• Economic and Environmental Geology
• /
• v.45 no.2
• /
• pp.157-167
• /
• 2012

This study aimed to interpret the provenance and firing temperature of pottery from Chipyeongdong site in Gwangju, Korea though mineralogical and geochemical methods and also investigated the post-depositional alteration of pottery in burial environments. It is also presumed that they were made of soils near the site because they have similar mineralogical composition and same geochemical evolution path. Based on the results of mineralogical analysis, the pottery samples are largely divided into 2 groups; $700^{\circ}C$ to $1,000^{\circ}C$ and 1,000 to $1,100^{\circ}C$. At some pottery fired at over $1,000^{\circ}C$, it is thought that the refinement of raw materials were processed to remove macrocrystalline fragments. However, it was found that phosphate in soil environments formed amorphous aggregates with Al and Fe within the pores and voids on pottery fired at the low temperature. It indicates the contamination of pottery after burial.

• The Journal of the Petrological Society of Korea
• /
• v.9 no.2
• /
• pp.70-83
• /
• 2000

The purpose of this study is to identify the petrographic and geochemical characteristics of four granitic masses and clanfy for the origin and relationship among the masses. These granitic rocks are distributed in the eastern part of Yangsan fault in the Kyongsang basin, southeastern part of Korea. Based on the mineralogy and texture, the granitic rocks are divided into three facies; granodiorite, porphyritic fine-grained granite, and equigranular granite. According to the result of modal analysis, northern part and most of the southern part of Daebon granitic rocks are plotted in granodiorite field and the rest part of the xocks are plotted in granite field. These granitic rocks belong to the sub-alkaline series, and are subdivided into calc-alkaline series. The rare earth elements normalized bv chondrite show LREE is more enriched than HREE and the lowest values in O-w m- i t e and Daebon equigranular granite. The crystallization pressures and temperatures of minimum melt compositions of granitic rocks estimated from the study area are about 0.5-1 kbar and $700~820^{\circ}C$, respectively. Referring to the petrographic characteristics, geochemical data and radiogenic age data, Oyu granite was emplaced in the Paleocene, but Daebon granodiorite, Sanseo porphyritic granite, and Hoam equigranular granite are co-magmatic differentiation products, were emplaced in the Eocene.

• Journal of Conservation Science
• /
• v.26 no.1
• /
• pp.1-12
• /
• 2010

The crucibles of Baekje Kingdom from the Ssangbukri Site which were used for glass and metal melting had light brown, grayish blue and grayish brown colored bodies. In thin section, the crucibles contained numerous quartz grains and pottery fragments. The surface was covered with fine grained quartz for thermal resistance. Based on decomposition of mica group minerals and formation of mullite detected by X-ray diffraction analysis, it was inferred that all crucibles have been fired over $1,000^{\circ}C$. It was also found that firing temperature has exceeded $1,100^{\circ}C$ in some crucibles because feldspar was not detected. The maximum temperature was assumed at $1,200^{\circ}C$. The magnetic susceptibility values and geochemical characteristics sorted out the crucibles into two groups that differed from the characteristics of the local soils. This reflected geological setting of the site where the alluvium was formed from two kinds of surrounding rock masses, granite gneiss and biotite granite. However, the local soils had similarities with the crucibles in weathering degree and geochemical behavior of major elements. In consequence, it was considered that the raw clay of the crucibles was supplied from the local area of the site.

• Journal of Conservation Science
• /
• v.30 no.2
• /
• pp.205-217
• /
• 2014

The stone artifacts in Bronze age from the Sinsongri sites in Seosan, Korea were studied on material characteristics and provenance presumptions. The use and rock names of the artifacts are a stone before processing, two semifinished stone arrowheads and a grinding stone plate by slates. In addition, there is semifinished stone arrowhead by andesitic rocks. The slate could be observed easily around the site, and the andesitic rock could be confirmed typical occurrences of the all kinds of rocks around the Kanwoldo and Hwangdori, Anmyun area above 10km from the site. As a result of analysis which is comparing between stone artifacts and same kinds of raw material rocks, the stone artifacts made by slates have similar lithology and geochemical characteristics however, the stone artifacts made by andesitic rocks are found a some different part of characteristics to the same kind of raw material rocks. Comparing of major, rare earth, compatible and incompatible elements about stones artifacts made by slates and by the same kinds of raw material rocks have same geochemical patterns. However stone artifacts made by andesites and the raw material rocks are confirmed some differences of geochemistry. Therefore the slate stone artifacts in Sinsongri site suggest that these are domestic-type which are made of the rocks around the site, and it was understood that the andesitic stone artifacts are foreign-type which need to get more geological survey and study about different volcanic artifacts of the site around the area.

