• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.393-401
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• 2018

The aim of this study was to analyze the characteristics of ground subsidence and land-creeping in four mining areas in Korea. Land creeping were occurred by large-scale sinkholes and tensile cracks in the mining areas. This ares showed the shape as large-scale landslides by the collapsed stone debris pushed in the direction of gravity. The rock type in the No. 4 survey area was sandstone and shale, whereas that of other three areas was limestone. The limestone was generally vulnerable to land creeping. The ground subsidence and land creeping in four mining areas were located near the ridge of the mountain. The land creeping by ground subsidence in the mining areas showed complex shapes due to the cavity of underground tunnel and the colluvial debris by gravity in the mountain area, whereas the land creeping in Korea are in the shape of landslide. The average slope of the mining area was ranged from $30.4^{\circ}$ to $33.7^{\circ}$. The values were higher ($1.5^{\circ}{\sim}4.8^{\circ}$) than the average slopes for landslide areas.

• Economic and Environmental Geology
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• v.23 no.4
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• pp.369-381
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• 1990

Most of significant ore deposits in South Korea such as the Sangdong W - Mo, the Yeonhwa Pb-Zn and the Geodo Cu-Fe skarn ore deposits occur at the southern limb of the Hambaeg syncline in the Taebaeg Basin. The mineralization took place in the interbedded limestone of the Myobong Formation and the Pungchon limestone of the Great Limestone Group of the Cambrian age, generally striking E-W and dipping 25-30 degrees north. There are no outcrops of the skarn-type orebody at the northern limb of the syncline. In order to find a clue of a possible hidden orebody localized at the limestones in the northern limb, a lithogeochemical exploration by using carbon isotope and some elements such as Si, Ca, Fe and Al at the Sangdong Mine area has been attempted as for a modelling study. For this study, 45 samples from the Pungchon limestone which do not show any megascopic indication of mineralization have been taken in both the mineralized zone and the unminerallized zone at the Sangdong Mine area. Analytical data show that there are big differences in the contents of CaO and $Al_2O_3$ between the Pungchon limestone of the mineralized zone and that of the unmineralized zone. Carbon isotope data exhibit that ${\delta}^{13}C$ values of the Pungchon limestone in the mineralized zone are highter than those in the unmineralized zone. The difference in the analytical values of CaO, $Al_2O_3$ and the carbon isotope between the mineralized and the unmineralized zones is as follows ; Unminerallized zone Mineralized zone CaO 51.3% 43.5% $Al_2O_3$ 0.6% 2.4% ${\delta}^{13}C$ -0.39 permil -0.56 permil $Fe_2O_3$ 0.9% 1.4% $SiO_2$ 3.0% 2.4% The decrease in the Si content of the Pungchon limestone in the mineralized zone is contrary to the result of the previous study (Moon, 1987). On the basis of identification of the increase in the Al content of the limestone in the mineralized zone, it could be deduced that the decrease in the Si content of the Pungchon limestone might be due to the result of increase in the alteration products mainly occurred along fracture-system such as joint cracks or minor faults and that the phenomena shown by the Si and Al content in the mineralized zone might be derived from the thermal effect of granite extended mineralizing activity to the overlied limestone on the surface. Higher mean values of Fe and Al as well as lower mean values of carbon content and the ${\delta}^{13}C$ than mean values of those in the Pungchon limestone at the northern limb of the Hambaeg Syncline may be applicable in exploration for blind orebodies.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.164-179
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• 1991

