed for the incompatible elements with the soils. In the soils, granite areas are high in the most of element and shale areas show high correlations among the element pairs. In the comparisons for differences of ginseng ages within the same area, granite and phyllite areas are high in the 2 year ginsengs while the shale ares are high in the 3 year ginsengs in the most of the elements. Positive correlations are dominant regardless area differences and high correlations are shown in the 3 year ginsengs, indicating the absorptions of the eligible element content with increasing ages. In the comparisons of area for the ginsengs of the same age, Rb, Cs and Ga, in the case of the granite area, are low in the 2 year ginsengs while most of elements are low in the 3 year ginsengs. High element contents are shown in the shale area, which are compared with granite and phyllite areas, indicating differences of dominant minerals. In the comparisons of the parts, upper parts are mainly high. High correlations are shown in the 3 year ginsengs, suggesting the similarities of absorption degrees within root as well as upper parts with the age. In the comparisons between soils and ginsengs, elements except Ba and Sr, are mainly high in the soils.

• Journal of the Korean Institute of Gas
• /
• v.25 no.1
• /
• pp.20-29
• /
• 2021

During multi-stage fracturing in a low permeable shale formation, stress interference occurs between the stages which is called the "stress shadow effect(SSE)". The effect may alter the fracture propagation direction and induce ununiform geometry. In this study, the stress shadow effect on the hydraulic fracture geometry and the well productivity were investigated by the commercial full-3D fracture model, GOHFER. In a homogeneous reservoir model, a multi-stage fracturing process was performed with or without the SSE. In addition, the fracturing was performed on two shale reservoirs with different geomechanical properties(Young's modulus and Poisson's ratio) to analyze the stress shadow effect. In the simulation results, the stress change caused by the fracture created in the previous stage switched the maximum/minimum horizontal stress and the lower productivity L-direction fracture was more dominating over the T-direction fracture. Since the Marcellus shale is more brittle than more dominating over the T-direction fracture. Since the Marcellus shale is more brittle than the relatively ductile Eagle Ford shale, the fracture width in the former was developed thicker, resulting in the larger fracture volume. And the Marcellus shale's Young's modulus is low, the stress effect is less significant than the Eagle Ford shale in the stage 2. The stress shadow effect strongly depends on not only the spacing between fractures but also the geomechanical properties. Therefore, the stress shadow effect needs to be taken into account for more accurate analysis of the fracture geometry and for more reliable prediction of the well productivity.

• Journal of the Mineralogical Society of Korea
• /
• v.24 no.4
• /
• pp.313-320
• /
• 2011

Mica-type phyllosilicate particles in the shales of the Manhang formation at the Taeback area in the Kangwon Province were studied using electron probe microanalysis (EPMA) and transmission electron microscopy (TEM). The average chemical formula of the mica-type phyllosilicate mineral analysed by EPMA is $K_{1.35}(Fe_{0.18}Mg_{0.03}Al_{3.86})(Si_{6.55}Al_{1.45})O_{20}(OH)_4$. Low K contents compared to the ideal chemistry of muscovite indicate the presence of illite in the mica-type phyllosilicate particle. X-ray diffraction study showed that pyrophyllite commonly coexists with muscovite in the shales from the Manhang Formation. TEM observations showed both the interlayer and intralayer mixing of $9.3-{\AA}$ pyrophyllite and $10-{\AA}$ muscovite layers. The low K content of the mica-type phyllosilicates apparently come from the close mixing of pyrophyllite and muscovite.

• Tunnel and Underground Space
• /
• v.26 no.4
• /
• pp.293-303
• /
• 2016

Underground $CO_2$ storage technology is one of the most effective methods to reduce atmospheric $CO_2$. In this study, $CO_2$ storage condition was simulated in the laboratory. Sandstone and shale specimens were saturated in 1M NaCl and were reacted at $45^{\circ}C$, 10 atm for 4 weeks. The physical and microstructural properties of rock specimens were measured. Variations on physical properties of shale specimens were bigger than those of sandstone specimens, such as volume, density, elastic wave velocity, Poisson's ratio and Young's modulus. Microstructure were analyzed using X-ray computed tomography. Total number of pores were decreased, and average volume, average area and average equivalent diameter of each pore were changed after $CO_2$ reaction. Swelling and leakage of clay mineral caused by $CO_2$-mineral reaction were the reason of changes. The results of this study can be applied to predict the physical and microstructural changes in underground $CO_2$ storage condition.

• Transactions of the KSME C: Technology and Education
• /
• v.1 no.1
• /
• pp.91-98
• /
• 2013

Shale gas is in the limelight as one of the new energy sources under the circumstances of unstable energy supply and high energy consumption. It is expected to change dynamics of global energy markets due to its abundant resources and global distribution. Shale gas extraction process consists of drilling, fracturing and production. We have surveyed the technologies required for shale gas developments such as a horizontal drilling, a hydraulic fracturing and so on, the environmental issues occurred during the development, the additional technologies to solve the environmental problems and the current research and developments status.

• Geophysics and Geophysical Exploration
• /
• v.10 no.4
• /
• pp.393-398
• /
• 2007

Seismic traveltime tomography technique was conducted at a site composed of black shale. It is well known that black shale has strong anisotropic property. Therefore, the anisotropic property of black shale has to be considered to obtain the appropriate subsurface velocity model by an inversion process. To estimate the anisotropic constant of the velocity of the black shale in the survey area, the relation between the velocity, which is calculated by the straight ray path and the first arrival time, and the angle of the ray propagation was examined. The elliptically shaped relation was found and it reveals that the black shale contains the anisotropic property of velocity. It was also noticed that the horizontal velocity is faster than the vertical velocity. When the estimated anisotropic constant was applied in the process of the velocity inversion for three sets of field data, we could obtain the appropriate velocity structures of the site that is consistent with the result of the geological survey.

