• Economic and Environmental Geology
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• v.50 no.4
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• pp.313-324
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• 2017

Tsogttsetsii area, an intrusive complex associated with Cu mineralization, is located in the South Gobi, Mongolia. We performed the cross geochemical and extended exploration survey in Tsogttsetsii area. Cu mineralization in Tsogttsetsii area is porphyry Cu type related with alkali granite intruded in Late Carboniferous to Early Permian. In the concentrated occurring to malachite appears extensively prophylitic alteration zone having a chlorite and epidote. As results of the survey, Cu contents of potable XRF and of chemical composition for altered rocks ranges 1.08 to 18.3% in the 30 points and 1.08 to 32.9% in the 13 points, respectively. Ore minerals identified in XRD analysis and polarizing microscope that samples of copper oxides were composed mainly of malachite, azurite, permingeatite and cuprite and the other minerals are pyrite, chalcopyrite, pyrargyrite, dickite, calcite, chlorite and epidote. Mineralization can be considered occurring to selectively some granite of the surrounding aplite and faults in the only upper part coming up the hydrothermal solution of the remaining residual magma after the aplite intrusion.

• Environmental Engineering Research
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• v.20 no.1
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• pp.89-97
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• 2015

Remediation of wastewater contaminated with metal(II)-complexed species (Cu(II)-NTA (NTA: nitrilotriacetic acid), Cu(II)-EDTA (EDTA: ethylenediamine tetraacetic acid) and Cd(II)-EDTA is attempted using the potential applicability of ferrate(VI). Kinetics of pollutant degradation is obtained with the removal of ferrate(VI) studied at wide range of pH (8.0-10.0) and the concentration of metal(II)-complexed species (0.3 to 15.0 mmol/L) employing a constant dose of ferrate(VI) i.e., 1.0 mmol/L. Pseudo-first-order and pseudo-second-order rate constants were obtained in the reduction of ferrate(VI) which was then employed to obtain the overall rate constants of the pollutant degradation. The mineralization of NTA and EDTA was obtained with the change in TOC (total organic carbon) values collected by the ferrate(VI) treated pollutant samples. Decrease in pH and molar pollutant concentrations was greatly favored the percent mineralization of NTA or EDTA by the ferrate(VI) treatment. The treated pollutant samples were filtered and subjected for AAS (atomic absorption spectrophotometric) analysis to assess the simultaneous removal of copper and cadmium from aqueous solutions at the studied pH as well at the elevated pH 12.0. Results show that an enhanced removal of cadmium or copper was achieved at pH 12.0. Overall, ferrate(VI) possesses multifunctional application in wastewater treatment as it oxidizes the degradable impurities and removes metallic impurities by coagulation process.

• Economic and Environmental Geology
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• v.24 no.2
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• pp.151-165
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• 1991

The Au-Ag deposits of the Euiseong area occurred in quartz veins which filled fissures in Cretaceous sedimentary and volcanic rocks. These ore veins can be classified in two types of deposits based on metallic mineral assemblages as follow: a pyrite type gold-silver deposit (Hoedong mine), characterized by Cu sulfides with Au-Ag alloy, and a Sb-rich silver deposit (Keumdongdo mine), characterized by base metal with Ag-bearing sulfosalts. Mineralogic and fluid inclusion evidences suggest that the ore minerals of these deposits was deposited from initial high temperatures (near $350^{\circ}C$) to later lower temperatures ($200^{\circ}C$) with moderate salinity fluids ranging from 5.8 to 3.8 eq. wt. % NaCl. The gold-silver mineralization of the Hoedong mine occurred at temperatures between 300 and $200^{\circ}C$ from fluids with log $f_{s_2}$ of -10 ~ -16 atm. The antimony - silver mineralization of the Keumdongdo mine were deposited at the higher temperatures (350 to $250^{\circ}C$) and $f_{S_2}$ (-10 ~ -13 atm) than gold mineralization of the Hoedong mine. The calculated log f02 of fluids at $250^{\circ}C$ in two deposits are -32 to -34 atm and -36.5 to -38.5 atm, respectively. Boiling evidences indicate that the ore mineralization of the Hoedong mine occurred at more shallow depth (0.5km) than that (1km) of the Keumdongdo mine. The above differences of depositional environments between two deposits caused the compositional changes of ore minerals such as electrum and sphalerite.

