• Advances in environmental research
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• v.5 no.2
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• pp.95-108
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• 2016

Urban geology is the study of urban geologic environments to provide a scientific basis for rational land use planning and urban development and provides information on geologic environments as a basis for city planners. Based on AEG recommendations, urban geological studies covered the urbanism and historical backgrounds, geological setting, engineering geological constraints and environmental assessments of understudied cities. The aim of this study is to provide a good view of urban geology of Tabriz city the capital of East Azerbaijan province in Iran. The topics of discussions about Tabriz city urban geology are included geologic (geomorphology, geology, climatology and hydrogeology), engineering geological (earthquake, landslide and geotechnical hazards investigations) and environmental characteristics (air, soil and water hazards assessment).The results of the urban geologic studies indicated that Tabriz city in terms of engineering geological and environmental constraints is at high risk potential and in terms of seismic activity and landslide instability is highly potential. In terms of air, soil and water pollution there are many important environmental concern in this city.

• Journal of The Geomorphological Association of Korea
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• v.28 no.1
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• pp.1-12
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• 2021

This study tried to reveal relative surface denudation resistance and ranking by geologic types in the Southern Korean Peninsula using an 1:250,000 digital geologic map and ASTER GDEM. Among rock types such as igneous, sedimentary and metamorphic rocks, metamorphic rock showed the greatest resistance to surface denudation. The most resistant rock to surface denudation by geologic periods (e.g., the Precambrian, Paleozoic, Mesozoic and Cenozoic) was found from the Precambrian. Among the major tectonic settings in the Southern Korean Peninsula such as the Gyeonggi massif, Okcheon belt, Yeongnam massif, Gyeongsang basin and Pohang basin, the Okcheon belt indicated the greatest resistance. The most and least resistant rocks from the representative nine rocks in the Southern Korean Peninsula were Paleozoic limestone, and Cretaceous sedimentary rock and Cenozoic sedimentary rock, respectively. This study suggests that Paleozoic limestone, Cretaceous volcanic rock, Paleozoic sedimentary rock and Precambrian gneiss can be regarded as hard rocks with high elevation, steep slope and complicated relief, while soft rocks with low elevation, gentle slope and simple relief are Jurassic granite, Cretaceous sedimentary rock and Cenozoic sedimentary rock.

• Journal of the Mineralogical Society of Korea
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• v.25 no.4
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• pp.211-220
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• 2012

The numerical modeling and simulation have been used increasingly as tools for examining and interpreting the bulk structure and properties of materials. The use of molecular dynamics (MD) simulations to model the structure of materials is now both widespread and reasonably well understood. In this research, we introduced the numerical method to calculate the physico-chemical properties such as a diffusion coefficient and a viscosity of clay mineral. In this research, a series of MD calculations were performed for clay mineral and clay-water systems, appropriate to a saturated deep geological setting. Then, by using homogenization analysis (HA), the diffusion coefficients are calculated for conditions of the spatial distribution of the water viscosity associated with some configuration of clay minerals. This result of numerical analysis is quite similar to the previous experimental results. It means that the introduced numerical method is very useful to calculate the physico-chemical properties of clay minerals under various environmental conditions.

• The Journal of Engineering Geology
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• v.22 no.2
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• pp.157-171
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• 2012

The slope design of an open-pit mine must ensure slope stability and economic feasibility. The overall slope angle of the pit is therefore the main factor of concern because of limited support or reinforcement options available in such a setting. This study examines the optimal measurement system for monitoring the behavior of the slope in an open-pit mine using displacement measurement, data analysis, and numerical simulations for a coal mine at Pasir, Indonesia. The area of slope to be managed is extensive and the maximum displacement, as calculated by numerical analysis, is about 3,000 mm. The displacement data, measured by inclinometer and GPS, were analyzed, and the applicability of SSR (slope stability radar) was reviewed in comparison with other monitoring systems.

