• The Journal of Engineering Geology
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• v.24 no.1
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• pp.101-110
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• 2014

This study presents the results of a regression analysis of the point-load strength ($I_{s(50)}$) and the uniaxial compressive strength (UCS) of granites in Korea. The regression was carried out for three cases using the least-squares method, reclassifying the granite samples based on their physical properties. The first regression analysis through the origin according to the weathering grade did not give a result with a sufficient degree of confidence, due to the small number of samples. However, the general trend of the correlation between UCS and $I_{s(50)}$according to weathering grade shows that the slope of the linear regression for weathered granite is steeper than that for fresh granite. The second analysis was a simple linear regression for all the granite samples using the least-squares method as well as a linear regression using the bootstrap resampling method in order to increase the confidence level and the accuracy of the regression results. The third regression considered the average strength of granite groups reclassified according to physical properties. These linear regression analyses yielded linear regression equations with slopes of 14 and small standard deviations being similar to values reported in previous studies on Korean granites, but whose intercept values range from 16 to 43 and have a larger standard deviation than those of the present study. In conclusion, it would be advisable to estimate UCS from $I_{s(50)}$, considering the error range derived from the deviation of the regression equations.

• Korean Journal of Environment and Ecology
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• v.21 no.6
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• pp.544-553
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• 2007

This study is focused on the cultivation of seedlings and cuttings of roundleaf chastetree(Vitex rotundifolia L. f.) according to the sorts of soil and fertilization methods. The results are summarized as follows: When roundleaf chastetree seedlings(aged 1-0) and cuttings(aged 1-0) were cultivated in three different kinds of soil- sand, granite soil, and yellow silt- without any fertilization, 70% of the seedlings survived in sand and granite soil, and 35% did in yellow silt; 90% of the cuttings survived in granite soil and 80% did in sand and yellow silt. The general growth of both seedlings and cuttings was good in granite soil, and sand but relatively inferior in yellow silt. Seedlings showed good stem growth while cuttings had fine root growth. In case of cultivation of seedlings with different kinds and quantities of fertilizer adjusted and with granite soil as basic soil, seedlings and cuttings survived in the experimental section where only the organic fertilizer was used as basic fertilization; in contrast, seedlings grown in the experimental section were all dead where both inorganic and liquefied fertilizer were used. Cuttings showed considerably higher survival rates than seedlings at the experimental fertilization section; particularly, the survival rate of cuttings was twice as much as that of seedlings at the experimental section with low fertilization. This study results revealed that cuttings are desirable than seedlings in general rootage, growth, adaptability to soil, and cuttings have lower demand for soil fertility in time of growing roundleaf chastetree saplings.

• Journal of Ginseng Research
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• v.33 no.1
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• pp.13-25
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• 2009

Geochemical relationships between ginsengs and soils from three representative soil types, shale, phyllite and granite regions, from Keumsan were examined. High elements ere shown at the granite and shale areas of the weathered soils, the phyllite areas of he cultivated soils and the shale areas of the host rocks. T1 was enriched in ginsengs grown in the shale areas, Cs and B in the phyllite areas, and Be and Cd in the granite areas. Positive correlations were dominated by the shale areas. These relationships can be explained for mineral characteristics within the soils, and their behaviors related to the physio-chemical conditions. High elements were shown in the 2 year ginsengs of the hale areas, and 4 year ginsengs of the phyllite and granite areas in comparisons with ginsengs of the different ages from the same areas. These differences can be explained with ages of the ginsengs, solubilities of the minerals and physio-chemical differences within soils. The content differences of high elements such as Cs, T1 and Be were found between soils and ginsengs. Overall, these results suggest that components of ginsengs grown in the granite areas are chemically similar to the soils.

• Journal of the Korean earth science society
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• v.33 no.1
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• pp.73-81
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• 2012

The purpose of this study was to compare characteristics of students lived in volcanic region or not while observing the igneous rocks basalt and granite. For the study we recruited 68 fifth-grade students in Jeju Island, 29 fifthgrade students in Ulleung Island and 61 fifth-grade students in inland area area. This study was conducted as follows: After observing of granite and basalt, the students wrote observations. At the end of observation they also wrote all knowledges about granite and basalt except for the observations. The results are as follows: First, igneous rocks observations did not show a statistically significant difference between regional characteristics variables. Second, the amount of knowledge that students knew about granite and basalt except for the observation facts also did not show significant differences. Third, in the results of qualitative analysis for knowledges about granite and basalt except for the observation facts, many students knew about the igneous origin and about the substance but there were few statements that reflected the characteristics of the location. This results will provide a meaningful implication that the science class must consist of the use a various examples associated with a real-life.

