• Ocean and Polar Research
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• v.23 no.1
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• pp.11-21
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• 2001

K-Ar ages of the altered rocks from the Barton Peninsula are belows; altered tuffaceous andesite from southwestern part is 42 Ma, altered rocks contacted with quartz vein from southern part are 28 and 33 Ma, and advanced argillic altered andesite from northeastern part are 33 and 35 Ma. Those K-Ar ages are 10 My younger than granitic rocks of the Barton Peninsula. Hydothermal alteration of the Barton Peninsula was originated from mixing of magmatic water from parent magma of granitic rocks with meteoric water. The Al content in the hostrock is relatively constant during hydrothermal alteration, on the contrary the Mg content is in proportion to total alkali. The variation of total alkali and Mg contents in hydrothermal alteration indicates that those elements was washed out during hydrothermal alteration. The sequences of hydrothermal alteration of the Barton Peninsula is chloritization of amphiboles, sericitization of feldspars and kaolitization of sericite.

• 보존과학연구
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• s.26
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• pp.103-126
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• 2005

Coprostanol is a metabolic product of cholesterol, formed by microbial action in the mammalian gut. This chemical compound is the major sterol in human and has been routinely studied as a biomarker of sewage pollution in marine and lacustrinesediments. This has led to the search for coprostanol as a biomarker in archaeologicalsoils, in order to detect the presence of fecal material. In this study, five samples of archaeological soils excavated at Wanggung ri, Iksancity, were used to assess the possibility of using coprostanol as indicators of ancient human activity in archaeological areas. The sampled soils were analyzed MXRD,EDXRF for their physical and chemical properties. And coprostanol was analysed byGC/MSD, using SIM method to detect and quantify specific compound. The results showed the soils were composed of quartz and feldspars, inorganicelement such as $SiO_2$, $Al_2O_3$, $Fe_2O_3$ etc. Moreover, the result from the analysis wasindicated that the specific compound is coprostanol. The coprostanol was determined at $0.16~1.01\mug$/g in the range of concentrations. This finding indicate that clear promise exists for the exploitation of coprostanol as biomarker of ancient human activity inarchaeological survey. Therefore such studies can serve to increase the confidence we place on biomarker-based methodologies for assessing fecal pollution. The application of this methodology has proved a simple and effective way of searching for that pattern in successively more aged deposits either known or suspected to contain fecal material. And the more scientific analysis of the soils will be showed to utility of the area ancient dietary life style, ancient environment.

• Journal of Conservation Science
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• v.8 no.1 s.11
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• pp.1-9
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• 1999

The present aspect of the Seoggulam is the result of natural weathering of the rocks and influences by mankind. The rocks constituting the Seoggulam is granodiorite of medium and coarse grains which show brown to dark brown weathered surface resulted mainly from chemical weathering of feldspars. It also shows partly milky white or black colors due to influences by weathering products of cement used in the concrete dome and cracks. There are cracks and crack zones with very small cracks which may be formed by strong weathering and influences of shocks during operations of reconstitution and repair. However, for the better conservation, it must be considered to maintain the balances of temperature and moisture, especially relative moisture in places within the room, structural stability, and the influences of vibration made up by some reasons.

• The Journal of Engineering Geology
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• v.14 no.4 s.41
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• pp.381-390
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• 2004

This study was performed to relate the weathering properties of Oyaish tuff from Japan to mechanical properties of rocks in terms of mineralogical alteration and chemistry. The tuff is composed of clinoptilolite, quartz, feldspars, mordenite, opal C-T, and smectite. Since fresh tuff contains approximately $30\~50\%$ zeolite, it is expected that the rock is subjected to weathering process ascribed to water contents on earth surface, significantly reducing mechanical strength of tuff. It is also anticipated that weathering process and properties may be different even in the same rock mass, due to the differences in local mineralogy, chemistry and microtextures in tuff.