• Journal of Soil and Groundwater Environment
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• v.17 no.2
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• pp.22-27
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• 2012

$^{226}Ra$ in groundwater could be analyzed by various methods. LSC (liquid scintillation counter) is used to measure its activity of Ba co-precipitates with Hisafe III scintillation cocktail solution. Counting efficiency was obtained using NIST $^{226}Ra$ standard solution in triplicate and calculated $^{226}Ra$ concentration using the efficiency values. $^{226}Ra$ values of 19 groundwaters having Gross-${\alpha}$ concentrations of more than 5 pCi/L ranged from ND (${\leq}$ 0.1 pCi/L) to 1.18 pCi/L. Geologic settings of the 19 areas are composed of granitic rocks of Pre-Cambrian and Jurassic and Cretaceous, gneiss (schist) of Pre-Cambrian, and volcanic rocks of Cretaceous. No relationship was shown among $^{226}Ra$ a concentrations and in-situ water quality data, and Gross-${\alpha}$, uranium, radon concentrations.

• Economic and Environmental Geology
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• v.33 no.1
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• pp.1-18
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• 2000

Lens shaped and stratiform titanomagnetite orebodies in the Boreumdo iron mine are closely associated with amphibolite which intruded into Precambrian metasediments. Mineralogical and petrochemical analyses of amphilbolite and titanomagnetite ores were carried out in order to interpret the origin of amphilbolite and the genesis of titanomagnetite ore deposits. Amphibolites belong to orthoamphilbolite interms of Niggli value and mineralogy, and are characterized by the occurrence of relict olivine. The amphilbolites responsible for titanomagnetite mineralization have extremely high content of $TiO_2$, ranging from 2.12 to 4.59 wt.% with the average value of 3.43 wt.%. Amphibole minerals in amphibolites are consist mainly of calcic amphiboles such as hornblende, ferroan pargasitic hornblende and tremolite. Most plagioclases belong to andesine ($An_{30-50}$\ulcorner). The metamorphic temperature and geobarometric pressure which are calculated by the calcic amphibole-plagioclase geothermometer and calcic amphilbole geobarometer are estimated to be 537$^{\circ}C$~579$^{\circ}C$(avg. 555$^{\circ}C$) and 2.9~6.6 kbar (avg. 4.5 kbars), respectively. It shows a typical amphibolite facies. Based on the mineral chemistry and petrochemisty of amphibolites and iron ores which are composed mainly of titanomagnetite and ilmenite in the Boreumdo iron mine, the titaniferous oxide melts could be immiscibly separatd from the titaniferous ultrabasic magma. The genesis of the Boreumdo titanomagnetite ore deposits are analogous to the Soyeonpyeongdo and Yonchon iron ore deposits in terms of their mineralogy, mineral chemistry and geologic setting.

• Journal of Environmental Science International
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• v.16 no.5
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• pp.561-569
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• 2007

This study used SCS-CN method to estimate the real recharge of the study area which is one of the most reasonable techniques to estimate groundwater recharge when there is no available runoff data in a watershed. From the results of tile real recharge analysis for the study area using SCS-CN method, it was analyzed that the year 1994 when the drought was severe shotted the lowest recharge of 106.3mm with recharge rate of 12.4%, and the highest recharge of 285.6mm with recharge rate of 21.8% occurred in 1990. Yearly average recharge of 213.2mm was obtained, and tile average recharge rate was 16.9%/year. KOG-FLOW model which has powerful post process functions consists of setting environments for input parameters in Korean language, and help function is added to each input data. Detailed information for each parameter is displayed when the icon is placed on the input parameters, and geologic boundaries or initial head data for each layer can be set easily on work sheet. The relative errors (R. E.) for each model's observed values and calculated values are $0.156{\sim}0.432$ in case of KOG-FLOW, and $0.451{\sim}1.175$ in case of WINFLOW, therefore it is known that KOG-FLOW model developed in this study produced results compared to observed head values.

