• Economic and Environmental Geology
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• v.37 no.3
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• pp.291-301
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• 2004

In order to charaterize weathering of chalcopyrite and behavior of dissolved metal ions in waste rocks from Manjang Cu mine, mineralogical studies such as refractive microscope, XRD and SEM/EDS analyses carried out. The weathering was mainly occurred in fractures and edge of the chalcopyrite within the mine waste rocks. The weathering process can be seen to reflect four stages based on the weathering degree of chalcopyrite. The main secondary minerals are goethite, covellite, azurite, malachite and brochantite. Dissolved Cu and As were mainly adsorbed Fe-hydroxide. Poorly crystalline Fe-oxide contains relatively high As contents. In oxdizing condition, the weathering of chalcopyrite mainly occurs along the fracture, while the replacement of chalcopyrite observed mainly in the grain and produced covellite and brochantite. The dissolved metals (Cu, Fe, As) in waste rocks from the abandoned Manjang mine area could attenuate naturally by precipitation, adsorption and replacement reaction.

• 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.

• Economic and Environmental Geology
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• v.23 no.2
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• pp.201-213
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• 1990

Mineralogy, chemistry, physical property, and fossil abundance have been studied for the samples collected from three weathering profiles, two from the Duho Formation and one from the Hagjeon Formation in the Tertiary sediments in the Pohang area. The mineralogy of the samples from the Duho Formation shows somewhat different from that of the Hagjeon Formation. Kaolinite is more abundant and shows higher crystallinity in samples from the Duho Formation than those in the Hagjeon Formation, but clay mineral assemblage in each weathering profile remain fairly constant with depth. This difference in mineral distribution seems to be inherited from original source materials. It indicates that little or not severe leaching has been taking place in these three weathering profiles. Weathering indicies indicate different degrees of susceptibility to chemical weathering in these two formations. The Duho Formation has a higher degree of susceptibility to weathering than that of the Hagjeon Formation which is mainly due to differences in clay mineral assemblages in both formations. A noticeble colour difference between oxidized and unoxidized zones in each profile can be easily recognized which is definetely due to different decomposition rate organic carbon by various oxidation state from surface to bottom of the profile. Weathering process have also intensively influenced microfossil preservation about up to 7-10 m in depth in the Duho Formation. Consequently, characteristics observed at weathering surface should be used as a subsidiary tool in setting geologic boundary or establishing formation. Great care must be taken to choose sampling site for microfossil study.

• Journal of the Korean GEO-environmental Society
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• v.23 no.3
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• pp.15-22
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• 2022

This study aims to observe the swelling representative rocks in Korea and to suggest improvements in the use of test methods and prior analysis in relation to the weathering of rocks. The swelling test and analysis were performed on the drilling cores obtained for the ground investigation at the domestic highway construction site. For the method of determining the absorption expansion index of rocks, the method proposed in "Standard Methods for Sample Collection and Specimen Preparation" of ISRM and Korean Rock Engineers Standard Rock Test Method was used. The specimen for the measurement of the expansion displacement was cylindrical with a height of 10 cm and a diameter of 5 cm. The existing swelling analysis method evaluates the sensitivity to weathering by using the maximum expansion displacement, but since the classification by bedrock grade is unclear, it is reasonable to use the rate of change of the expansion displacement according to the immersion time. It is necessary to conduct an experiment to distinguish between weathering and fault deterioration. In addition, long-term weathering prediction technology for each cancer type is needed through the expansion displacement analysis of the chemical weathering stage.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.101-108
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• 2005

Because the stone cultural properties located outdoors, they have been altered and deteriorated in external appearance due to environmental factors such as acid rain, extreme change in temperature, and salts. Damage to stone cultural properties is accelerated particularly due to recent industrial development and environmental pollution. An experimental study was conducted to evaluate the effect of environmental contaminants on the weathering of granite. And as part of the developing of conservation method, $TiO_2$ catalyst was prepared and tested. When fresh granite was dipped into the salt and acid solutions, dissolution rate of eight minerals (Si, Mg, Ca, Na, K, Fe, Mn, Al) are abruptly increased at initial stage of reaction and then increased steadily until 100 cycles. After salt and acid solution experiments, the mineral compositions of the granite surface were lower then that of the fresh granite and density of the weathered granite was steadily decreased from $2.60\;g/cm^3$ to $2.56\;g/cm^3$, but Poissions ratio and absorption ratio were slightly increased. It was expected at stone cultural assets could be weathered by salts and acid rain. In the case of $TiO_2$ was coated to the granite, the dissolution rate of minerals and absorption ratio of $TiO_2$ coated granite were decreased. Therefore, the $TiO_2$ coating method tested in this study considered to be a viable method to assist in the conservation of stone cultural properties from environmental contaminants.

• Proceedings of the KSEEG Conference
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• 2000.04a
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• pp.128-131
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• 2000

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.484-486
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• 2004

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.11a
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• pp.141-146
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• 2005

• Proceedings of the KSEEG Conference
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• 2002.04a
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• pp.306-308
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• 2002

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.3
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• pp.141-147
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• 1998

This study was initiated to identify the general groundwater quality and the effects of heavy-metal enrichments in the black shales and coal materials in Dukpyung area. Groundwater quality could be divided into three groups based on the major weathering processes in the groundwater system; Group I of carbonate weathering, Group II of silicate weathering with the probable effects of acidic mine drainage, and Group III of silicate weathering with relatively high concentrations of chloride components in anions. Metal contamination of groundwater was not observed. Locally, however, acidic mine drainage appeared to be produced and recharged into the groundwater system. In addition, contamination by NO$_3$-N ranged 2 to 3 times higher than the drinking water standards, probably due to infiltration of domestic sewage and/or fertilizers into the shallow aquifer.