• Korean Journal of Plant Resources
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• v.20 no.1
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• pp.12-21
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• 2007

Ginsengs (1,2 3 years) from the Keumsan are analysed for the inorganic compounds and compared with the their soils from the granite, phyllite and shale areas. In the soils, the granite areas show high $Al_2O_3\;and\;Na_2O$ contents while the phyllite areas have high $Fe_2O_3,\;MnO\;and\;MgO$ contents. Positive correlations are shown in the $Al_2O_3-K_2O\;and\;Fe_2O_3-MgO$ pairs while negative correlations are shown in the $SiO_2-CaO$ pair. In the ginsengs, the shale areas are high in the most of the elements, but low in the granite areas. Compared with same soils of different ages, Al, Na and Ti contents of the ginsengs are high in the all areas. The shale areas are mainly high in the upper parts while the granite areas are mainly high in the root parts. Regardless of the localities, Fe, Mn and Ca contents are high in the upper parts while Ti contents are high in the root parts with differences of several times. Relative ratios between field soils and ginsengs (field soil/ginseng) suggest that the ginsengs show high Ca contents with differences of several ten times whereas the soils have high Na, Fe, Ti and Al contents with differences of several times. Regardless of the localities, the ratios of the Al, Mn and Na are high in the 2 year relative to the 3 year. Overall ratios between field soils and ginsengs are mainly big in the 2 year area relative to the 3 year area. It suggests that contents of the 3 year ginsengs are more similar to those of their soils relative to the 2 year and the ginsengs may absorpt eligible element contents with increasing ages.

• Journal of Conservation Science
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• v.23
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• pp.11-24
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• 2008

A physical characteristics and chemical compositions change by weathering on the granite were examined for the conservation treatment of the Mireuksaji temple stone pagoda. The natural weathered granite was collected from the Mt. Mireuk, and divided into the classification standards based on weathering degrees and strength measured by rock-test hammer. The results from comparison of the strength measured by undestructive rock-test hammer and the strength values converted from ultrasonic velocity showed that each strength measurement value was proportionate. The water absorption of the sample was 1.68 to 0.20%. The F-type of fresh rock was not naturally saturated and the WW-type was naturally saturated but took quite a long time. The water absorption was increased gradually in order of SW-type, the MW-type and the HW-type according to weathering condition. The CW-type samples showed the highest water absorption among the weathered classification samples. Through dyeing test, it was found out that only the feldspar was dyed out of the F-type and the WW-type. The SW-type and the MW-type were distinguished by the fact that plagioclase being dyed. And dyed area was expanded to quartz crack in HW-type and CW-type. Physical change by weathering of the rock-forming minerals could be classified with 3 grades. Through the XRD analysis, albite among the rock-forming mineral showed remarkable decrease. SEM-EDX analysis of the component change in the rock-forming minerals such as biotite, plagioclase, and orthoclase, showed that in case of highly-weathered grade samples compared with fresh samples, contents of the $Al_2O_3$, $K_2O$, $Na_2O$ increase and CaO, MgO decrease in the biotite, the CaO, $K_2O$ increase and $Na_2O$ decrease in the plagioclase, the $Al_2O_3$ a little increase and $K_2O$, $Na_2O$ decrease in the orthoclase. The results of extracted cation analysis using the powder samples of each weathering grade, the CaO, $Na_2O$, $K_2O$ and MgO are highly chemical variations in rock forming minerals and positive variation show high in the weathering grade of the WW-type and CW-type. This research will be used as an importance data to establish a plan for conservation treatment of composed stone in the Mireuksaji temple stone pagoda.

• Economic and Environmental Geology
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• v.50 no.6
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• pp.487-495
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• 2017

A granite rock body, called 'Bukbawi', located on a mountaineering trail at Mt. Palgong Provincial Park is popular among the public because it resembles a percussion instrument. If someone hits the specific surface area of this rock body, people can hear drum-like sound. Such phenomenon may be geologically associated with exfoliation process of the granite body or miarolitic cavity developed after gasses escaped during formation of granite. To understand better the inner structure causing drum-like sound, we carried out a non-destructive ground-penetrating radar survey. In this study, as our primary target is very close to the surface, we utilized 1 GHz antennas to produce high-resolution near-surface images. In order to construct 3-D internal images, the measurements were conducted along a pre-defined grid. The processed radargrams revealed that the locations associated with 'drum' sound coincide with strong reflections. In addition, both reflection patterns of fracture and cavity were observed. To further quantify the observed reflections, we simulated GPR scans from a synthetic fracture in a granite body, filled with different materials. The simulated results suggest that both exfoliation process and miarolitic cavity may have contributed to the 'drum' phenomena. Furthermore, the radargrams showed a well-developed cavity signature where two major reflection planes were crossed. Thus, our study is an example of non-destructive geophysical studies that can promote Earth Science in the broader community by examining geological structures attracting the public.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.359-371
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• 2006

