• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.1018-1027
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• 2004

The purpose of this study was to identify and compare the types of scientific questions which were generated by elementary students and preservice teachers on the tasks of scientific observation. To identify the types of scientific questions, 4 observing tasks, dry grapes contained in soda pop, candlelight, celery, and a rock were administered to 40 sixth elementary students and 20 elementary preservice teachers. And then, the types and frequency of scientific questions generated by them were compared. The results showed that the types of scientific questions were classified into conjectural questions, causal questions, predictive questions, methodical questions and applicative questions. Further more, subordinate questions to the above questions were classified into object exploration questions and object verification questions, explicans exploration questions and explicans verification questions, result exploration questions and result verification questions, example exploration questions and example verification questions. Subordinate questions did not come out from the methodical questions. The types of scientific questions generated by elementary students and preservice teachers were identical, however, there were differences in frequency. This study supports that elementary students also have cognitive capability to generate various scientific questions. The results of this study may be used as a teaching strategy for the guidance of the direction and the method of scientific inquiry.

• Journal of the Mineralogical Society of Korea
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• v.18 no.3 s.45
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• pp.165-181
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• 2005

The granitic rocks distributed in the southern part of the Yangsan Fault are classified into five distinct rock facies based on the field relation, petrography and geochemical characteristics. These five different rock facies can be grouped into two considering their origins. Group I, which reveals various evidences of magma mixing, includes three rock facies of granodiorite, enclave-rich porphyritic granite, and enclave-poor porphyritic granite. Group H intruding Croup I includes equigranular granite and micrographic granite with no evidence of magma mixing. It is suggested that the distinctively different trace element and isotopic chemistries between group I and II, support evolution from the different parental magma. It is suggested that the three rock facies in group I were generated by different degrees of magma mixing in addition to fractionation of plagioclase. MMEs experienced fractionation of biotite. The two facies in group H seem to have been generated from different parent magma from group I and evolved by fractionation of K-feldspar. The Rb-Sr whole-rock ages of the group I rocks yield $59.2\~58.9Ma$, and those of the group II rocks give 53. $3\~51.7Ma$, regardless of their distribution whether they occur in the eastern or western parts of the Yangsan Fault. Based on Sm-Nd isotope compositions, depleted mantle model ages $(T_2DM)$ of the group I range $0.8\~0.9Ga$, while those of the group II$0.6\~0.7Ga$.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.239-256
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• 2017

In the process of site selection for a radioactive waste disposal, site characterization must be carried out to obtain input parameters to assess the safety and feasibility of deep geological repository. In this paper, methodologies of site characterization for radioactive waste disposal in Korea were suggested based on foreign cases of site characterization. The IAEA recommends that site characterization for radioactive waste disposal should be performed through stepwise processes, in which the site characterization period is divided into preliminary and detailed stages, in sequence. This methodology was followed by several foreign countries for their geological disposal programs. General properties related to geological environments were obtained at the preliminary site characterization stage; more detailed site characteristics were investigated during the detailed site characterization stage. The results of investigation of geology, hydro-geology, geochemistry, rock mechanics, solute transport and thermal properties at a site have to be combined and constructed in the form of a site descriptive model. Based on this site descriptive model, the site characteristics can be evaluated to assess suitability of site for radioactive waste disposal. According to foreign site characterization cases, 7 or 8 years are expected to be needed for site characterization; however, the time required may increase if the no proper national strategy is provided.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.573-582
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• 2008

We report a newly found natural habitat of Abeliophyllum distichum in mountainous slope range of Yeongdong-gun, Chungbuk Province. Abeliophyllum distichum Nakai is one of the Korean monotypic endemic species. Natural growth habitats of this species have been recorded from seven sites up to now, and all of the natural habitats are located in middle (Chungbuk Prov.) and middle west (Jeonbuk Prov.) parts of South Korea. Among the previously recorded seven natural habitats, six sites have been designated as Korean national monuments and protected with in situ conservation. New natural habitat of A. distichum is located on northwest slope of stiff hillock area beside the small stream, Seolgye-ri, Yeongdong-eup, Yeongdong-gun, Chungbuk Province. Total growing area is nearly $3,000 m^2$. It is 10-25 cm in soil depth and pH 5.0-6.5 in soil acidity in that area. And many of A. distichum are clustered with 2-5 individuals extended by stoloniferous asexual reproduction. And the total numbers of A. distichum are about 700 individuals with only typical white flowers, and the ratio between pin type and thrum type is 37% and 63%, respectively. The huge population of A. distichum is growing with Quercus mongolica-Fraxinus rhynchophylla association in a mixed forest, and it shows high affinity with Stephanandra incisa, Ligustrum obtusifolium, Euonymus alatus for. ciliatodentatus, and Smilax sieboldi.

