• 제목/요약/키워드: shales

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Mineralogy and Geochemistry of Shale Deposits in the Lower Anambra Basin, Nigeria: Implication for Provenance, Tectonic Setting and Depositional Environment

  • Olugbenga Okunlola;Agonsi Udodirim Lydia;Aliyu Ohiani Umaru;Raymond Webrah Kazapoe;Olusegun G. Olisa
    • 자원환경지질
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    • 제56권6호
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    • pp.799-816
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    • 2023
  • Mineralogical and geochemical studies of shales within the Lower Anambra Basin was conducted to unravel the depositional environment, provenance, maturity, paleo-weathering conditions, and tectonic settings. Mineralogical studies conducted using X-ray diffraction analysis revealed that the samples were composed of kaolinite, montmorillonite, chlorite, and illite. KaolinIite is the dominant mineral, constituting approximately 41.5% of the bulk composition, whereas the non-clay minerals are quartz, ilmenite, and sillimanite. Geochemical analysis showed a predominance of SiO2, Al2O3, and Fe2O3 contents of the shale samples with mean values of 52.29%, 14.09%, and 6.15% for Imo Shale (IS); 52.31%, 16.70%, and 7.39% for Mamu Shale (MS); 43.21%, 21.33%, and 10.36% for Enugu Shale (ES); 53.35%, 15.64%, and 7.17% for Nkporo Shale (NS); and 51.24%, 17.25%, and 7.78% for Agwu Shale (AS). However, the shales were depleted in Na2O, MgO, K2O, MnO, TiO2, CaO, and P2O5. The trace element ratios of Ni/Co and Cu/Zn of the shale suggest an oxic depositional environment. The average SiO2 vs. Al2O3 ratio of the shales indicated textural maturity. Compared to the PAAS standard, the shales plot below the PAAS value of 0.85, suggesting a high degree of maturity and intensive chemical weathering, further confirmed on a CIA vs. PIA plot. On log (K2O/Na2O) against SiO2 and tectonic setting discriminant function diagrams, the shales plot mostly in the field of passive continental margin tectonic setting. The discriminant function diagrams as well as Al2O3/TiO2 ratio of the shales showed that they were derived from a mixed source (mafic and intermediate igneous rocks).

앙골라분지 백악기 흑색셰일의 유기물상 (Kerogen Facies of the Cretaceous Black Shales from the Angola Basin (DSDP Site 530), South Atlantic)

  • 박영수
    • 한국해양학회지
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    • 제22권2호
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    • pp.87-104
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    • 1987
  • 앙골라분지 심해시추연구(DSDP) 정점 530에서의 중기 백악기층은 유기탄소의 함량이 풍부한 흑색셰일과 유기탄소의 함량이 빈약한 적색 및 녹색의 점토암이 주 기적으로 교호한다. 이들 흑색셰일층의 퇴적환경을 밝히기 위하여 이들 중에 함유 된 불용성퇴적 유기물(Kerogen)의 종류 및 그 분포에 관하여 분석하였다. 앙골라분 지 백악기 흑색셰 일층에 함유된 유기물의 종류는 대부분 무정형유기물(Amorphous Organic Matter)로서, 이들의 주된 기원은 부유성 해양 조류. 즉 화석화되지 않은 해양 부유성 쌍편모충류로 추정되었다. 이들 부유성 조류는 환경의 변화에 따라 주 기적으로 다량 번식하여 앙골라 심해저로 공급됨으로써 , 백악기 당시 용존산소의 농도가 현재보다 훨씬 낮고 폐쇄된 환경의 앙골라 심해저에 환원환경을 주기적으로 야기시켜 유기물의 집적을 용이하게 함으로써 흑색셰일층이 형성되었음이 추측된 다.

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금산(錦山) 대성탄철지성(大成炭鐵地城) 산성폐수(酸性廢水)에 의한 오염(汚染) (Pollution by Acid Mine Drainages from the Daeseong Coal Mine in Keumsan)

  • 송석환;민일식;김명희;이현구
    • 자원환경지질
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    • 제30권2호
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    • pp.105-116
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    • 1997
  • This study is for extent of polluted area by acid mine drainage from the Daeseong coal mine, Keumsan. Black shales of the Changri Formation containing the Daeseong coal mine are geochemically similar to those from the North America as well as Europe. Comparing with geochemical compositions and relative ratios, coal bearing and non-coal bearing soils are similar to the stream sediments influenced and not influnced by the acid mine drainage, respectively. These characteristics suggest that acidification of the soils and of the stream sediments are related to the the coal bearing black shale. Soil waters beneath the coal bearing soil have low pH and high cation contents than those beneath non-coal bearing soil, suggestive of extractions of cations with increasing oxidizations within the soils. Surface waters show that those influenced by the acid mine drainage are low pH, and have high $SO_4{^{2-}}$, $Mg^{2+}$, $Fe^{2+}$, Mn and slightly lower DO, suggesting that heavy pollutions have been progressed in these area. Geochemical comparisons between the polluted surface water and adjacent black shales suggest that pollutions of the surface water are related to the black shales.