Korean agriculture has encountered two problems. One is internal income disparity between rural and urbarn area and the other is external Uruguay Round trade problems as an abolition of direct and indirect import barriers, reduction in export subsidies and to reduce internal price supports. These problems will be brought severe farm problems such as decreasing farm household income and repressing agricultural growth in the near future. Considering the above inevitable facts Korean government has implemented several development projects such as rural industrial area development project, rural special production area development project, leisuresight seeing farm development project, traditional food development project, unskilled labor training project for off-farm employment and so on, to increase farm household income through off-farm income increase. This study was mainly concentrated on the identification of operational problems and post evaluation of the rural special production area development projects which aimed at increasing non-farm incomes and giving employment opportunity for rural farmers in small factories processing regional special farm products and mine products. The main findings and problems to be solved for the successful project implementation are as followed ; 1. Total number of the special production area development projects as of the end of 1991 was amount to 138, and total number of farm household participated were estimated at 2,079, and total amount of off-farm income per farm household was reached to 3,011 thousand won. 2. The total number of processed special products have increased from 21 items in 1981 to 56 items in 1991. On the other hand the total number of farm household participated in the projects have decreased from 2,518 to 2,079 during same period. 3. Total amount of investment for the projects has increased from 1,429 million won in 1981 to 24,760 million won in 1991 but the rate of G'T loan of the total investment has reduced from 24.5% to 5.2% during same period. 4. 138 special production area development project are classified into 6 kinds of commodity groups such as 19 of general industrial good production areas, 52 of folks-industrial art objects production areas, 39 of food processing areas, 9 of fiber and texstile processing areas, 18 of agricultural and fishery inputs processing areas and 1 of stone processing area. 5. The total production value in 1990 was estimated 20,169 million won of which export was amount to 2,627 million won. 6. The finacial rate of return of the UNGOK KUGIJA Tea processing Project operated by UNGOK coops and BAKSAN ginseng tea processing project were estimated at 45.4% (B/C Ratio=1.17, NPV=152.5 million won) and 17.7% (B/C Ratio=1.12, NPV=120.2 million won) respectively. 7. More favorite terms and condition of the loan including collateral problems have to be given to farmers participated. Heavy investment and G'T subsidy policies should be started for the successful project implementation anf farm household income increase. 8. To expand market demand of the rural special goods G'T have to provide special program of TV or other mass media for commodity propaganda and the total cost concerned must be supported by G'T subsidy. 9. The special farm products as GUGUJA,MOSI'Ramie', Ginseng. SOGOKJU,HEMP,Mushroom.DUGYUNJU and Chesnut processing projects have to be propelled and expanded for off-farm income increase in Chung Nam Province. 10. Direct operational pattern of the special production area by coops is more favorable to farmers and recommendable considering with off-farm income increase and market demand creation throughout Korea. 11. In rural area, special organizations for project appraisal are not exist. Accordingly special training program, project appraisal, formulation and preparation for civil servants concerned have to be prepared for project selection and sound implementation under limited budget and financial support.

• Economic and Environmental Geology
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• v.15 no.3
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• pp.123-154
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• 1982

Petrochemical, K-Ar dating, Sand Rb/Sr isotopes, metallogenic zoning, paleomagnetic and geotectonic studies of the Gyongsang basin were carried out to examine applicability of plate tectonics to the post-late Cretaceous igneous activity and metallogeny in the southeastern part of Korean Peninsula. The results obtained are as follows: 1. Bulgugsa granitic rocks range from granite to adamellite, whose Q-Ab-Or triangular diagram indicates that the depth and pressure at which the magma consolidated increase from coast to inland varying from 6 km, 0.5-3.3 kb in the coastal area to 17 km, 0.5-10 kb in the inland area. 2. The volcanic rocks in Gyongsang basin range from andesitic to basaltic rocks, and the basaltic rocks are generally tholeiitic in the coastal area and alkali basalt in the inland area. 3. The volcanic rocks of the area have the initial ratio of Sr^{87}/Sr^{86} varying from 0.706 to 0.707 which suggests a continental origin; the ratio of Rb/Sr changing from 0.079-0.157 in the coastal area to 0.021-0.034 in the inland area suggests that the volcanism is getting younger toward coastal side, which may indicate a retreat in stage of differentiation if they were derived from a same magma. The K_2O/SiO_2 (60%) increases from about 1.0 in the coastal area to about 3.0 in the inland area, which may suggest an increase indepth of the Benioff zone, if existed, toward inland side. 4. The K-Ar ages of volcanic rocks were measured to be 79.4 m.y. near Daegu, and 61.7 m.y. near Busan indicating a southeastward decrease in age. The ages of plutonic rocks also decrease toward the same direction with 73 m.y. near Daegu, and 58 m.y. near Busan, so that the volcanism predated the plutonism by 6 m.y. in the continental interior and 4 m.y. along the coast. Such igneous activities provide a positive evidence for an applicability of plate tectonics to this area. 5. Sulfur isotope analyses of sulfide minerals from 8 mines revealed that these deposits were genetically connected with the spacially associated ingeous rocks showing relatively narrow range of ${\delta}^{34}S$ values (-0.9‰ to +7.5‰ except for +13.3 from Mulgum Mine). A sequence of metallogenic zones from the coast to the inland is delineated to be in the order of Fe-Cu zone, Cu-Pb-Zn zone, and W-Mo zone. A few porphyry type copper deposits are found in the Fe-Cu zone. These two facts enable the sequence to be comparable with that of Andean type in South America. 6. The VGP's of Cretaceous and post Cretaceous rocks from Korea are located near the ones($71^{\circ}N$, $180^{\circ}E$ and $90^{\circ}N$, $110^{\circ}E$) obtained from continents of northern hemisphere. This suggests that the Korean peninsula has been stable tectonically since Cretaceous, belonging to the Eurasian continent. 7. Different polar wandering path between Korean peninsula and Japanese islands delineates that there has been some relative movement between them. 8. The variational feature of declination of NRM toward northwestern inland side from southeastern extremity of Korean peninsula suggests that the age of rocks becomes older toward inland side. 9. The geological structure(mainly faults) and trends of lineaments interpreted from the Landsat imagery reveal that NNE-, NWW- and NEE-trends are predominant in the decreasing order of intensity. 10. The NNE-trending structures were originated by tensional and/or compressional forces, the directions of which were parallel and perpendicular respectively to the subduction boundary of the Kula plate during about 90 m.y. B.P. The NWW-trending structures were originated as shear fractures by the same compressional forces. The NEE-trending structures are considered to be priginated as tension fractures parallel to the subduction boundary of the Kula plate during about 70 m.y. B.P. when Japanese islands had drifted toward southeast leaving the Sea of Japan behind. It was clearly demonstrated by many authors that the drifting of Japanese islands was accompanied with a rotational movement of a clock-wise direction, so that it is inferred that subduction boundary had changed from NNE- to NEE-direction. A number of facts and features mentioned above provide a suite of positive evidences enabling application of plate tectonics to the late Cretaceous-early Tertiary igneous activity and metallogeny in the area. Synthesizing these facts, an arc-trench system of continental margin-type is adopted by reconstructing paleogeographic models for the evolution of Korean peninsula and Japan islands. The models involve an extention mechanism behind the are(proto-Japan), by which proto-Japan as of northeastern continuation of Gyongsang zone has been drifted rotationally toward southeast. The zone of igneous activity has also been migrated from the inland in late-Cretaceous to the peninsula margin and southwestern Japan in Tertiary.