• Economic and Environmental Geology
• /
• v.34 no.1
• /
• pp.71-88
• /
• 2001

The Geochemica] and isotope studies on the $CO_2$-rich water from the Shinchon area were carried out. The Shinchon $CO_2$-rich water belongs to Ca(Na)-$HCO_3$ type showing very high $P_{CO_{2}}$ ( $10^{-0.35}$ ~ $10^{0.29}$ atm) and TDS (835-3,144 mg/L). The results of geochemical and isotope analysis indicate that $CO_2$ gas is originated from the deep seated source such as mantle or magmatic gases. The $CO_2$-rich water was evolved by interaction with deep-seated granite and major water-rock interaction was dissolution of p]agioclase resulting high Na content of $CO_2$-rich water. Precipitation and dissolution of secondary calcite might be accompanied with the dissolution of plagioclase maintaining Na/Ca ratio. High contents of K and $SO_4$ indicate that the geochemical characteristics of $CO_2$-rich water were partially affected by interaction with upper sedimentary rock during uprising to surface. N03 and tritium contents suggest that the $CO_2$-rich water was mixed with low $CO_2$ groundwater at some locations. The oxygen-hydrogen isotopes show that all water samples were derived from meteoric waters and the $CO_2$-rich water was isotopically re-equilibrated with lighter $CO_2$ gas. Although some carbon isotope data show isotopically heavy values, carbon isotope data indicate that the $CO_2$ gas was possib]y derived by deep source.

• Journal of the Mineralogical Society of Korea
• /
• v.21 no.1
• /
• pp.67-83
• /
• 2008

The sericite ore deposits formed in the Precambrian granitic rock at the Bonghwa area, Kyungsangbuk-do, South Korea. The geochemical and mineralogical characteristics of sericite occurred in Daehyun and Seonghwang mine were analyzed using petrographic microscope, XRD, EPMA, XRF and ICP. An alteration mechanism was also studied. Sericitization occurred within the granitic rock by hydrothermal alteration. From the careful study on the occurrence and mineral assemblage, four alteration zone were clearly identified. These zones reflect progressive hydrothermal alteration process. All sericites belong to $2M_1$ polytype and their mineralogical and geochemical properties are close to illite. The sericite ores show various colors, but the characteristics of major element compositions and crystal structures are not different. The trace element analysis, however, indicates that the difference in color attribute to the abundance of Cr and Ti: bluish green colored sericite are enriched in Cr and blackish green colored sericite enriched in Ti. The formation of sericite ore deposit in the granitic rocks are closely relate to fracture system such as fault and joint. It is considered that the sericite ore deposits in this area were formed by very simple hydrothermal alteration occurred along the fracture zones in granitic rocks with absence of other hydrothermally altered minerals such as kaolin and pyrophyllite.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.4 no.4
• /
• pp.321-328
• /
• 2006

A basic research was conducted on the mineral weathering and geochemical characteristics in the KURT (KAERI Underground Research Tunnel), which was recently constructed at a site in KAERI. Some rock samples exposed during the KURT construction were examined using a microscope and chemical analysis for some micro-changes of the rocks caused by the chemical weathering. The weathered granite has some small and fine cracks around the rock-forming minerals. In particular, there are a characteristic weathering of feldspar mineral and a preferential leaching of Ca component from the mineral dissolution. In addition, by the dissolution of biotite containing $Fe^{2+}$ component there were iron-oxides precipitates as secondary products into the microcracks of around minerals. The results also show that the micro-cracks initiated from the mineral interior are extended and connected into the larger cracks along the grain boundary with the progress of the weathering. Thus, it is considered that some chemicals dissolved from the fresh rock would be involved in the formation of secondary minerals and migrate interacting with them.