• Journal of the Mineralogical Society of Korea
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• v.20 no.1 s.51
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• pp.35-46
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• 2007

Shinyemi skarn deposits occur as Fe-Mo skarn type and Pb-Zn-Cu hydrothermal replacement type along the contact between Cretaceous Shinyemi granitoids and Cambro-Ordovician mixed limestone and dolostone sequence of the Choseon Supergroup. In the lower part of Western Shinyemi ore body two stages of skarn formation have been observed: the early, stage I (magnesian) skarn with Fe mineralization and the late, stage II(calcic) skarn with Mo mineralization. The stage I skarn spatially is overprinted by stage II skarn. The stage I skarn is predominantly composed of olivine, magnetite and diopside whereas, the stage II skarn is dominated by hedenbergite and garnet. The skarnification process occurred in two stages, both prograde and retrograde for stage I and stage II skarns. In stage I, the prograde skarns, mainly composed of anhydrous silicate minerals, were formed at relatively higher temperatures (about $400\;to\;550^{\circ}C$) under low $CO_{2}$ fugacity ($X_{CO2}<0.1$) conditions. On the other hand, the retrograde skarns that consisted of hydrous minerals were formed at lower temperatures (about $300\;to\;400^{\circ}C$).

• Economic and Environmental Geology
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• v.52 no.5
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• pp.323-336
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• 2019

The Mesozoic activity on the Korean Peninsula is mainly represented by the Triassic post-collisional, Jurassic orogenic, and Cretaceous post-orogenic igneous activities. The diversity of mineralization by each geological period came from various geothermal systems derived from the geochemical characteristics of magma with different emplacement depth. The Cretaceous metallic mineralization has been carried out over a wide range of time periods from ca. 115 to 45 Ma (main stage; ca. 100 to 60 Ma) related to post-orogenic igneous activity, and spatial distribution patterns of most metal deposits are concentrated along small granitic stocks. The late Cretaceous metal deposits in the Gyeonggi and Yeongnam massifs are generally distributed along the boundary among the Gongju-Eumseong fault system and the Yeongdong-Gwangju fault system and the Gyeongsang Basin, most of them are in the form of a distal epithermal~mesothermal Au-Ag vein or a transitional mesothermal Zn-Pb-Cu vein. On the other hand, diverse metal commodities in the Taebaeg Basin, the Okcheon metamorphic belt and the Gyeongsang Basin are produced from various deposit types such as skarn, carbonate-replacement, vein, porphyry, breccia pipe, and Carlin type. In the late Cretaceous metallic mineralization, various mineral deposits and commodities were induced not only by the pathway of the hydrothermal solution, but also by the diversity of precipitation environment in the proximity difference of the granitic rocks. The diversity of these types of Cretaceous deposits is fundamentally dependent on the geochemical characteristics such as degree of differentiation and oxidation state of related igneous rocks, and ore-forming fluids generally exhibit the evolutionary characteristics of intermediate- to low-sulfur hydrothermal fluids.

