• Korean Journal of Mineralogy and Petrology
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• v.34 no.1
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• pp.57-67
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• 2021

The geology of the Iskaycruz project are mainly composed of sedimentary rocks within Cretaceous basin. The basal part is composed up of dark-gray shale, gray sandstone, and clastic rock of Oyon formation interbedded with coal measures. In the folded zone in the eastern part of the survey area, there is Chimu formation that has medium-grained massive and white quarztite. In terms of geological structure, the Iskaykruz region is located in the folded and overthrust zones of the central part of the Occidental Mountains. Ore body was formed by hydrothermal replacement process and consists of zinc, lead, silver, and copper. Stratabound-type deposits are hosted in limestone of Santa formation. It extends 12 kilometers discontinuously from northern Canaypata to southern Antapampa. Irregular iron oxide and sulfide minerals hosted in Santa and Parihuanca formations are observed. The mineralization observed on the surface consist of primary sulfides consisting of sphalerite with galena and chalcopyrite, and iron and manganese oxide produced from oxidation of primary sulfides. Skarn minerals are accompanied by tremolite, garnet, epidote and quartz.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.1
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• pp.55-62
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• 2022

The functionally generated path (FGP) technique, first described by Meyer in 1933, is a method in the oral cavity to use the movement pathway formed by the opposing cusps within the border movement of the mandible. Using this method, an appropriate occlusal shape can be given to the patient. In this case, the FGP technique was selected to provide a bilateral balanced occlusion when restoring the edentulous maxilla that opposes the natural mandibular teeth with irregular arrangement with overdentures. In addition, in order to precisely form the occlusal surface of the posterior region with the FGP technique and to reduce the attrition of denture teeth, zirconia denture teeth, not conventional resin artificial teeth, were individually manufactured. After treatment with these materials and methods, satisfactory results were obtained for both the operator and the patient.

• Korean Journal of Ichthyology
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• v.33 no.1
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• pp.1-7
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• 2021

Using stereo, light, and scanning electron microscopes, we researched the anatomical and histological structure of Chaenogobius gulosus's olfactory organ and compared it to those of sympatric gobies Luciogobius guttatus and Favonigobius gymnauchen. Results revealed the following common characteristics: i) tubular anterior nostril (AN) and flat posterior nostril (PN), ii) a single longitudinal lamella, iii) two accessory nasal sacs (ANS, ethmoidal and lacrimal), iv) abundant sensory epithelium lymphatic cells (LC), v) an eosinophil cell, and vi) a ciliary length a quarter of the knob diameter in the olfactory receptor neuron (ORN). Some characteristics are specific to C. gulosus and different from the other two gobies: i) 0.5~1.0 mm AN and 0.2~0.5 mm PN (vs. 0.2~0.3 mm and 0.2~0.3 mm in L. guttatus; 0.2~0.4 mm and 0.1~0.3 mm in F. gymnauchen), ii) two ANS (vs. absence in L. guttatus; two in F. gymnauchen), iii) abundant LC (vs. low in L. guttatus and F. gymnauchen), iv) low density non-sensory cilia on the lamellar surface (vs. high in L. guttatus; low in F. gymnauchen), and v) a quarter ciliary length to knob diameter ratio in the ORN (vs. mixture of a quarter to equal ratio in L. guttatus; two or three times in F. gymnauchen). From these results, we confirmed the C. gulosus olfactory organ has adapted anatomically and histologically to the sand-rock tidal zone.

• Journal of Conservation Science
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• v.37 no.2
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• pp.77-89
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• 2021

In this study, materials and color formation techniques were assessed for black potteries excavated from the Janghyeon-dong, Jungsan-dong and Gyodong-ri sites during the Proto-Three Kingdoms period in Ulsan, Korea. Although the black potteries were black superficially, the inner cores were either black or reddish yellow. Microscopy analysis identified that body clay was used for reddish iron oxide rich soils with quartz, alkali feldspar and mica, along with grains of myrmechite texture. Additionally, as marginal differences exist in the contents of SiO₂, Fe₂O₃ and CaO, the composition of the host rock and clay distributed around the sites was affected. Thus, we can deduce that pottery was made by soiling at a short distance. Raman spectroscopy results revealed that the black layer of the black pottery was used as amorphous combustion carbon. In addition, as a transparent layer of brown lacquer was observed on the substrate that was in contact with the surface layer, the black layer of the pottery induced black color development by a combination of combustion carbon and lacquer. Based on the mineral composition and microtexture of the body clay, the firing temperature of the potteries seemed to range from 750 to 850℃, whereas the lacquer layer was pyrolyzed at 468℃ by thermal analysis. Therefore, a combined layer of combustion carbon and lacquer, which formed the black color, was painted after the body clay was fired.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.449-466
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• 2022

The establishment of a complete geological model that includes information about all the various components at a site (such as underground structures and the compositions of rock and soil underground space) is difficult, and geological modeling is a developing field. This study uses commercial software for the relatively easy composition of geological models. Our digital modeling process integrates a model of Jeju Island's 3D geological information, models of cave shapes, and information on the state of a road at the site's upper surface. Among the numerous natural caves that exist in Jeju Island, we studied the Jaeamcheon lava tube near Hallim town, and the selected site lies below a road. We developed a digital model by applying the principles of building information modeling (BIM) to the cave (CaveBIM). The digital model was compiled through gathering and integrating specific data: relevant processes include modeling the cave's shape using a laser scanner, 3D geological modeling using geological information and geophysical exploration data, and modeling the surrounding area using drones. This study developed a global-scale model of the Hallim region and a local-scale model of the Jaeamcheon cave. Cross-validation was performed when constructing the LSM, and the results were compared and analyzed.