In this study, the soil characteristics are analyzed using the result of various soil tests as an object of the soil layer of natural slopes in landslides areas composed with gneiss, granite, and the tertiary sedimentary rock. To investigate the soil characteristics according to landslide and non landslide areas, soils are sampled from Jangheung, Sangju and Pohang. The landslides at three areas are occurred due to heavy rainfall in same time. The geology of Jangheung area, Sangju area and Pohang area is gneiss, granite, and the tertiary sedimentary rock, respectively. On the basis of the landslide data and the result of soil test, the soil characteristics at the landslide area and the differentiation between landslide area and non landslide area are analyzed. However soil characteristics have a little differentiation to geological condition, the uniformity coefficient and the coefficient of gradation of soils at the landslide area is larger than those of soils at the non landslide area. Also, the proportion of fine particle of soils at the landslide area is higher. The plastic limit of soils sampled from the granite and the sedimentary rock regions is larger than that sampled from the gneiss region. However the liquid limit is irrelevant to the geological condition. Also, the consistency of soils at the landslide area is smaller. The natural moisture content of soils in the sedimentary rock regions is larger than that of the granite and gneiss. It is mainly influenced by mineral composition, soil layer structure, weathering condition, and so on. The soils sampled from landslide area have higher porosity and lower density than those from non landslide area. It means that the soils of landslide area have poor particle size distribution and loose density. Therefore, the terrain slope with poor distribution and loose density is vulnerable to occur in landslides. Also, landslides are occurred in the terrain slope with high permeability. The permeability is mainly influenced by the soil characteristics such as particle size distribution, porosity, particle structure, and the geological origins such as weathering, sedimentary environment. Meanwhile, the shear strength of soils is little difference according to the geological condition. But, the internal friction angle of soils sampled from the landslide area is lower than that of soils from the non landslide area. Therefore, the terrain slope with low internal friction angle is more vulnerable to the landslide.

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.557-576
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• 2015

Groundwaters in granite, gneiss, and two-mica granite formations, including faults, in the Hoengseong area are examined to determine the relationship between their uranium and radon-222 contents and rock types. The chemical compositions of 38 groundwater samples and four surface water samples collected in the study area were analyzed. Sixteen of the samples showing high uranium and radon-222 contents were repeatedly analyzed. Surface radioactivities were measured at 30 points. The uranium and radon-222 concentrations in the groundwater samples were in the ranges of 0.02-49.3 μg/L and 20-906 Bq/L, respectively. Four samples for uranium and 35 samples for radon had concentrations exceeding the alternative maximum contaminant level of the US EPA. The chemical compositions of groundwaters indicated Ca(Na)-HCO₃ and Ca(Na)-NO₃(HCO₃+Cl) types. The pH values ranged from 5.71 to 8.66. High uranium and radon-222 contents in the groundwaters occurred mainly at the boundary between granite and gneiss, and in the granite area. The occurrence of uranium did not show any distinct relationship to that of radon-222. The radon-222, an inert gas, appeared to be dissolved in the groundwater of the aquifer after wide diffusion along rock fractures, having been derived from the decay of uranium in underground rocks. The results in this study indicate that groundwater of neutral or weakly alkaline pH, under oxidizing conditions and with a high bicarbonate content is favorable for the dissolution of uranium and uranium complexes such as uranyl or uranyl-carbonate.