• Economic and Environmental Geology
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• v.19 no.spc
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• pp.53-71
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• 1986

Detailed studies of regional geology and geochemistry of the tungsten mineralisation of Ogbang mine were carried out; in particular geochemical trends of major and trace elements of different lithological units, in comparison with those of the Sangdong area, together with igneous plutons in the area. The Ogbang deposit is in a pegmatitic association localised only in amphibolites whilst pegmatites in adjacent schists and gneisses are barren. The tungsten is geochemically accompanied by increase of $K_2O$, $Na_2O$ and Rb, and depletion of Sr. The trend of Rb/Sr ratio to the type of mineralisation, in commonly seen in the mineralised granites of the world, suggests that the tungsten in the Ogbang pegmatites was supplied by hydrothermal processes which at the same time caused Rb enrichment and Sr depletion. These trend could be of use in the search for new ore bodies in common with those of mineralised granitic or pegmatitic host rocks. There is no evidence that the granites in the area have any genetic influence spacially and temporarily on the initial scheelite formation.

• Economic and Environmental Geology
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• v.26 no.3
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• pp.337-347
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• 1993

Mineralogical and geochemical studies on some pyrophyllite deposits in Milyang area, Kyeongnam Province (Milyang and Sungjin mine) were carried out in order to investigate dispersion patterns of chemical elements in altered volcanic wallrocks, and to interpret genetic environments of the pyrophyllite deposits. Cretaceous andesitic and tuffaceous rocks, and pyrophyllite ore specimens were collected from the dumps and drilling cores. Andesitic wallrocks were grouped as unaltered and altered rocks in the order of pyrophyllitization. Vertical dispersion patterns and relative mobilities of chemical elements in volcanic wallrocks were discussed. Geochemical environment in the Milyang area is characterized by the occurrence of boron minerals such as dumortierite coexisting with pyrophyllite ores, and tourmaline in granitic rocks. Unaltered andesitic rocks are mainly composed of plagioclase, pyroxene and hornblende, and were propylitized and saussuritized. Altered andesitic rocks are bleached and consist of quartz, sericite, pyrophyllite, kaolinite, chlorite and disseminated pyrite. Pyrophyllite ores are mainly composed of quartz, pyrophyllite, dumortierite, dissemianted pyrite and some diaspore. Enrichment of $SiO_2$, $Al_2O_3$, LOI (loss on ignition), As and Cr, and depletion of $K_2O$, $Na_2O$, CaO, MgO and total Fe are characteristic during alteration process. The REE patterns show that the pyrophyllite deposits could be originated from the continental margin volcanics. The $(La/Lu)_{cn}$ ratios of the pyrophyllite ores increase from 4.2~23.2 to 2.67~128.8 owing to strong acidic hydrothermal alteration. Vertical dispersion patterns of $Al_2O_3$, $K_2O$, $Na_2O$, CaO, MgO, $Fe_2O_3$ (total Fe), As, Au, Sb, Cr and Sr in the wallrocks show the location of orebodies. Particularly dispersion patterns of $Al_2O_3$ and Cr indicate the extension of orebodies. Anomalous distribution of Au, As and Sb in wallrocks shows potential for gold occurrence below the pyrophyllite deposits. Judging from the relative mobilities of elements in wallrocks, $Al_2O_3$ could be added from hydrothermal solution, and the silicified rone be formed from the excess of $SiO_2$.