• Economic and Environmental Geology
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• v.55 no.1
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• pp.53-61
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• 2022

The Gasado Au-Ag deposit is located within the south-western margin of the Hanam-Jindo basin. The geology of the Gasado is composed of the late Cretaceous volcaniclastic sedimentary rocks and acidic or intermediate igneous rocks. Within the deposit area, there are a number of hydrothermal quartz and calcite veins, formed by narrow open space filling along subparallel fractures in the late Cretaceous volcaniclastic sedimentary rock. Vein mineralization at the Gasado is characterized by several textural varieties such as chalcedony, drusy, comb, bladed, crustiform and colloform. The textures have been used as exploring indicators of the epithermal deposit. Mineral paragenesis can be divided into two stages (stage I, ore-bearing quartz veins; stage II, barren carbonate veins) considering major tectonic fracturing event. Stage I, at which the precipitation of Au-Ag bearing minerals occurred, is further divided into three substages (early, middle and late) with paragenetic time based on minor fractures and discernible mineral assemblages: early, marked by deposition of pyrite and pyrrhotite with minor chalcopyrite, sphalerite and electrum; middle, characterized by introduction of electrum and base-metal sulfides with minor argentite; late, marked by argentite and native silver. Au-Ag-bearing mineralization at the Gasado deposit occurred under the condition between initial high temperatures (≥290℃) and later lower temperatures (≤130℃). Changes in stage I vein mineralogy reflect decreasing temperature and fugacity of sulfur (≈10^-10.1 to ≤10^-18.5atm) by evolution of the Gasado hydrothermal system with increasing paragenetic time. The Gasado deposit may represents an epithermal gold-silver deposit which was formed near paleo-surface.

• Journal of the speleological society of Korea
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• no.4
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• pp.41-50
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• 1996

The coastal plains of the Puna and Ka' u Districts of the island of Hawaii are a contradiction to the popular view that the island of Hawaii is a tropical rain forest or a vegetated landscape with abundant water sour This section of the island lies in the rain shadow of Mauna Loa a Kilauea Volcanoes and receives less than 30 inches of annual precipita When rain does come. it is in the form of sudden down pours. givi residents of the area little time to collect and conserve water. Due to porous nature of the rock. there is no standing surface water. In spite of these harsh climatic conditions. archeological evidence indic that an extensive agriculture complex existed not only along the coast. into the most remote parts of what is called the Ka'u Desert. Pass through these agricultural areas are historic and pre - historic t systems. These trail systems apparently played a significant suppor role for exchange between the ahupua's (classic land divisions of Haw and the geopolitical districts. The question arises as to how could vast agricultural complexes a heavy foot travel over miles of arid land exist without dependable wa sources\ulcorner While planting - pits and mounds were designed to make most efficient use of available water and conserve moisture(Carter 19 9). people involved in planting also needed potable water for surv Most publications and research papers dealing with the early population this area make only oblique reference to springs and wells which t populations depended upon. The Federal Cave Resource Protection Act(1988) has served as imprtus for the National Park Service to look closer at the lava tu caves and fault cracks within Hawaii Volcanoes National Park. P visitors to these underground areas found large volumes of standing wa in fault cracks. and abundant drip areas with the lava tubes. Re observes noted that in most cases. where the cracks and caves we located in the arid sections of the park. there has been extens modifiacation or utilization of these water sources by the early Hawaii and others. The variety of western containers used for collection indica that these water sources were used during historic times. William E described similar water sources in his narrative of his trip around island in 1823(Eills 1979), This report is directed at documenting recent observations and a stimulating further research into early Hawaiian water collection syst It also explores the implications that power and political influence of e chiefs in the arid portions of Hawaii could have been linked to the con of the water resources.