• Economic and Environmental Geology
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• v.30 no.4
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• pp.289-301
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• 1997

The Boguk cobalt mine is located within the Cretaceous Gyeongsang Sedimentary Basin. Major ore minerals including cobalt-bearing minerals (loellingite, cobaltite, and glaucodot) and Co-bearing arsenopyrite occur together with base-metal sulfides (pyrrhotite, chalcopyrite, pyrite, sphalerite, etc.) and minor amounts of oxides (magnetite and hematite) within fracture-filling $quartz{\pm}actinolite{\pm}carbonate$ veins. These veins are developed within an epicrustal micrographic granite stock which intrudes the Konchonri Formation (mainly of shale). Radiometric date of the granite (85.98 Ma) indicates a Late Cretaceous age for granite emplacement and associated cobalt mineralization. The vein mineralogy is relatively complex and changes with time: cobalt-bearing minerals with actinolite, carbonates, and quartz gangues (stages I and II) ${\rightarrow}$ base-metal sulfides, gold, and Fe oxides with quartz gangues (stage III) ${\rightarrow}$ barren carbonates (stages IV and V). The common occurrence of high-temperature minerals (cobalt-bearing minerals, molybdenite and actinolite) with low-temperature minerals (base-metal sulfides, gold and carbonates) in veins indicates a xenothermal condition of the hydrothermal mineralization. High enrichment of Co in the granite (avg. 50.90 ppm) indicates the magmatic hydrothermal derivation of cobalt from this cooling granite stock, whereas higher amounts of Cu and Zn in the Konchonri Formation shale suggest their derivations largely from shale. The decrease in temperature of hydrothermal fluids with a concomitant increase in fugacity of oxygen with time (for cobalt deposition in stages I and II, $T=560^{\circ}C-390^{\circ}C$ and log $fO_2=$ >-32.7 to -30.7 atm at $350^{\circ}C$; for base-metal sulfide deposition in stage III, $T=380^{\circ}-345^{\circ}C$ and log $fO_2={\geq}-30.7$ atm at $350^{\circ}C$) indicates a transition of the hydrothermal system from a magmatic-water domination toward a less-evolved meteoric-water domination. Sulfur isotope data of stage II sulfide minerals evidence that early, Co-bearing hydrothermal fluids derived originally from an igneous source with a ${\delta}^{34}S_{{\Sigma}S}$ value near 3 to 5‰. The remarkable increase in ${\delta}^{34}S_{H2S}$ values of hydrothermal fluids with time from cobalt deposition in stage II (3-5‰) to base-metal sulfide deposition in stage III (up to about 20‰) also indicates the change of the hydrothermal system toward the meteoric water domination, which resulted in the leaching-out and concentration of isotopically heavier sulfur (sedimentary sulfates), base metals (Cu, Zn, etc.) and gold from surrounding sedimentary rocks during the huge, meteoric water circulation. We suggest that without the formation of the later, meteoric water circulation extensively through surrounding sedimentary rocks the Boguk cobalt deposits would be simple veins only with actinolite + quartz + cobalt-bearing minerals. Furthermore, the formation of the meteoric water circulation after the culmination of a magmatic hydrothermal system resulted in the common occurrence of high-temperature minerals with later, lower-temperature minerals, resulting in a xenothermal feature of the mineralization.

• Korean Journal of Remote Sensing
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• v.7 no.2
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• pp.95-111
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• 1991

The study is to analyze and interpret lineaments and circular/arc structures on the Landsat TM images which cover the Korean peninsula and the attched islands except the Ulneung island. The Landsat TM images which cover the Korean territory are 23 scenes, and band 3 and band 5 were selected for the study from seven bands, because the both vands are sensitive on soil moisture and geological materials. Lineament trend analysis Sinian direction (NNE-SSW), Pyeongan direction(NW-SE), Yodong direction(NE-SW), Korean direction(NNW-SSE) and Danyang direction (WNW-ESE) are predominant lineament trands of Korea. Circular/arc structures can be devided into four categories according to their origin; 1) volcanic activity origin, 2) granite intrusion oringin, 3) structural origin and 4) the others.

• Journal of the Korean earth science society
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• v.42 no.5
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• pp.556-570
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• 2021

This study presents the data analysis results of groundwater chemistry and the occurrence of fluoride in groundwater obtained from the groundwater quality monitoring network of Korea. The groundwater data were collected from the National Groundwater Information Center and censored for erratic values and charge balance (±10%). From the geochemical graphs and various ionic ratios, it was observed that the Ca-HCO₃ type was predominant in Korean groundwater. In addition, water-rock interaction was identified as a key chemical process controlling groundwater chemistry, while precipitation and evaporation were found to be less important. According to a non-parametric trend test, at p=0.05, the concentration of fluoride in groundwater did not increase significantly and only 4.3% of the total groundwater exceeded the Korean drinking water standard of 1.5 mg/L. However, student t-tests revealed that the fluoride concentrations were closely associated with the lithologies of tuff, granite porphyry, and metamorphic rocks showing distinctively high levels. This study enhances our understanding of groundwater chemical composition and major controlling factors of fluoride occurrence and distribution in Korean groundwater.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.97-104
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• 2001