• Economic and Environmental Geology
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• v.47 no.3
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• pp.227-235
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• 2014

For technology level assessment of KIGAM World Class Laboratories (WCL) candidates, bibliometric and qualitative analysis was conducted on their research papers listed on the SCIE database during 2009-2012. For the six research areas of geoscience and mineral resources, a research excellence indicator was applied using a Modified Rank Normalized Impact Factor (mrnIF), which was introduced by Heo et al. (2008) and Cho (2013). The KIGAM research department in rare metals utilization had the highest score for Impact Factor (IF) per paper in 2012 but the groundwater department or the exploration geophysics department came first based on the position and the mrnIF. Applying the mrnIF, the KIGAM research department in groundwater achieved excellent results in 2009 and 2011 and the urban mine department or exploration geophysics department came first place in other years. In the groundwater area, the percentage of research papers over 80 or 90 mrnIF, using Cho (2013)'s research excellence index, was the highest in 2011. The Cho (2013)'s excellent research indicator, 20%, the ratio of over 90 mrnIF was matched in the urban mining area for the whole research period, 2009-2012, and in the groundwater area for several years except 2010. Qualitative analysis of research papers can show the technology level of research departments. KIGAM World Class Laboratories (WCL) candidates should focus on increasing the quality and the quantity of their research papers.

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.67-83
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• 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 the Mineralogical Society of Korea
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• v.22 no.2
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• pp.163-176
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• 2009

The pyrophyllite deposits located in Jinhae area have been studied through field observations and laboratory works including the X-ray diffraction (XRD), X-ray fluorescence (XRF), Electron probe microanalyzer (EPMA) and Inductively Coupled Plasma (ICP). The pyrophyllite deposits consist of mainly illite, dickite, pyrophyllite, diaspore, chlorite, pyrite and copiapite. According to the mineral assemblages, geological occurrences and alteration modes, the altered rocks can be classified into four types: Type A; quartz with silicifictaion, Type B; quartz + illite with illitization, Type C; quartz + dickite + illite with kaolin alteration, Type D; pyrophyllite + illite + dickite + diaspore with pyrophyllite alteraion. Rocks in Type A, which is generated by silicifictaion, have high $SiO_2$ contents more than 90 wt% and distinctive equigranular textures with microcrtstalline quartz. The pyrophyllites from the study area belong to 2M polytype. The host rocks of the pyrophyllite ore in this mine are rhyolitic rock, andecitic tuff and volcanic breccia. The alteration products seem to be controlled by the different lithology of the host rocks. The hydrothermal solution formed the deposits would be inferred to the acidic and have relatively high ionic activity of hydrogen and silica judging from alteration mineral assemblage. Pyrophyllite alteraion zone is generated by highest temperature condition of all alteration zone.

• Journal of Mushroom
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• v.3 no.4
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• pp.145-153
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• 2005

Two hundred seventy-four microorganisms were isolated from the soil of abandoned mines around for selecting the heavy metal-degrading strains and their microbial diversity was analyzed. The specimens of macrofungi were isolated from the soil of abandoned mines around for selecting the heavy metal-degrading strains. Eunseong and Dogok in Gyeongsangbuk-do, for selecting the heavy metal-degrading strains. Soil was also collected from same location. Contents of heavy metals (Cd, Cu, Pb, Zn, Ni, Cr, and As) were determined spectrometically in fruiting bodies of forty eight wild macrofungi specimens with soils. When the analysed their transfer factor from soil to fruiting body, Amanita volvata have the highest transfer factor of cadmium and arsenic. And Mycena pura showed the highest in mercury, Marasmius pulcherripes in zinc, Laccaria laccata in nickel, and Collybia confluens in chrome. When compare the population of mushrooms between the contaminated mines and Mt. Chiak as the healthy area, Genus Russula and Collybia were collected both area, but Leucocoprinus, Coprinus, Suillus, Lepiost, Gyroporus, Lepista, Microstoma, Stropharia, and Agrocybe were only in the contaminated mine area.