• Journal of the Mineralogical Society of Korea
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• v.17 no.4
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• pp.365-383
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• 2004

Granitic rocks in the southeastern Gyeongsang Basin can be classified into three groups. The group I contains various mafic microgranular enclave (MME) and/or mafic clot which implies magma mixing or mingling. The group II show the feature of shallow depth emplacement at low pressure, and the group III is characterized by A-type granite implying extensional tectonic environment. Mineralogical characteristics of the granitic rocks have showed systematic variations in perthite exsolution temperatures and biotite compositions according to their rock facies, although they do not show any distinctively different trend in geography and textures or rock facies. Amphiboles from Group I are calcic-amphibole and they were formed at 0.4 ～ 2.8 kb in pressure based on the amphibole geobarometry. Amphiboles from group ill are riebeckite, whileas amphiboles were not observed in Group II. The chemical composition of biotite defined in clusters showing a continuous spectrum between group I to ferric-annite of group ill. The composition of plagioclase generally plotted in albite, oligoclase, and andesine area without any distinctive differences among their geography or rock facies. The exsolution temperatures by perthite geothermometry are calculated as $300～400^{\circ}C$ in Group I, and 500～$600^{\circ}C$ in equigranular granite of group II and alkali-feldspar granite of group III.

• Journal of the Mineralogical Society of Korea
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• v.6 no.1
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• pp.27-37
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• 1993

The clay minerals such as sericite, pyrophyllite, chlorite and smectite abundantly occur in the Bobae pottery stone mine in Pusan. In this study, the processes which are responsible for the formation of these minerals were studied by examing their occurrence and mineralogical properties. The so-called pottery stone of this mine is characterized by the predominance of sericite and quartz. The sericite of the pottery stone is mostly $2M-{1}$ type. And many of quartz particles are smaller than a few micron in diameter. The pottery stone also contained a small amount of pyrophyllite and muscovite. The pottery stone deposit occurs within the Cretaceous rhyodacite and is particularly well developed near the contact with the quartz porphyry which intrudes the rhyodacite. The fact implies that the pottery stone is the product of hydrothermal alteration of the rhyodacite by the intrusion of quartz porphyry. The pottery stone was formed by the alteration that accompanies the dissociation of feldspar and chlorite in parent rocks and subsequent formation of sericte and quartz. Smectite, laumontite and kaolinite occur locally within the altered rocks. These minerals were formed after formation of pottery stone. It is noteworthy that beidellite occurs as a pink-colored clay from the altered rocks in the mine.

• Journal of the Mineralogical Society of Korea
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• v.20 no.2 s.52
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• pp.103-114
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• 2007

Gabbroic xenoliths in poikilitic and equigrnular textures and plagioclase megacrysts, up to 15 cm in size, are trapped in alkaline basalts from Sinsanri and Sangeumburi, Jeju island. Gabbroic xenoliths are gabbro norite in composition. Plagioclase is the most dominantly present $(42{\sim}94vol%)$, while olivine crystals are absent. Pokilitic xenoliths, interpreted as cumulates, include euhedral opx+cpx in oikocryst plagioclase. Equigranular xenoliths include subhedral to anhedral opx+cpx+pl. Based on the textural and geochemical natures, occurrence mode at the outcrops, poikiltic and equigranular xenoliths and plagioclase megacrysts were from rigid zone, mushy zone and crystal-suspended zone of the magma chamber, respectively. The gabbroic xenoliths in alkaline basalts of the Juju island represent crystallization products of relatively evolved basaltic magma at the Jeju magma reservoir beneath the Jeju Island. They are gabbro fragments that represent crystallization-isolation-capture processes associated with magma batches temporarily occupying reservoirs.

• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.331-342
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• 2009

Groundwater samples were collected from the bedrock aquifers related with Okcheon metasedimentary rocks. Arsenic (As) concentrations in the samples varied between 0.0051 and 0.887 mg/L, with an average of 0.0248. Cations and anions of groundwaters had no relationship with As contents as well as with spatial distribution of geology in the area. Pyrite, chalcopyrite and arsenopyrite in the core samples of the monitoring wells were identified in thin section, X-ray diffraction (XRD) and electron probe microscope analysis (EPMA). It was suggested that these minerals are responsible for the As in groundwater. The groundwater showed saturations with respect to calcite $(CaCO_3)$, dolomite (CaMg$(CO_3)_2$) and Magnesite $(MgCO_3)$. $HAsO_4{^{2-}}$ activities in the groundwater samples were close to $Ca_3(AsO_4)_2(c)$ and $Mn_3(AsO_4)_2(c)$ solubility isotherms, indicating that the maximum As contents in groundwater are secondly controlled by the precipitation and dissolution of carbonate minerals due to alkaline and oxic nature of the groundwater (pe+pH>10).

• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.297-305
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• 2009

Ores of the Jeonnam pyrophyllite province mainly consist of not only pyrophyllite but also kaolinite, and they usually contain minor amounts of muscovite and quartz. We usually call them as porcelaneous stones which usually show lower grade characteristics in the viewpoint of Korean nonmetallic industries. Mineralogical studies for the ores and their intimate formations revealed that another kind of clay minerals could have been produced from the volcanic sediments with similar ages and compositions. Corundum is commoner than the diaspore in the pyrophyllite deposits, and so diaspore can be regarded as one of temporary minerals from which corundum would be finally formed. Kaolinite deposits contain neither diaspore nor corundum, but alunites produced by an advanced argillic alteration are often observed in the upper portions of the kaolin ores. The lowest formation interbedded with pyrophyllite and/or kaolinite ores usually contain purple tuff bed on the uppermost part, and in ascending order, siliceous formation, fine ash tuff and lapillistone are found in the study areas. As ages are becoming younger, amounts of pyrophyllite and kaolinite are radically decreased, or disappeared completely. On the other hand, content of muscovite is slightly increased, and those of plagioclase feldspars and quartz are found to have been preserved from the original rocks during alteration process. Most of ore bodies show rather well bedded formations which are easily discernable in the outcrops, but more effective discremination is desirable where rather massive ores exist. Siliceous beds and purple tuff ones on the upper part of ore bodies would be useful as marker horizons or key beds which have distinct lithologies and extensions.

• Journal of the Korean Institute of Landscape Architecture
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• v.17 no.3
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• pp.21-34
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• 1990

Trail and campground deteriorations and their environmental changes of soil and vegetation were studied in Tonghwa -Sa district of Mt. Palgong Natural Park through 1988 into 1989. The results are summarized as follows : 1. The bare width of trail as one of the trail condition factor was significantly greater on the more heavily used trail. Deterioration types of trail which had higher frequency for a total of 45 observations were rock exposure(42%), trail deepening(40%) and root exposure(18%) in the high order. And also sound type on which the trail was not deteriorated at all amounted to 33% of all observations. 2. Ecological changes of soil and vegatation of trailsides were not found at a uniform tendency except that soil hardness was slightly decreased from trail edge to the forest, but they could be grouped by the type of user\`s behavior and site conditions. Use impacts on the natural environment of trailside in Mt. Palgong are still far from the severe harmulness. 3. Worse damages to compground condition were appeared in Bawi-gol than Susu-gol campsite. Types of mechanically damaged trees were tree with exposed root(63% ), scared tree(43% ), mutilated tree(30 % ) and felled tree in highly frequent order. And diameter increments of trees in campsites were oppressed by the campers. 4. Tree damage types and their frequencies could be basic as a means of which grasp the bounds of user's impacts. User's disturbance on campsite extended to the distance of 70∼90m from the core of campsite at Pawi-gol and 20∼30m at Susu-gol respectively. As the tolerant trees to use impact, Lespedeza maximowiczii, Rhus trichocarpa, Acer palmatum, Rubus crataegifolius and Celastrus orbiculatus were considered.