• Journal of the Korean earth science society
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• v.22 no.1
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• pp.10-19
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• 2001

There are three scoria cones and their eruptive materials in Sarabong-Byeoldobong-Hwabukbong area Cheju Island. And they made complicated volcanic stratigraphy. In Byeoldobong tuff, basalt and granite xenoliths are present. It is presumed that the granite is a kind of basement of Cheju island. And Biseokgeori hawaiite has many kaersutite phenocrysts. Therefore, this area is very important for the study about history of volcanic activity of Cheju island. The lowest beds are Shinheung basalt and Byeoldobong tuff. Byeoldobong tuff has xenoliths of granite and phenocrystalline basalt. After the formation of these rocks, the Hwabukbong volcanism commenced. First of all this volcanism formed Biseokgeori hawaiite that has lots of kaersutite, a member of amphibole group, characteristically. Over this rock, Hwabukbong scoria cone was formed. The next Sarabong volcanism effused Keonipdong hawaiite that has lots of plagioclase and olivine phenocrysts and then Sarabong scoria cone was made up. Basalt xenolith in Byeoldobong tuff is different from Shinheungri basalt with regard to petrography, therefore this offers suggestion about existence of another basalt between basement and Shinheungri basalt. Granite xenolith derived from the basement of this area has features of the Jurassic granite in the Korea Peninsula, for example a lot of myrmekitic texture, microcline, and absolute age (172.4 Ma) by K-Ar method.

• Journal of the Korean earth science society
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• v.22 no.1
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• pp.1-9
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• 2001

Composition of the major and trace elements, Rb-Sr isochron age Sr-Nd isotope composition were determined for foliated in the Jeonju area, in the middle part of the Ogcheon Fold Bet, Korea. The geochemical characteristics of the Jeonju foliated granite indicate that the granite had been crystallized from a calc-alkaline series, and formed in a volcanic are environment. The isotopic compositions of the Jeonju foliated granite give Rb-Sr whole rock errorchron age of 168.2${\pm}$8 Ma(2${\sigma}$), corresponding to the middle Jurassic period, with the Sr initial ratio of 0.71354${\pm}$0.00031. $^{143}$Nd/$^{144}$Nd ratios, ${\varepsilon}$Nd and ${\varepsilon}$Sr values range from 0.511477 to 0.511744, -15.4${\sim}$-21.2, and +108.8${\sim}$+l42.6, respectively. Model ages were caculated to be 1.82${\sim}$2.89Ga. The isotopic data of Jeonju foliated granite indicate that the source material may have been derived from partial melting of continental crust materials.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.227-236
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• 2003

The evaluation of the reliable strength and deformation characteristics of weathered granite masses is very important for the design of geotechnical structure under working stress conditions. Various types of laboratory test such as triaxial compression test can be performed to determine the strength parameters. However, it is very difficult to obtain the representative undisturbed samples on the site and also the rock specimen cannot represent rock mass including discontinuities, fracture zone, etc. This study aims to investigate the strength and deformation characteristics of granite masses corresponding to its weathering and develop a practical strength parameter evaluation method using the results of PMT. To predict weathering intensity and strength parameters of the weathered granite masess in the field, various laboratory tests and in-situ tests including field triaxial test and PMT are carried out. Based on the results of weathering index tests, the classification method is proposed to identify the weathering degree in three groups for the weathered granite masses. Using the analytical method based on the Mohr-Coulomb failure criteria and the cavity expansion theory, the strength parameters of rock masses were evaluated from the results of PMT. It shows that weathering intensity increases with decreasing the strength parameters exponentially. The strength parameters evaluated with the results of PM almost coincide with the results of field triaxial test.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.6
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• pp.84-93
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• 2004

This study was carried out to select proper species for early stage replantation in granite forest roads cut-slope. From two to sixteen year elapsed forest roads in four regional areas of Gangwon-do, sample plots were selected, and their vegetations and environmental factors were investigated. Soil organic matter, total nitrogen, soil moisture content, and bulk density in the decomposed granite soils were below 1.32%, 0.08%, 10.0%, and above 1.24g/$cm^3$, respectively. The result indicated that the soil was not good for plant growth. The environmental factors affecting distribution of species in the granite forest roads were the elapsed year, cut-slope, elevation, and cut-slope aspect. Species with high frequency in the granite forest road cut-slope ordered Lespedeza bicolor, Rubus crataegifolius, Pinus densiflora, Lysimachia clethroides, Amorpha fruticosa, Dactylis glomerata, Lespedeza cyrtobotrya, Festuca arundinacea, Spodiopogon sibiricus, Artemisia stolonifera, and Weigela subsessilis. Herbs seeded in earth stage such as Dactylis glomerata, Lolium perenne, and Festuca arundinacea had changed into perennial herbs such as Carex lanceolata, Poa sphondylodes, Patrinia villosa, Artemisia princeps var. orientalis, Spodiopogon sibiricus, Melica onoei, Artemisia keiskeana, Artemisia stolonifera, Astilbe chinensis var. davidii, Spodiopogon sibiricus, and those had changed into shrubs such as Rubus crataegifolius and Weigela subsessilis, and those had changed into trees such as Salix hulteni, Salix koreensis, and Fraxinus rhyncholhylla according to elapsed year of forest roads. Legumes such as Lespedeza sp., Pueraria thunbergiana, Amorpha fruticosa, etc., herbs such as Artemisia keiskeana, Artemisia princeps var. orientalis, Artemisia stolonifera, Astilbe chinensis var. davidii, Spodiopogon sibiricus, Miscanthus sinensis, etc., and woody plants such as Pinus densiflora, Rubus crataegifolius, Weigela subsessilis, Zanthoxylum schinifolium, Rhododendron mucronulatum, etc., with foreign herbs were considered as proper species for replantation in granite forest road cut-slope.

