• Geophysics and Geophysical Exploration
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• v.24 no.3
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• pp.73-77
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• 2021

Induced polarization (IP) is useful for mineral exploration and hydrogeological studies by visualizing the electrochemical reactions at the interface between polarized minerals and groundwater. Frequency-domain IP (FDIP) is not actively applied to field surveys because it takes longer to acquire data, despite its higher data quality than conventional time-domain IP. However, data quality is more important in current mineral exploration as the targets gradually shift to deep or low-grade ore bodies. In addition, the measurement time reduced by automated instrumentation increases the potential for FDIP field applications. Therefore, we demonstrate that FDIP can detect mineral exploration targets by performing geophysical logging in the boreholes of a skarn deposit, in South Korea. Alternating current (AC) resistivity, percent frequency effect (PFE) and metal factor (MF) were calculated from impedance values obtained at two different frequencies. Skarn zones containing magnetite or pyrite showed relatively low AC resistivity, high PFE, and high MF compared to other zones. Therefore, FDIP surveys are considered to be useful for mineral exploration.

• Economic and Environmental Geology
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• v.51 no.6
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• pp.473-483
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• 2018

Green-blue coloured supergene minerals are covering host rocks along the gallery wall in the Gukjeon mine, a lead - zinc skarn deposit located in Miryang, Gyeongsangnam-do. These minerals have been described as azurite or malachite, but recent study recognized that the green minerals are devilline and blue minerals are Cu-Zn hydrated sulfates, but exact identification and detailed mineral characteristics are also not well known. In this study, we divide green-blue minerals into five groups (GJG) according to their external features and conducted XRD and SEM analyzes in order to identify mineral name and clarify the mineralogical characteristics. GJG-1, a bright bluish green group, consists of brochantite and quartz and GJG-2, a pale green colour with easily crumbly, of schulenbergite and a small amount of gypsum. Although pale blue GJG-3 and glassy lustrous bluish green GJG-4 have the same mineral assemblages with serpierite and gypsum in spite of different colour and luster, gypsum content may control the physical properties. GJG-5 with a gel phase mixture of pale blue and dark blue mineral is comprised of hydrowoodwardite, glaucocerinite, bechererite, serpierite and gypsum. The six green-blue minerals from the Gukjeon mine could be classified by Cu:Zn ratio, (Si + Al) content, Si:Al ratio, and Ca content. The physico-chemical environment of mineral formation is considered to be controlled by the geochemical factors in the surrounding fluid, and it looks forward that the accurate formation environment will be revealed through additional research. This paper gives greater mineralogical significance in the first report of several hydrated sulfate such as serpierite, glaucocerinite and bechererite in Korea. It has also rarely been reported the occurrence of several Cu-Zn hydrated sulfate in the same deposit in the world.

• Korean Journal of Mineralogy and Petrology
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• v.37 no.2
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• pp.77-85
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• 2024

Recently, the world has been declaring global carbon neutrality to curb carbon emissions, a major factor in global warming. Therfore, high-tech and clean energy industries such as renewable energy, electric vehicles, batteries, and semiconductors are rapidly developing. The Korean government selected total 33 critical minerals on based of evaluating the supply risk and economic impact of raw minerals essential for national high-tech industries (semiconductors, secondary battery, etc). Among these critical minerals, Copper, Zinc and lead have been used as basic materials in human life from the past to the present and in addition, they are currently used as an essential material for mobile phones, electric vehicles, and batteries. So, I would like to introduce the Las Bambas copper mine within Apurimac porphyry copper metallogenic belt of Peru, which have the world's 2^nd (copper), 4^th (zinc) and 5^th (lead) largest reserves of these critical minerals. Las Bambas copper mine is the world's largest mine with copper reserves of more than 1 billion tons and is joint venture project mine invested by MMG (Minerals and Metals Group, 62.5%), Guoxin international investment company (22.5%) and CITIC metal company (15.0%). This mine mainly produces copper and also produces gold, silver and molybdenum as a by-product. The ore grade of this mine has 0.77% Cu, 0.06 g/t Au, 3.93 g/t Ag and 178 ppm Mo. Mineral resource and ore reserve of this mine have 10.5 million ton Cu (0.61% Cu) and 6.9 million ton Cu (0.73% Cu). So, this mine life is about more than 20 years. The copper mineralization of this mine occurs as skarn type and vein type related with lower limestone of Ferrobamba formation and Cenozoic monzonites.