• Economic and Environmental Geology
• /
• v.42 no.2
• /
• pp.107-120
• /
• 2009

Spacial variation in organic components and temporal variation in the origin was examined through the organic geochemical (TC, TN, TS, $CaCO_3$, TOC, C/N, and $\delta^{13}C$) and pyrolysis analysis (HI, OI, and Tmax) in the core sediments which were acquired in the continental shelf of the South Sea close to Seomjin River. Levels of TC, TN, and TS show relatively low and constant in the core SJ03 located close to the Seomjin River mouth, while those are increased a little with being varied with low amplitude in the core SJ02 and SJ04 acquired at the middle of inner shelf area. They fluctuated with high amplitude in the core SJ01 and SJ05 near to the outer boundary of inner shelf. The vertical characteristics of organic components in the core SJ01 acquired at the outer boundary show that the area has undergone distinctly the environmental change at 9.0 kyr B.P. After 9.0 kyr B.P., Levels of TC, TOC, TN, $CaCO_3$, $\delta^{13}C$, HI, and Tmax are rapidly increased, while C/N and or are significantly decreased. Even though the contents of organic components are not high, such a changes reflect that the terrigenous organic matters were predominant before 9.0 kyr B.P due to the influence of Seomjin River, but after then, the marine organic matters have dominated due to the inflow of the Tshusima current.

• Economic and Environmental Geology
• /
• v.41 no.2
• /
• pp.183-199
• /
• 2008

This study is focused on characterization of the physio-chemical and mineralogical properties, investigation of their vertical changes in the tailing profile of the Guryoung mining area, classification of the profile into distinct zones, and condition conceptual model of physio-chemical conditions and phases-water relationships controlling the element behaviors in the tailings. The upper part of the groundwater is characterized by the high contents of $Fe_2O_3$ and $SO_3$ for whole rock analysis, low pH, and the occurrence of jarosite, schwertmannite and Fe-oxyhydroxide as the secondary mineral phases. The tailing profile can be divided into the covering soil, jarosite zone, Fe-sulfate zone, Fe-oxyhydroxide and gypsum-bearing pyrite zone, calcite-bearing pyrite zone, soil zone, and weathered zone on the based of the geochemical and mineralogical characteristics. The profile can be sampled into the oxidized zone and the carbonate-rich primary zone with the dramatic changes in pH and the secondary mineral phases. The conceptual model proposed for the tailing profile can be summarized that the oxidation of pyrite is the most important reaction controlling the changes in pH, the dissolution of the primary silicates and carbonates, the precipitation of secondary mineral phases, acid-neutralizing, and heavy metal behaviors through the profile.

• Spatial Information Research
• /
• v.14 no.1 s.36
• /
• pp.129-150
• /
• 2006

Mineral potential mapping is an important procedure in mineral resource assessment. The purpose of this study is to analyze mineral potential using weight of evidence model and a Geographic Information System (GIS) environment to identify areas that have not been subjected to the same degree of exploration. For this, a variety of spatial geological data were compiled, evaluated and integrated to produce a map of potential mineral in the Gangreung area, Korea. for this, a spatial database considering mineral deposit, topographic, geologic, geophysical and geochemical data was constructed for the study area using a GIS. The used mineral deposits were non-metallic(Kaolin, Porcelainstone, Silicastone, Mica, Nephrite, Limestone and Pyrophyllite) deposits of sedimentary type. The factors relating to mineral deposits were the geological data such as lithology and fault structure, geochemical data, including the abundance of Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Si, Sr, V, Zn, $Cl^-,\;F^-,\;{PO_4}^{3-},\;{NO_2}^-,\;{NO_3}^-,\;SO_{42-}$, Eh, PH and conductivity and geophysical data, including the Bouguer and magnetic anomalies. These factors were used with weight of evidence model to analyze mineral potential. Probability models using the weight of evidence were applied to extract the relationship between mineral deposits and related factors, and the ratio were calculated. Then the potential indices were calculated by summation of the likelihood ratio and mineral potential maps were constructed from Geographic Information System (GIS). The mineral potential maps were then verified by comparison with the known mineral deposit areas. The result showed the 85.66% in prediction accuracy.