• Korean Journal of Mineralogy and Petrology
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• v.33 no.3
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• pp.215-232
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• 2020

The study area of Nokjeonri in Yeongwol belongs to the Taebaeksan Mineralized District. Ca and Mg skarn and related ore mineralization are developed in the Pungchon formation along the contact with the Imog granite. Ca skarn hosted in limestone mostly comprises garnet and pyroxene. Mg skarn developed in dolomite includes olivine and serpentine. Magnetite-hematite and pyrrhotite(±scheelite)-pyritegalena-sphalerite were mineralized during early and late stage, respectively. Garnet compositions are dominated by andradite series in proximal area and grossular series in distal area. Pyroxene compositions correspond to diopside series in majority. These compositional changes indicate that the fluids varied from oxidizing condition to reducing condition due to increased reaction with carbonated wall rocks as the fluids moved from the granite to a distal place. Fe₂O₃ and MgO concentrations of magnetite are higher in Mg skarn than those in Ca skarn, while FeO shows opposite trend. The Zn/Fe ratio of sphalerite increases with distance from the Imog granite. The δ³⁴S values of sulfide minerals are similar to those of the Imog granite, indicating magmatic origin in ore sulfur. Mineralization was established in the order of skarn, oxide and sulfide minerals with decreasing temperature and oxygen fugacity and increasing sulfur fugacity.

• Economic and Environmental Geology
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• v.8 no.1
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• pp.25-56
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• 1975

Most fluorite deposits of South Korea are distributed in three metallogenic zones namly as: Hwacheon, Hwangangni and Geumsan metallogenic zones. Fluorite deposits of each zone show The characteristic features owing to the geological setting, the structural patterns and their forming processes. deposits of the Hwacheon metallogenic zone are wholly fissure filling hydrothermal veins emThe bedded in shear fractures of the granite gneiss or schists of Precambrian age or in the cooling fractures of the granite and acidic hypabyssal rocks which are assumed to be a differentiated sister rock of the granite. Localization of most fluorite veins of the region is structurally controlled by NW and EW fracture systems and genetically related to the granite intrusion which ascertained as motivating rock of the fluorite mineralization. Fluorites are in most cases accompanied by quartz, chalcedony mainly and rarely agate, calcite, barite and sulphide base metals in some localities. The deposits of the Hwangangni metallogenic zone were formed at the last stage of hydrothermal polymineralization of W, Mo, Cu, Pb, Zn. The majority of the fluorite ore bodies were originated from replacement in limestone beds of Great Limestone Series or in calcareous interbeds of metasediments, whereas some cavity-filling ore bodies were embedded in phyllites and schists of the Ockcheon system and along the fissures in the replaced beds which were originated by volume decrease. The localization of fluorite deposits in this region is genetically related to the Moongyong granite which has been dated as middle Cretaceous, and controlled structurally by the $N20^{\circ}{\sim}50^{\circ}W$ extension fracture system or axial planes of folds, and by faults of NE direction that acted as paths of ore solution. The deposits of the Geumsan metallogenic zone are seemed to be formed through the similar process as that of Hwangangni metallogenic zone, but characteristic distinctions are in that they are more prevailing fracture filling veins and large number of the deposits are localized in roof-pendants or xenolithes of limestone in granites and porphyries. Igneous rocks that presumably motivated the mineraltzation are middle Cretaceous Geumsan granite and porphyries. Metallogenic epoch of the fluorite mineralization of South Korea are puesumably limited in early-middle Cretaceous. Studies of the fluid inclusions in fluorites of the region reveal that the homogenization temperature of the fluorite deposits are as follows: Hwacheon metallogenic zone : $95^{\circ}C{\sim}165^{\circ}C$; Hwangangni metallogenic zone : $97^{\circ}C{\sim}235^{\circ}C$; Geumsan metallogenic zone : $93^{\circ}C{\sim}236^{\circ}C$. Judging from the above results, the deposits of the Hwancheon region were formed at the epithermal stage, and those in the Hwangangni and Geumsan regions, were deposited at epithermal stage preceded by mesothermal mineralization of small scale in which some sulphide minerals were deposited. The analytical data of minor elements in the fluorites reveal that ore solutions of Hwangangni metallogenic zone seemed to be emanated in more acidic stage of magma differentiation than Hwacheon metallogenic zone did.