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Chemical Compositions and Pyrolysis Characteristics of Oil Shales Distributed in Korea

  • Yang, Moon Yul;Yang, Myoung Kee;Lee, Sang Hak;Wakita, Hisanobu
    • 분석과학
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    • 제8권4호
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    • pp.487-492
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    • 1995
  • The chemical compositions and pyrolysis characteristics of oil shales and source rocks distributed in the southwestern and southeastern parts of the Korean peninsular have been investigated. In order to compare the results of Korean samples with those of shales giving high oil yields, two Colorado oil shale samples and one Paris source rock samples were also investigated. Chemical compositions of the samples were analysed by means of gravimetry, CHN analysis, X-ray diffraction method, inductively coupled plasma atomic emission spectrometry and atomic absorption spectrometry. A custom made pyrolyser and a Rock-Eval system were used for the pyrolysis studies. Pyrolyses of the samples were carried out by means of a temperature controlling device to $600^{\circ}C$ at a heating rate of $5^{\circ}C/min$ with a helium flow rate of $1200m{\ell}/min$. The results of pyrolysis study indicated that Colorado shale samples belong to type I and all the other samples belong to type II.

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함탄층(含炭層) 내의 chiastolite-shale의 개발(開發) 이용(利用)에 관(關)한 연구(硏究) (The Research on the Exploitation and Utilitization of Chiastolite bearing shale in the Coal bearing strata)

  • 김옥준;김규한
    • 자원환경지질
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    • 제8권3호
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    • pp.135-146
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    • 1975
  • The chiastolite bearing shale was known to occur in various coal fields in South Korea among which the Kangneung coal fields is the most outstanding in quality and quantity of chiastolite. The chiastolite occurs mostly in black shales of Sadong formation and little in shales of Hongjom and Kobangsan formations, and is most abundant in the footwall coaly shales of the Sadong coal seams. The chiastolite has been proved to be thermal contact product of the high aluminous shale that comes into contact with Kangneung granite. The distribution of chiastolite in the Kangneung coal field is irregular. The eastern part of the region contains more chiastolite than that of western part. It is believed that the difference of the grade is due to the intensity of metamorphism. The grade of chiastolite in the shale varies from few percent up to as high as 60 % in volume, and the minable reserve of the chiastolite is estimated about 4,700,000 tons. This reserves is rather concentrated in few localities such as in Jiam Mine, Jungrim Mine, Sir 1 Hang in the Whasung Mine, the second and third sections of Kangneung Mine and Umbuelri district. The chemical composition of chiastolite bearing coaly shale is $SiO_2$, 35.0%; $Al_2O_3$, 27.0%; $Fe_2O_3$, 0.29%.

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한반도 남서부 중생대 백악기 함평퇴적분지의 고퇴적환경연구 (Palaeodepositional Environment of the Cretaceous Hampyeong Basin, Southwestern Korea)

  • 유환수;;고영구;윤석태;김주용;김해경;정철환;류상옥
    • 한국지구과학회지
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    • 제21권6호
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    • pp.683-694
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    • 2000
  • 중생대 백악기 함평분지의 고퇴적환경과 지질연대를 지화학, 암상 분포, 퇴적암석학 그리고 고식물학 측면에서 재고찰을 시도하였다. 연구 결과는 함평분지가 하성과 호성층으로 구성된 구조적으로 활동적인 분지였음을 시사한다. 이 분지에서는 주변 지형과 관련되어 분명한 환경 변화를 시사하는 산성응회암류, 흑색 셰일/사암상, 적색층, 응회암질 역암을 포함하는 중성응회암류 등 4가지 암상이 인지되었다. 구조적 운동에 수반하여 일어난 화산활동이 이들 퇴적층을 형성시킨 퇴적물을 주로 제공하였을 것이다. 이들 퇴적층들은 인접한 해남분지와 잘 대비된다. 그리고 화산성 기원의 퇴적물들은 유천층군에 해당하는 능주층의 경우와 유사하다. 분지 내에서 흑색 셰일의 광역적인 분포는 혐기성 환경 하에서 퇴적이 이루어졌음을 지시한다. 이들 암층에 있어서의 유기탄소의 함량(0.81%에서 1.75%)은 석유근원 셰일의 평균치 정도로 나타났다. 식물화석은 흑색셰일과 사암에서 산출된다. Platanoid류 잎 화석의 산출은 이들 퇴적층이 Oishi의 피자식물 계열 지층에 해당하며 시대상 Aptian/Albian 또는 보다 신기 지층임을 시사한다.