• Ecology and Resilient Infrastructure
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• v.5 no.2
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• pp.82-87
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• 2018

Proliferation of algae on the surface of concrete or mortar in aquatic habitat has a negative impact on maintenance of concrete-based structures. Growth of algae may decrease stability of structure by bio-deterioration. In this study, we developed a functional mortar for restraining bio-deterioration by using $Cu^{2+}$ ion. The mortar contains soluble glass beads made of $Cu^{2+}$ ion, which can dissolve into water slowly. Mortars prepared with different ratio of glass beads (0, 2, 5, 10, and 15%) were placed in a culture medium with algae and incubated over a month period. Water chemistry, chlorophyll-a, and extracellular enzyme activities were measured. The incubation was conducted in both freshwater and seawater conditions, to assess applicability to both aquatic conditions. Overall, mortar with Cu glass exhibited lower chlorophyll-a content, suggesting that the functional mortar reduced algal growth. DOC concentration increased because debris of dead algae increased. Cu glass also decreased phosphatase activity, which is involved in the regeneration of inorganic P from organic moieties. Since, P is often a limiting nutrient for algal production, algal growth may be inhibited. Activities of ${\beta}$-glucosidase and N-acetylglucosaminidase were not significantly affected because carbon and nitrogen mineralization may not be influenced by the Cu glass beads. Our study suggests that functional mortar with Cu glass beads may reduce the growth of algae on the surface, while it has little environmental impact.

• Economic and Environmental Geology
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• v.21 no.3
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• pp.209-221
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• 1988

The ore deposit of the Ohtani mine is one of repesentatives of plutonic tungsten-tin veins related genetically to acidic magmatism of Late Cretaceous in the Inner zone of Southwest Japan. Based on macrostructures of vein filling on the order of ore body, three major mineralization stages, called stage I, stage II, and stage ill from earliest to latest, are distinguished by major tectonic breaks. The alteration zories are characterized by specific mineral associations in pseudomorphs after biotite. The alteration zones can be divided into two parts, i. e. a chlorite zone and a muscovite zone, each repesenting mineralogical and chemical changes produced by the hydrothermal alteration. The chloritic alteration took place at the beginning of mineralization, and muscovite alteration in additions to chloritic alteration took place at stage II and ill. The alteration zones are considered to be formed by either of two alteration mechanism. 1) The zones are formed by reaction of the rock with successive flows of solution of different composition and different stage. 2) The zones are formed contemporaneously as the solution move outward. Reaction between the solution and the wall-rock results in a continuous change in solution chemistry. The migration of the successive replacement of the fresh zone$\rightarrow$the chlorite zone$\rightarrow$the muscovite zone may have transgressed slowly veinward, leaving metasomatic borders between the different zones.

• Economic and Environmental Geology
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• v.37 no.3
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• pp.277-290
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• 2004

The trench exploration was carried out on the quartz veins of the Tanggung area of Java, Indonesia. The chemical values of quartz vein samples for hydrothermal alteration zones in this area are defined such as over values of Ag : 2∼190ppm(Celak); 2∼41 ppm(Cilangkap), Au : 21∼17,400 ppb(Celak); 24∼91,100 ppb(Cilangkap), Cu : 9∼3,340 ppm(Celak); 2∼l,600 ppm(Cilangkap), Pb : 60∼52,900 ppm(Celak); 16∼2,960 ppm(Cilangkap), Zn : 12∼13,950 ppm(Celak); 14∼1,520 ppm(Cilangkap), respectively. Two drilling areas, Mt. Subang area(Celak area) and Mt. Cilangkap area(Cilangkap area), have been chosen based on the factors such as, geologic settings associated with gold mineralizations, highly anomalous areas revealed by geochemical survey such as chemical analysis of ore and soil, trench exploration, statistical processing of the chemical analysis, and petrographic studies of igneous rocks related to its mineralization, and graphic presentation of anomalous areas.

