• Title/Summary/Keyword: dolomite

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Geochemical Characteristics of Devonian Bitumen Carbonates in Alberta, Canada (캐나다 데본기 비투멘 탄산염암의 지화학적 특성 연구)

  • Kil, Young-Woo;Kim, Ji-Hoon;Choi, Ji-Young;Park, Myong-Ho
    • Economic and Environmental Geology
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    • v.45 no.4
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    • pp.365-375
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    • 2012
  • The objective of this study is to investigate inorganic characteristics of Devonian bitumen carbonates in Alberta using two drilling cores, Saleski 03-34-88-20w4 and Saleski 08-01-88-20w4, taken from the Core Research Center (CRC) of Canada. The bitumen carbonates are mainly composed of less than 0.2 mm dolomites and some carbonate includes small amount of quartz and calcite. The bitumen carbonates from two cores are interpreted to have formed in similar sedimentary environments and dolomitization processes. Carbonates from Saleski 03-34-88-20w4 core were formed under higher inflow of clastic sediment than those from Saleski 08-01-88-20w4 core. Range of crystallization temperature of dolomites in the both bitumen carbonate cores is about 40~$55^{\circ}C$. Dolomitizing fluid of the bitumen carbonates would be Devonian seawater. Bitumen carbonates from Cairn Formation, compared with the CRC cores, have experienced a similar crystallization temperature, but dolmititizing fluid of the bitumen carbonates from Cairn Formation have been modified from the isotopic exchange with continental crust.

Evaluation of Physical Property and Material Characteristics for Stained Glass in the Yakhyeon Catholic Church, Korea (약현성당 스테인드글라스의 재료학적 특성과 물성평가)

  • Cho, Ji Hyun;Lee, Chan Hee;Kang, Myeong Kyu
    • Journal of Conservation Science
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    • v.32 no.3
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    • pp.425-436
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    • 2016
  • The Yakhyeon catholic church (Historic Site No. 252 in Korea) that was constructed in 1892 has been the first western brick structure to ever have existed and one of the most important historical materials in the Korean modern architecture. After a fire had broken out at the catholic church in 1998, the stained glass on the back wall, the slab glass (dalle de verre) introduced by Lee Nam Guy in 1974, was repaired in 1999 because of singe scorch and water leakage. An analysis of the coloration elements showed that yellow, red and green included Zn, K and Cd, respectively. The glass of red contained Se, dark green contained Mn and Cr, and blue contained Pb and S. According to material analysis, the masonry joint was identified dolomite ($CaMg(CO_3)_2$) and calcite ($CaCO_3$), which was observed plate, columnar, rhombic and square of crystalline particles. Meanwhile, ultrasonic velocity in the stained glass recorded low speed in the middle and lower right of the window (an average of 4,130 m/s). And the joint was measured the lowest physical properties of the top left and middle of the window (an average of 2,053 m/s). This study have showed that extensive physical damage was founded to the left and middle rather than the right side. In this respect, more research in needed to conserve the correlation between color and physical properties.

Reduction Effects of Residual Pesticides using the Eco-friendly Soil Amendments in Agricultural Soil (환경친화적 토양개량제의 농경지 중 잔류농약 경감효과)

  • Lee, Hyo Sub;Hong, Su Myeong;Kim, Taek Kyum;Kwon, Hye Young;Kim, Dan Bi;Moon, Byeong Chul;Moon, Joon Kwan
    • The Korean Journal of Pesticide Science
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    • v.20 no.4
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    • pp.312-318
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    • 2016
  • This study investigated the reduction of residual pesticide in soil by using eight kinds of soil amendments such as shell, quick lime, dolomite, silicic acid, leaf mold, oil cake, bed soil and husk. A total of ten pesticides most frequently detected in agricultural soil were selected (azoxystrobin etc.) and soil amendments were treated in soils at a 2% application rate and incubated for 7 days. Pesticides were analyzed by HPLC-MS/MS with QuEChERS-based sample preparation procedure and pH was measured on 1, 3 and 7 days. This study showed that, soil amemdments were effective in reducing pesticides after 7days of incubation. Over 90% of azoxystrobin, cadusafos, chlorpyrifos, fluquinconazole, imidacloprid, isoprothiolane and procymidone were decomposed from soils amended with 2% quick lime, whereas the concentration of boscalid, dimethomorph and triycyclazole were not decreased. The soil pH increased to 12.8-12.9 in soil amended with quick lime, but other soil conditioners did not change the soil pH. Quick lime was particularly effective in reducing residual pesticides.