• The Journal of Engineering Geology
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• v.20 no.3
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• pp.243-255
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• 2010

The slope design of an open-pit mine must consider economical efficiency and stability. Thus, the overall slope angle is the principal factor because of limited support or reinforcement options available in such a setting. In this study, slope displacement, as monitored by a GPS system, was analyzed for a coal mine at Pasir, Indonesia. Predictions of failure time by inverse velocity analysis showed good agreement with field observations. Therefore, the failure time of an unstable slope can be roughly estimated prior to failure. A GIS model that combines fuzzy theory and the analytical hierarchy process (AHP) was developed to assess slope instability in open-pit coal mines. This model simultaneously considers seven factors that influence the instability of open-pit slopes (i.e., overall slope gradient, slope height, surface flows, excavation plan, tension cracks, faults, and water body). Application of the proposed method to an open-pit coal mine revealed an enhanced prediction accuracy of failure time and failure site compared with existing methods.

• Economic and Environmental Geology
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• v.54 no.1
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• pp.91-103
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• 2021

In order to estimate the vertical and horizontal structural in the Yangsan fault core line (Naengsuri area, Pohang), we carried out gravity field measurements and interpretation procedures such as Euler deconvolution method and curvature analysis in addition to the forward modelling technique (i.e. IGMAS+). We found a prominent gravity difference of more than 1.5 mGal across the fault core. This indicates a distinct density difference between the western and eastern crustal area across the Yangsan fault line. Comparing this gravity field interpretation with other existent geologic and geophysical survey data (e.g. LiDAR, trenching, electric resistivity measurements), It is concluded that (1) the prominent gravity difference is caused by the density difference of about 0.1 g/㎤ between the Bulguksa Granite in the west and the Cretaceous Sandstone in the east side, (2) the fault core is elongated vertically into a depth of about 2,000 meters and extended horizontally 3,000 meters to the NNE direction from Naengsuri area. Our results present that the gravity field method is a very effective tool to estimate a three -dimensional image of the active fault core.

• Economic and Environmental Geology
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• v.14 no.2
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• pp.55-76
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• 1981

Southwestern contact zone of the Boeun granodiorite occurs near the thrust fault between the Ogcheon Group and Majeonri Limestone Formation. Ogcheon Group, metasediments composed of the Munjuri Formation, Changri Formation, and unconformably overlying Hwanggangri Formation, belongs to greenschist facies of regional metamorphism accompanied with deformation of two fold axes, $N10^{\circ}E$ and $N45-65^{\circ}E$ directions. Basic metamorphic rocks occurring in the Changri and Limestone Formations are the meta-basalts and meta-diabases of tholeiitic basalt series. The meta-basalts intruded in the Changri Formation as sills, whereas the meta-diabases in the Changri and Limestone Formations as stocks in appearance. They are considered to have emplaced before the formation of two fold axes and related with the thrust fault, based on the geologic setting of the area. The metamorphic facies are identified to be greenschist facies to epidote-amphibolite facies for the meta-basalt, and epidote-amphibolite facies for the meta-diabases. It is interpreted that such a variety of facies was related from the combination of earlier deuteric alteration and later regional metamorphism. The metasediments in southwestern contact zont of the Boeun granodiorite which is a product of later syntectonic intrusion of middle Jurassic in age, show pyroxene-hornfels facies near the contact and amphibole-horenfels facies away from the contact to the mineral zoning in the contact metamorphic aureole of the Limestone Formation, based on the paragenetic analysis of mineral assemblages. The Limestone in the area appears to be considerably $SiO_2-CaO-MgO-CO_2-H_2O$ can be adopted to evaluate equilibrium conditions of the mineral assemblages in each mineral zone. It is revealed that a temperature gradient was existed accross the contact aureole ranging from the higher igneous side to lower sedimentary side, whereas no clear trend of $XCO_2$ variation appears but high mole fraction. The tremolite diopside-quartz-calcite assemblages occurs in common through the most mineral zones of contact aureole that is in good agreement with the equivalent reaction curve which extends over a wide range of $T-XCO_2$ conditions.