• Journal of the Korean Geotechnical Society
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• v.25 no.10
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• pp.87-97
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• 2009

The seismic site coefficients are often used with the seismic hazard maps to develop the design response spectrum at the surface. The site coefficients are most commonly developed deterministically, while the seismic hazarde maps are derived probabilistically. There is, hence, an inherent incompatibility between the two approaches. However, they are used together in the seismic design codes without a clear rational basis. To resolve the fundamental imcompatibility between the site coefficients and hazard maps, this study uses a novel probabilistic seismic hazard analysis (PSHA) technique that simulates the results of a standard PSHA at a rock outcrop, but integrates the site response analysis function to capture the site amplification effects within the PSHA platform. Another important advantage of the method is its ability to model the uncertainty, variability, and randomness of the soil properties. The new PSHA was used to develop fully probabilistic site coefficients for site classes of the seismic design code and another sets of site classes proposed in Korea. Comparisons highlight the pronounced discrepancy between the site coefficients of the seismic design code and the proposed coefficients, while another set of site coefficients show differences only at selected site classes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1C
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• pp.65-76
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• 2010

Recent earthquake events revealed that severe seismic damages were concentrated mostly at sites composed of soil sediments rather than firm rock. This indicates that the site effects inducing the amplification of earthquake ground motion are associated mainly with the spatial distribution and dynamic properties of the soils overlying bedrock. In this study, an integrated GIS-based information system for geotechnical data was constructed to establish a regional counterplan against ground motions at a representative metropolitan area, Seoul, in Korea. To implement the GIS-based geotechnical information system for the Seoul area, existing geotechnical investigation data were collected in and around the study area and additionally a walkover site survey was carried out to acquire surface geo-knowledge data. For practical application of the geotechnical information system used to estimate the site effects at the area of interest, seismic zoning maps of geotechnical earthquake engineering parameters, such as the depth to bedrock and the site period, were created and presented as regional synthetic strategy for earthquake-induced hazards prediction. In addition, seismic zonation of site classification was also performed to determine the site amplification coefficients for seismic design at any site and administrative sub-unit in the Seoul area. Based on the case study on seismic zonations for Seoul, it was verified that the GIS-based geotechnical information system was very useful for the regional prediction of seismic hazards and also the decision support for seismic hazard mitigation particularly at the metropolitan area.

• Journal of Korean Society of Forest Science
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• v.56 no.1
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• pp.66-76
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• 1982

Soil harness represents such physical properties as porosity, amount of water, bulk density and soil texture. It is very important to know the mechanical properties of soil as well as the chemical in order to research the fundamental phenomena in the growth and the distribution of tree roots. The writer intended to grip soil hardness by soil layer and also to grasp the root distribution and the correlation between soil hardness and the root distribution of Pinus riguda Mill. planted on the denuded hillside with sooding works by soil layer on soil profile. The site investigated is situated at Peongchang-ri 13, Kocksung county, Chon-nam Province. The area is consisted of 3.63 ha having on elevation of 167.5-207.5 m. Soil texture is sandy loam and parant rock in granite. Average slope of the area is $17^{\circ}-30^{\circ}$. Soil moisture condition is dry. Main exposure of the area is NW or SW. The total number of plots investigated was 24 plots. It divided into two groups by direction each 12 plots in NW and SW and divided into three groups by the position of mountain plots in foot of mountain, in hillside, and in summit of mountain, respectively. Each sampling tree was selected as specimen by purposive sampling and soil profile was made at the downward distance of 50cm form the sampling tree at each plot. Soil hardness, soil layer surveying, root distribution of the tree and vegetation were measured and investigated at the each plot. The soil hardness measured by the Yamanaka Soil Hardness Tester in mm unit. the results are as follows: 1) Soil hardness increases gradually in conformity with the increment of soil depth. The average soil indicator hardness by soil layer are as follows: 14.6mm in I - soil layer (0-10cm in depth from soil surface), 16.2mm in II - soil layer (10-20cm), 17.2 in III - soil layer (20-30cm), 18.3mm in IV - soil layer(30-40cm), 19.8mm in V - soil layer (4.50mm). 2) The tree roots (less than 20mm in diameter) distribute more in the surface layer than in the subsoil layer and decrease gradually according to the increment of soil depth. The ratio of the root distribution can be illustrated by comparing with each of five soil layers from surface to subsoil layer as follows: I - soil layer; 31%, II - soil layer; 26%, III - soil layer; 18%, IV - soil layer; 12%, V - soil layer; 13%, 3) Soil hardness and tree root distribution (less than 20mm in diameter) of Pinus rigida Mill. correlate negatively each other; the more soil hardness increases, the most root distribution decreases. The correlation coefficients between soil hardness and distribution of tree roots by soil layer are as follows: I - soil layer; -0.3675 (at the 10% significance level), II - soil layer; -0.5299 (at the 1% significance level), III - soil layer; -0.5573 (at the 2% significance level), IV - soil layer; -0.6922 (at the 5% significance level), V - soil layer; -0.7325 (at the 2% significance level). 4) the most suitable range of soil hardness for the growth of Pinus rigida Mill is the range of 12-14.9mm in soil indicator hardness. In this range of soil indicator hardness, the root distribution of this tree amounts to 41.8% in spite of 33% in soil harness and under the 20.9mm of soil indicator hardness, the distribution amounts to 93.2% in spite of 82% in soil hardness. Judging from above facts, the roots of Pinus rigida can easily grow within the soil condition of 20.9mm in soil indicator hardness. 5) The soil layers are classified by their depths from the surface soil.