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한반도 중부권 지각물질의 구조와 물성연구(2) : 퇴적암류 코아시료의 탄성파 속도와 점재하 강도 비교 (Structure and physical properties of Earth Crust material in the Middle of Korean Peninsula(2) : Comparison between elastic Velocity and point-load of core specimen of sedimentary rocks.)

  • 송무영;황인선
    • 지질공학
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    • 제3권1호
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    • pp.21-37
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    • 1993
  • 석회암, 사암과 셰일의 퇴적암 코아시료를 대상으로 암석의 비중, 공극률, 함수율 등을 구하고 탄성파 전파 속도와 점재하 강도 지수를 측정하였다. 이들 암석물성 사이의 관계로부터 석회암에 대한 밀도와 탄성파 속도의 관계는 $Vp=4085d^2-20747d+303,{\;}V_s=3899d^2-21442d+318$의 다소 곡선 경향을 나타낸다. 또한 밀도가 높은 셰일의 탄성파 속도가 사암에서보다 작으며 이는 셰일의 층리 영향띠문인 것으로 보인다. 석회암, 사암, 셰일의 P파 속도와 S파 소ㄷ도는 대체로 직선 양상을 보여주며 각 관계식은 석회암에서는 $V_s=0.26V_p+1041.6m/sec,{\;}사암은{\;}V_s=0.43V_p+424.2m/sec$, 셰일에서는 r= 0.86으로 나타났다. 석회암에 대한 점재하 강도 시험에 의하면 점재하 강도 이방성을 시료가 다소 호상구조를 보이더라도 뚜렷하지 않았다. $30^{\circ}-60^{\circ}$내외의 변화를 보이는 층리면 경사각은 직경방향과 축방향의 점재하 지수에 큰 영향을 미치지 않은 것으로 생각된다. 점재하 강도 실험결과 점재하강도 지수가 증가하면 P파 속도도 증가하지만 상관관계가 뚜렷하지 않았다.

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확인코어공이 현장타설말뚝의 선단지지력에 미치는 영향 (Effect of verification core hole on tip capacity)

  • 윤희정
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.435-441
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    • 2010
  • In this study, numerical simulations were carried out to investigate the effect of verification core hole on the shaft tip capacity. The verification core extreted at shaft tip may deteriorate the shaft tip capacity when the clay shales (Taylor Marl) surrounding the shaft degrades and the empty core hole remains unfilled. Series of finite element analyses were conducted using Mohr-Coulomb model with total stress material parameters that were obtained from laboratory testing. The numerical analyses indicate that the shaft tip capacity does not decrease for most cases, and the maximum reduction does not exceed 5%.

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시멘트 원료로서 폐.부산자원의 활용 (Utilization of Waste and Industrial Byproducts as a Raw Material in the Manufacture of Portland Cement)

  • 최상흘;박용완;지정식;오희갑
    • 한국세라믹학회지
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    • 제15권3호
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    • pp.149-156
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    • 1978
  • The utilization of waste and industrial byproduct materials, such as blast furnace slag, shales, poor coal and anthracite briquet ash, were investigated as a source of calcareous or argillaceous material in the manufacture of Portland cement. As a slag is similar to cement in chemical compoment and contains about 40∼50% of CaO, it's utilization in cement manufacture should be suitable. The burnability was increased and the heat of clinker formation was decreased by using slag. Some consideration should betaken in the use of large quantity because of sticking in suspension preheater kiln. Suitable quantities of colliery shales and poor coal should be useable in cement manufacture as a argillaceous materials and also its combustible materials should be utilized in cement manufacture. Anthracite briquet ash is also usable as a argillaceous source and it gives good burnability.

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구속압에 따른 셰일의 이방성 거동 (Anisotropic Behavior of the shale with Confined Pressure)

  • 서인식;김동락
    • 한국산업융합학회 논문집
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    • 제8권2호
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    • pp.77-84
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    • 2005
  • Foliated metamorphic, stratified sedimentary and regularity jointed rocks have properties(physical, mechanical) that vary with direction (${\beta}^{\circ}$) and are said to be anisotropic. The ground in Daegu area consists of shales, clastic sedimentary rocks. These shales have plane anisotropic or transversely isotropy characteristics. Engineering characteristics of shale in Daegu area are investigated by performing a series of rock test to the bedding(${\beta}$ =0, 30, 60, and 90 degrees). The results of tests show that the uniaxial compressive strength is a maximum at ${\beta}$ = 0, $90^{\circ}$ and is a minimum when ${\beta}$ is around 60 degree.

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