• 한국해양학회지
• /
• v.22 no.2
• /
• pp.87-104
• /
• 1987

The middle Cretaceous stratigraphec section of Deep Sea Drilling Project (DSDP) Site 530 in the Angola Basin is characterized by cyclic interbeds of organic-carbon-rich black shales and organic-carbon-poor red and green claystones, namely the black shale sequence. A number of samples from the black shale sequence were analyzed for the typesand distribution of insoluble sedimentary organic matter(kerogen) in order to give more information on the depositional conditions of the black shales in the Angola Basin. The dominant type of kerogen in the black shale sequence at Site 530 is amorphous organic matter mainly of marine planktonic algal origin. It probably consists of remains of some unfossiliqed dinoflagellates. The cyclic preservation of organic-carbon-rich black shales in the Angola Basin during the mid-Cretaceous could be explained by the low dissolved-oxygen concentration in the warm, saline deep and bottom waters combined with the sluggish circulation within the highly restricted basin, and the periodic high productivity in the surface waters.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.23 no.4
• /
• pp.17-22
• /
• 2023

This study analyzed the genres of popular character web dramas and studied the development of story recommendations through the language model GPT. As a result of the study, it was confirmed that similar cliches are repeated in web dramas. In this study, a common story structure (cliché) was analyzed and a typical story structure was standardized and presented so that even unskilled video producers can easily produce character web dramas. For analysis, clichés of web dramas in the school romance genre, which is the most popular genre among teenagers, were listed in order of success. In addition, this study studied the story recommendation mechanism for users by learning the clichés that were analyzed and cataloged in GPT. Through this study, it is expected to accelerate the production of various contents as well as popular popularity through the acceptance of various databases from the standpoint of database consumption theory of web contents.

• The Journal of the Petrological Society of Korea
• /
• v.7 no.2
• /
• pp.132-145
• /
• 1998

The coal-bearing siliciclastic rocks of the Lower Permian Jangseong Formation, Samcheog coalfield, represent a megacyclothem which shows cyclic repetitions of sandstone, shale, coaly shale, and coals. Petrographic, geochemical, and SEM studies for sandstone samples, and XRD analysis for clay minerals were carried out to understand diagenesis in the sandstones of the Jangseong Formation. The Jangseong sandstones are composed of 60% quartz (mainly monocrystalline quartz) and 36% clay matrix and cement with minor amounts of feldspar, lithic fragments and accessory minerals (less than 4%). Jangseong sandstones are classified mostly as quartzwackes and partly as lithic graywackes according to the scheme of Dott(1964). The textural relationships between authigenic minerals and cements in thin sections and SEM photomicrographs suggest the paragenetic sequence as follows; (1) mechanical compaction, (2) cementation by quartz overgrowth, (3) formation of authigenic clay minerals (illite, kaolinite), (4) dissolution of framework grains and development of secondary porosity, and (5) later-stage pore-filling by pyrophyllite. We propose that these diagenetic processes might be due to organic-inorganic interaction between the dominant framework grains and the formation water. The Al, Si ions and organic acid, derived from dewatering of interbedded organic-rich shale and coals, were transported into the Jangseong sandstones. This caused changes in the chemistry of the formation water of the sandstones, and resulted in overgrowth of quartz and precipitation of authigenic clay minerals of kaolinite and illite. The secondary pores, produced during dissolution of clay and framework grains by organic acid and $CO_2$ gas, were conduit for silica-rich solution into the Jangseong sandstones and the influx of silica-rich solution produced the late-stage pyrophyllite after the expanse of kaolinite. The origin of the solution that formed pyrophyllite is not likely to be the organic-rich formation water based on the observation of fracture-filling pyrophyllite in the Jangseong sandstones, but the process of pyrophyllite pore-filling was indirectly related to organic-inorganic interaction.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.54 no.1
• /
• pp.61-79
• /
• 2009

This study is for incompatible element contents of Perilla frutescens and Sesamum indicum from the Keumsan: biotite granite, phyllite and shale areas. In the soils, high elements are shown in the granite and phyllite areas, and in the areas of the Perilla frutescens. Positive correlations are distinctive within the granite for the Perilla frutescens, but the shale for the Sesamum indicum. These relationships can be explained with relative propositions of minerals containing the incompatible element. In the plants, high elements are shown in the shale and the Sesamum indicum are high in the comparisons of the same soil types. The low parts are mainly high. Regardless of the soil types, the lower and upper parts, respectively, are high in the Y, Zr and Rb contents for the Perilla frutescens, but, Ta, Nb, Th and U contents for the Sesamum indicum. Positive correlations are distinctive within plants of the phyllite. Comparing with the soil types, all HFS and Cs contents of the LFS in the plants are low with differences of several to hundred times, but high in the Sr contents with differences of several times. In the comparisons between plants and soil types, Y, Zr, Hf, Ta, Nb, Rb, and Sr of the phyllite and Th, U, Ba and Cs of the shale for the Perilla frutescens as well as Y, Zr, Hf, Rb, Sr, Ba and Cs of the phyllite and Ta, Nb, Th and U of the shale for the Sesamum indicum are chemically similar to the soils. In the comparisons of the each parts for the plant types, differences with the soils are big in the granite.