• Economic and Environmental Geology
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• v.22 no.3
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• pp.253-266
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• 1989

The Cu-Pb-Zn-Ag hydrothermal vein type deposits which comprise the Dongil and Dong-cheogogsan mines occur within the Cretaceous sedimentary rocks in the Euiseong Basin of the southern Korean peninsula. The ore mineralization is contained within three stage(I,II and III) quartz and calcite veins. Ore minerals occur as dominant chalcopyrite, galena, sphalerite, tetrahedrite and Pb, Ag, Sb and Bi-bearing sulfosalts. Stage I ore minerals were deposited between $400^{\circ}C$ and $200^{\circ}C$ from the fluid with moderate salinities(7.0 to 4.5 eq. wt. % NaCl). Evidence of boiling suggests pressure of less than 150 bars during stage I mineralization. This pressure corresponds to maximum depths of 650 m and 1700 m, respectively, assuming lithostatic and hydrostatic loads. The data on mineralogy, temperature and salinity, together with information on the solubility of Cu complex, suggest that Cu deposition is a result of boiling coupled with declining temperature from $350^{\circ}$ to $250^{\circ}C$ or declining log $a_{o_2}$(from -29.8 to -35.9 atm.)and increasing in pH. Pb, Ag, Sb and Bi-bearing sulfosalts were deposited by cooling and dilution at temperature of less than $250^{\circ}C$ from the ore fluid with less than -35.9 atm. of log $a_{o_2}$.

• Economic and Environmental Geology
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• v.22 no.1
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• pp.21-34
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• 1989

Chindong granites are classified into granodiorite, tonalite and quartz-diorite, and Yucheon - Eonyang granites into monzo-granite by the Streckeisen diagram. These granitic rocks of Cretaceous age show trend of calc-alkaline magma, and the magmatic evolution from basic to acidic rocks is consistant with the general crystallization path of the Cretaceous granitic rocks in the Gyeongsang basin. On the basis of petrological and petrochemical data, variation of major elements (K, Na, Ca, Mg) and trace elements (Rb, Sr, Ba) including ore metals (Cu, Pb, Zn) in the Cretaceous granitic rocks were studied in detail in order to investigate geochemical difference of the granitic rocks in relation to mineralization between Cu province and Pb-Zn province in the Gyeongsang basin. There is clear difference in content of the major elements between Chindong granites and Yucheon-Eonyang granites : Chindong granites have low content of K (1.62%) and Na (2.53%), and high content of Ca (3.75%) and Mg (1.42%) whereas Yucheon-Eonyang granites have high content of K (3.56-3.60%), and low content of Ca (0.96-0.26%) and Mg (0.26-0.21%). There is also clear difference in content of trace lithophile elements between Chindong granites and Yucheon-Eonyang, granites : Chindong granites have low content of Rb (86ppm) and Ba (330ppm), and high content of Sr (405ppm) while Yucheon-Eonyang, granites have high content of Rb (144-161ppm) and Ba (983-1030ppm), and low content of Sr (157-136ppm). The lithophile trace elements of Rb and Sr vary with close relationship to major elements of K and Ca, respectively. Therefore, Chindong granites are much easily distinguished from Yucheon-Eonyang granites by using relationship of K with Rb and Ca with Sr : K<3%, Rb<100ppm, Ca<2% and Sr>200ppm for Chindong granites, and K>3%, Rb>100ppm, Ca<2%, and Sr<200ppm for Yucheon-Eonyang granites. There is not clear difference in content of trace ore metals between Chindong granites and Yucheon-Eonyang granites : Chindong granites of the Cu province have low Cu content (15ppm) which is nearly equal to 13-14ppm of Yucheon-Eonyang granites of the Pb-Zn province, and Yucheon-Eonyang granites have Pb content (29-27ppm) which is rather lower than 37ppm of Chindong granites. But Cu is anomalously high in the mineralized part of Chindong granites in Gunbuk-Haman area, and Zn is apparently higher in Yucheon-Eonyang granites (51-37ppm) than in Chindong granites (29ppm). K/Pb ratio is also c1early distinguishable between Chindong granites (<850) and Yucheon-Eonyang granites (>850). Thus, it may be possible to apply geochemical difference of the granites to distinguish whether a Cretaceous granitic body is Cu related rock or Pb-Zn related rock, and whether it belongs to Cu province or Pb-Zn province in the Gyeongsang basin.