Mineral Compositions and Distribution in the Drilling Cores from the Miocene Pohang Basin, Korea (마이오세 포항분지 시추코어의 구성광물과 분포특성)

  • Lee, Jinhyun;Hwang, Jinyeon;Son, Moon;Son, Byeong Seo;Oh, Jiho;Lee, Hyomin
    • Journal of the Mineralogical Society of Korea
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    • v.30 no.3
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    • pp.113-126
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    • 2017
  • In order to investigate the geological storage potential of $CO_2$, X-ray diffraction analysis were conducted for drilling core samples collected from the two drilling sites located in Yonil group of the Miocene Pohang Basin. As a result, various minerals were identified such as quartz, plagioclase, orthoclase opal-CT, smectite, mica, illite, kaolin mineral, chlorite, calcite, gypsum, pyrite, dolomite, and siderite. Smectite was detected in almost all of core samples, and relatively large amounts of smectite were observed in the cores from deeper strata. Opal-CT, mainly occurred in the upper interval of cores, was formed by diagenesis of amorphous diatoms. It shows a tendency that d101 value of cristobalite decreases with depth from $4.10{\AA}$ to $4.05{\AA}$. The almost identical variations in mineral composition with depth are observed at the two sites. This fact indicates that rocks distributed at the two sites were probably deposited in the similar depositional environments. It is determined that the strata in the study area can play roles of cap-rock for $CO_2$ storage, because the considerable amounts of smectite were contained in the rocks through the cores.

Empirical Rock Strength Logging in Boreholes Penetrating Sedimentary Formations (퇴적암에 대한 경험적 암석강도 추정에 대한 고찰)

  • Chang, Chan-Dong
    • Geophysics and Geophysical Exploration
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    • v.7 no.3
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    • pp.174-183
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    • 2004
  • The knowledge of rock strength is important in assessing wellbore stability problems, effective sanding, and the estimation of in situ stress field. Numerous empirical equations that relate unconfined compressive strength of sedimentary rocks (sandstone, shale, and limestone, and dolomite) to physical properties (such as velocity, elastic modulus, and porosity) are collected and reviewed. These equations can be used to estimate rock strength from parameters measurable with geophysical well logs. Their ability to fit laboratory-measured strength and physical property data that were compiled from the literature is reviewed. While some equations work reasonably well (for example, some strength-porosity relationships for sandstone and shale), rock strength variations with individual physical property measurements scatter considerably, indicating that most of the empirical equations are not sufficiently generic to fit all the data published on rock strength and physical properties. This emphasizes the importance of local calibration before one utilizes any of the empirical relationships presented. Nonetheless, some reasonable correlations can be found between geophysical properties and rock strength that can be useful for applications related to wellhole stability where haying a lower bound estimate of in situ rock strength is especially useful.

Hydrogeochemistry of Groundwaters at the Gogum island area in Jeonnam, Korea (전남 고금도 지역 지하수의 수리지구화학)

  • Park, Cheon-Young;Ahan, Kun-Sang;Jeong, Youn-Joong;Shin, In-Hyun
    • Journal of the Korean earth science society
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    • v.23 no.6
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    • pp.474-485
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    • 2002
  • The object of this study is to investigate the contamination degree and the interpretation of sea water intrusion phenomena with hydrogeochemical and hydrogen-oxygen stable isotope of coastal aquifer in the Gogum area, Korea. The physical characteristics of groundwaters is the neutral pH condition and transitional Redox environments, and groundwater is affected by sea water & surface water. The chemical properties of groundwaters are showing an increase in contamination owing to the sea water intrusion, waste water from the surface and agricultural chemicals. In the case of chloride, 6 samples of the groundwater in the study area are in excess of the drinking water standard. The Piper diagram shows the contamination in GG-4 and 14 by sea water intrusion. GG-3, 7 and 13 dominate the Na-HCO$_{3}$ type water and regional (GG-14) is indicated to dominate the Na-Cl type water such as sea water. According to the Sl (saturation index), sea water is oversaturated with respect to calcite and dolomite, GG-3, 14 and 18 are approaching the saturation state. The hydrogen-oxygen stable isotope ratio of groundwaters originates in the meteoric water, and groundwaters of GG-1, 5 and 14 display high oxygen isotope value due to surface water trespass and sea water intrusion. The result of this study, GG-14 is contaminated by sea water intrusion, groundwaters expected GG-3, 7 and 13 is in progress to artificial pollution and sea water intrusion.

Mineralogical Characteristics of Calcite observed in the KAERI Underground Research Tunnel (고준위폐기물 지하처분연구시설(KURT)에서 관찰되는 방해석의 광물학적 특징)

  • Lee, Seung-Yeop;Baik, Min-Hoon;Cho, Won-Jin
    • Journal of the Mineralogical Society of Korea
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    • v.19 no.4 s.50
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    • pp.239-246
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    • 2006
  • KAERI Underground Research Tunnel (KURT) was recently constructed through the site investigation from the yea. of 2003 at KAERI site, Dukjin-dong, Yuseong-gu, Daejeon city. The geo-logic setting of the site has been slightly metamorphosed. There are small fractures developed in the rock and several kinds of secondary filling minerals exist in the fractures. We examined mineralogical characteristics of fracture-filling calcite, which is not only largely distributed, but also can significantly affect the radionuclides migration. The calcite is found along fractures like other secondary minerals, forming thick veins in part. Most calcite-filled fractures contain quartz, iron oxides, and dolomite as minor minerals. The calcite crystals show an characteristic appearance with an uniformly oriented growth, coated with goethite on the edge and the etch-pit sites of their surface. Some calcite crystals have been newly formed by the precipitation of elements dissolved from the tunnel shotcrete wall, and their morphology changed according to the chemistry and flow of groundwater. The calcite can modify the groundwater chemistry and significantly affect the sorption behavior of radionuclides. The characteristic crystal structure and surface morphology of the calcite examined in the KURT site will be used as important basic data for the radionuclide migration experiment in the future.