• Journal of the Mineralogical Society of Korea
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• v.13 no.3
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• pp.147-163
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• 2000

The mineralogy and chemical composition of reddish to brownish yellow residual soils, so called "Hwangto" have been examined according to representative host rocks. The result of the study indicates that Hwangto consists of 40-80% clay minerals and various minerals such as quartz, feldspar, hornblende, goethite, and gibbsite. Clay minerals include kaolinite, halloysite, illite, hydroxy interlayered vermiculite (HIV), mica/vermiculite interstratifield mineral and chlorite. The mineralogical constituents and contents of Hwangto were different depending on the types of host rocks. Moreover, the Jurassic granitic rocks contain relatively more kaolin minerals, whereas the Cretaceous granitic rocks contain more HIV and illite. In addition, reddish Hwangto contains relatively more kaolinite and HIV, and yellowish Hwangto contains more illite and halloysite. It is suggested that feldspars and micas of host rocks were chemically weathered into illite, halloysite, illite/vermiculite interstratified minerals, and HIV, and finally into kaolinite. Compared with their host rocks, the major chemical compositions of Hwangto tend to contain more $Al_2O_3,\;Fe_2O_3,\;H_2O$ in amount and less Ca, Mg, and Na. Hwangto contains relatively high amount of trace elements, P, S, Zr, Sr, Ba, Rb, and Ce including considerable amount of Li, V, Cr, Zn, Co, Ni, Cu, Y, Nb, La, Nd, Pb, Th in excess of 10 ppm. Relatively high amount of most trace elements were detected in the Hwangto. The major and minor chemical compositions of the Hwangto were different depending on the types of host rocks. However, their difference was in the similar range compared with the compositions of host rocks.

• Journal of the Mineralogical Society of Korea
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• v.22 no.2
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• pp.115-127
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• 2009

Mineral quantification was performed on sediments of the Ulleung basin by X-ray powder diffraction and the computer software based on Rietveld quantification method. The sediments are dominated by amorphous opal-A with quartz, feldspars, micas, clays, calcite, and pyrite. The opal-A shows iterative variation in abundance with increasing burial depth. In addition, the relative abundance of opal-A is coincident with abundance of organic carbon contents, indicating that the Ulleung sediment consists mostly of amorphous silica derived from organism in the pelagic environment. Upward increase in the abundance of opal-A is markedly shown in the cores located in the slope region. On the other hand, there is a distinct tendency that the abundance of calcite is inversely proportional to that of opal-A. This indicates that the abundance of opal-A increases during the rise of sea level. Also, the fall of sea level lowers the abundance of opal-A.

• Journal of Conservation Science
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• v.5 no.1 s.5
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• pp.41-68
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• 1996

Stone-cultural-properties, distributed In the area, have been investigated and studied on the characteristics and the rock phases in the geological and conservational point of view. Stone-Buddhas in the area can be subdivided into Maebul-, General -, and Massive rock-types according to their styles. The rocks used in these stone-cultural-properties are mainly massive, coarse grained biotite granite of the Jurassic age, which is widely distributed around the Reckon-gun area. However, quartz-feldspathic banded gneiss, marble, phyllite and hornblendite are also used. These rocks are mainly distributed in the Yongin-gun area. This suggests that the rocks used. These rocks are strongly influenced by chemical weathering so that the rock surface is very irregular with $2\~3mm$ relief. Biotite granite used shows generally weathered surface of brown color due to chemical weathering of feldspars. Moss are pervasive partly on the surface to show black and/or green colors. The strong weathering may induce secondarily to appear the igneous lineation, onion-structure, and/or minor cracks latent in the rocks. The cultural properties In the area are relatively well conserved except Maebuls and one(Duchangri 3-story) pagoda. However, one stone-buddha may be grinded recently by machine to take off the weathered surface resulting in the loss of its age and the original detailed shape. For conservation, they must be scientifically considered on the shape, kind of the rock phase and characteristics of the weathered phenomena.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.4
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• pp.203-209
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• 1998