The magnitude and the orientation of in-situ stresses contribute to ground displacement and stresses in the field of underground space. This paper investigates in-situ stresses at various depth on the basis of 392 data which were determined by over-coring and hydro-fracturing test methods in the Korea peninsula. The result shows that in-situ stress distribution are more or less non-uniform through the Granite and Gneiss sub-area, and that the K-value in the Volcanic sub-area are below 1 at the deep depth. Also, the result of three dimensional numerical analyses of tunnel shows that the direction and magnitude of displacement around tunnel are much effected by the stress difference between the maximum and the minimum horizontal stress.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.202-212
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• 1992

This study reports on the genesis and mineralogical characteristics of the clay minerals in the soils derived from the five major parent rocks of granite, granite-gneiss, limestone, shale, and basalt in Korea. The investigation on the mineralogical aspects of primary and secondary minerals of the rocks and coarse fractions in the soils have been already reported. In this report, the identification of clay minerals in the soil clay fractions was done through the analyses of chemical, X-ray diffraction, and thermal methods. The studies showed clearly that much of the clay minerals was evolved by the weathering of primary minerals and some were further developed by the transformation of secondary minerals. Cation exchange capacity(CEC) of the clay fractions increased with higher amotunts of vermiculite, chlorite, and illite, however, decreased with higher hydroxy octahedral sheet within the interlayer spaces of vermiculite even if dominant clay with vermiculite. Feldspars in the granite and granite-gneiss might be completely transformed to kaolin mineral, Illite, chlolrite, and vermiculite formed by the alteration of micas, amphibole, augite, and primary chlorile seem to be subsequently transformed to the mixed layer minerals such as illite/vermiculite, illite/chlorite, and chlorite/vermiculite. These weathering products may be ultimately transformed into kaolin minerals. The smectite minerals in the clay fractions of the soils developed on the limestone are considerably present and they seem to be formed directly by the precipitation from high Mg solution and/or by the transformation of vermiculite from micas and chlorite in the parent materials. Abundant presence of illite in the soil clays developed on the shale is considered to have inherited from the fine particles and more resistant hydrous muscovite. The weathering sequences of the hydrous muscovite were as follows according to the degree of soil development ; hydrous muscovite ${\rightarrow}$ illite/vermiculite mixed layer(Inceptisols, Daegu series) and hydrous muscovite ${\rightarrow}$ illite/vermiculite mixed layer ${\rightarrow}$ vermiculite ${\rightarrow}$ kaolin mineral(Alfisols, Buyeo series). The plagioclase in the basalt might be mostly weathered to kaolin minerais. The augite in the basalt is likely to be transformed through progressive stage of weathering, augite ${\rightarrow}$ chlorite ${\rightarrow}$ chlorote/vermiculite mixed layer ${\rightarrow}$ vermiculite ${\rightarrow}$ kaolin. Another weathering sequence of augite could be expected, augite ${\rightarrow}$ chlorite ${\rightarrow}$ illite by the presence of illite and illite/vermiculite mixed layer in the clay fractions. Vermiculite and gibbsite were quantified from thermogravimetry(TG) and kaolin minerals, from both TG and differerential thermal analysis (DTA). Vermiculite in Jangseong series from the limestone was the dominant clay mineral of 21.7 percent and had a range in the order of 9.2 percent in Buyeo series to 5.4 percent in Daegu series from the shale. The rest soils ranged from 8.8 to 28.3 percent. Kaolin minerals were the dominant clay mineral of 32.7 percent in Asan series from the granite-gneiss and Gueom series of 32.0 percent from the basalt. The soils from the limestone ranged from 9.4 to 14.9 percent. The rest soils ranged from 8.9 to 28.6 percent. Gibbsite were 3.9 and 2.3 percent for Weoljeong and Chahang series from the granite, respectively. In Asan and Cheongsan series from the giranite-gneiss were 1.4 and 4.5 percent, respectively, and 3.6 percent in Jangpa series from the basalt.