Occurrence and Mineralogy of Serpentine Minerals in the Calc-silicate Rock Sheets from the Bonghwa Area, Kyungsangbuk-do (경북 봉화지역의 석회규산염층에서 산출되는 사문석광물의 산상 및 광물학적 특성)

  • Bae, Sung-Woo;Hwang, Jin-Yeon;Lee, Son-Kap;Kwack, Kyu-Won;Yoon, Ji-Hae;Cho, Sung-Hwi
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.1
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    • pp.85-98
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    • 2008
  • Calc-silicate rock sheet occurs within the Precambrian metasedimentary rocks in Bonghwa area, Kyungsangbuk-do, Korea. The calc-silicate rock runs parallel to bedding plane with $14{\sim}18$ meters in width. Calcite, dolomite, serpentine and tremolite are occurred as major minerals and talc is occurred as a miner mineral. Serpentine mainly occurs in the upper part and tremolite occurs in lower part of calc-silicate rock sheet. Colors of calc-silicate rock change to deeper green with increasing amounts of serpentine mineral. XRD, FT-IR analyses indicates that serpentine mineral is antigorite. Platy structure of antigorite is well observed by SEM analysis. EPMA data indicates that chemical composition of antigorite is very close to ideal ($SiO_2$: 44.3 wt% and MgO: 40.8 wt%). The chemical formula of antigorite is calculated as $Mg_{2.82}Al_{0.04}Fe^{3+}_{0.04}Si_{2.05}O_5(OH)_4$. From careful study by comparing mineralogical analysis data and occurrence, calc-silicate rock sheet was formed by metamorphism of calcareous sedimentary rocks having different mineralogical and chemical compositions. It is considered that the host rock of serpentine enriched upper part was more Mg-rich rocks than the host rocks of tremolite enriched lower part.

Heavy Metal Contamination, Mineral Composition and Spectral Characteristics of Reddish Brown Precipitation Occurring at Osip Stream Drainage, Gangwon-do (강원도 오십천 수계에서 발생하는 적갈색침전물의 중금속 오염, 광물조성 및 분광학적 특성)

  • Lim, Jeong Hwa;Yu, Jaehyung;Bae, Sungji;Koh, Sang-Mo;Park, Gyesoon
    • Journal of the Mineralogical Society of Korea
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    • v.31 no.2
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    • pp.75-86
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    • 2018
  • This study analyzed precipitation environment, heavy metal concentration, mineral composition, and spectral characteristics associated with heavy metal concentration and mineral composition for the reddish brown precipitates occurred in the drainage of Dogye mining station. The pH of the reddish brown precipitates ranges from 7.59 to 7.94 resulting neutral. XRF analysis reveals that the precipitates has high Fe concentration, and contaminated with Ni, Cu, and Zn. Dolomite, calcite, goethite, magnetite, kaolinite, pyrophyllite, quartz and aluminum isopropoxide were identified based on XRD analysis. As a result of spectral analysis associated with heavy metal contamination, visible reflectance increases and infrared reflectance decreases with a increase in heavy metal concentration. The spectral characteristics of the reddish brown precipitates is turned out to be manifested by goethite, magnetite, kaolinite, pyrophyllite and aluminum isopropoxide.

Geochemical Characteristics of Devonian Cairn Formation in Alberta, Canada (캐나다 알버타 지역의 데본기 Cairn층의 지화학적 특성 연구)

  • Park, Myong-Ho;Kim, Ji-Hoon;Lee, Sung-Dong;Choi, Ji-Young;Kil, Yong-Woo
    • Economic and Environmental Geology
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    • v.43 no.2
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    • pp.85-100
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    • 2010
  • Devonian Cairn Formation is one of the important hydrocarbon reservoirs in Alberta, Canada. However, the Cairn Formation, outcropped in the study area, is not prospective reservoir with poor porosity and permeability by some late diagenetic processes. In this study, geochemical characteristics of the Cairn Formation were studied to use these preliminary results for advanced geological and geophysical petroleum explorations in the near future. Rock-Eval pyrolysis showed that total organic carbon content is less than 0.3 wt.%, indicating a minor amount of bitumen and/or other hydrocarbons. The carbonates in the Cairn Formation are mainly composed of subhedral and anhedral dolomites. Pore sizes in the carbonate are various, ranging from nanometer to micrometer. Clastic sediments increase in the upper and lower parts of the Cairn Formation, probably due to changing its depositional conditions. The Cairn Formation can also be divided into several intervals based on Ca/Mg ratio in dolomite and degree of amount of calcite. These could be formed by different sedimentary environment, degree of cementation and recrystallization, different saline/fresh water, etc.