The quality of groundwater used for natural mineral water should be strictly regulated on international level by hydrogeology experts and officials because groundwater is greatly subjected to contaminations and its aquifer system may be easily destroyed by external reasons. A total of 18 natural mineral water plants exist in Precambrian metamorphic terrains of the Gyunggi massif and Yeungam massif. The g개undwater quality for the natural mineral water investigated in hydrochemical aspects shows that pH ranges from 6.85 to 8.02 with an average of 7.52. The electric conductivity (EC) and hardness average 134.1 $\mu$S/cm and 43.5, respectively, which are relatively low to the total average (151.4 $\mu$S/cm and 57.9). The contents of major cations and anions are in the order of $Ca^{2＋}$＞$Na^{＋}$＞Mg$^{2＋}$＞K$^{＋}$ and HCO$_3$$^{-}$ ＞SO$_4$$^{2－}$ ＞Cl$^{-}$ ＞F$^{-}$ , respectively. The dominant water types determined by Piper diagram are $Ca^{2＋}$－$Na^{＋}$－HCO$^{-}$ $_3$and $Ca^{2＋}$-HCO$^{-}$ $_3$, mainly due to the dissolution of plagioclase in the host rocks. Representative correlation coefficients between chemical species are $Ca^{2＋}$－HCO$^{-}$ $_3$(0.92), $Ca^{2＋}$－Cl$^{-}$ (0.63), $Na^{＋}$－F$^{-}$ (0.67), HCO$^{-}$ $_3$－Cl$^{-}$ (0.66), and $Na^{＋}$－HCO$^{-}$ $_3$(0.63). The determinative. coefficients between $Ca^{2＋}$ and HCO$^{-}$ $_3$, and (Ca$^{2＋}$＋$Na^{＋}$＋K$^{＋}$ and EC art highest among the elements. According to the saturation index, most chemical species are undersaturated with respect to major minerals, except for some silica phases. In viewpoint of phase equilibrium, the chemical evolution of the groundwater may continue to proceed with increasing pH because the groundwater is undersaturated with respect to feldspars.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.83-92
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• 2005

Dissolution rate of minerals may differ from climates configuration, but weathering rate of feldspars is generally proved to be relatively higher The result of geochemical reaction modeling indicates the acid water of pH 4.5 excluding any other variables, was 2.3 times higher than that in ordinary rain of pH 5.7. This result proved that pH is very important factor in preservation of granite cultural properties. To prevent the weathering of stone cultural properties, weathering characteristics of stones should be studied first and constitution of dry environments, using water repellent or oil coating, isolating water which cause chemical weathering reaction like hydration and oxidization should be considered. Considering the long-term reactions between granite and rain, selection of materials, which can bring neutralization and non-oxidization conditions, are very important in using cleaning agents and biological controls.

• Economic and Environmental Geology
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• v.30 no.4
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• pp.327-340
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• 1997

Geochemical characteristics of groundwater, based on chemical analyses of 54 water samples, differ among main rocks of Haman formation, Panyawoel formation, andesite and granite in Daegu area in relation to mineralogical and chemical compositions of the rocks. Concentrations of most solutes are higher in groundwaters of Haman and Panyawoel formations than in those of andesite and granite. High concentrations of $Ca^{2+}$ and $Mg^{2+}$ in groundwaters of the sedimentary rocks result mainly from reaction of $CO_2$-charged water with calcite and weathered feldspars. Average groundwaters in the sedimentary rocks are oversaturated with respect to calcite. Major types of groundwaters are hard $Ca(HCO_3)_2$ and $CaSO_2-CaCl_2$ with hardness of 442 mg/l for Haman formation and 275 mg/l for Panyawoel formation whereas they are soft $Ca(HCO_3)_2$ with hardness 35 mg/I for andesite and 39 mg/I for granite. $Ca(HCO_3)_2$ type results mainly from calcite-dissolution and $CaSO_4-CaCl_2$ from pyrite and partly from domestic pollutants. $CaSO_4-CaCl_2$ type may indicate that groundwaters in the sedimentary rocks are more evolved geochemically than those in the igneous rocks, but it is not obvious because the type might be affected by pyrie dissolution and domestic pollutions. Acid rain is buffered by active calcite in the sedimentary rocks. In the igneous rocks acid rain might react with gibbsite and other forms of $Al(OH)_3$ that might have accumulated as weathering products of primary silicates, and is buffered.