• 제목/요약/키워드: Lithology

검색결과 163건 처리시간 0.023초

풍암퇴적분지 내 시추공 PABH1에서의 물리검층에 의한 암상의 판정 (Lithology Determination by Log Analysis from a Borehole-PABH1 in the Pungam Sedimentary Basin)

  • 김영화;장승익
    • 지질공학
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    • 제8권2호
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    • pp.163-173
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    • 1998
  • 강원도 홍천군 서석면 일대에 발달하고 있는 풍암퇴적분지 내에 위치한 시험시추공 PABH1에서 실시된 시추결과에 대한 암상판정과 동 퇴적분지의 구성암에 대한 물성반응의 특성을 확인하기 위하여 코어관찰과 코어의 물성측정, 그리고 지구물리검층을 실시하고 그 결과를 종합분석하였다. 시추공의 64미터와 124미터 구간에 걸쳐 정밀 코어관찰을 실시하고 11개 암상군으로 분류하였다. 코어 관찰결과 구분된 11개 그룹의 코어시료에 대하여 비저항, 자연감마 및 밀도를 측정하고 그 결과를 분석하였다. 지구물리검층 또한 비저항과 밀도, 자연감마곡선을 중점적으로 분석하여 암상판정을 시도하였다. 지구물리검층과 코어물성측정의 결 과에서 각 암상별로 특징적인 물성분포가 얻어졌으며 검층곡선만의 분석에 의해서도 암상의 구분이 충분히 가능할 수 있음을 보였다. 특히 이 지역에서의 조립질퇴적암과 세립질퇴적암, 그리고 퇴적기반인 화강편마암의 물성반응이 가장 현저하여 검층 해석에서 좋은 열쇄층의 역할을 할 수 있는 것으로 나타났다.

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백악기 경상분지의 생성 및 진화에 관여한 지구조운동의 분석과 최하부 낙동층에 대한 퇴적학적 연구 I: 경상분지 서남단 낙동층의 퇴적환경과 기원암, 고수류 분석 (Sedimentological Study of the Nakdong Formation to analyse the Forming and Evolving Tectonics of the Cretaceous Gyeongsang Basin, I: Depositional Setting, Source, and Paleocurrent Analyses of the Nakdong Formation in the Southwestern Gyeongsang Basin)

  • 정대교;김용인
    • 자원환경지질
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    • 제29권5호
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    • pp.639-660
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    • 1996
  • The lowest formation of the Cretaceous Gyeongsang Supergroup, the Nakdong Formation, unconformably overlies the gneiss complex basement in Hadong, Gyeongsangnam-do and Gwangyang, Chullanam-do. The Nakdong Formation of the study area is 500-600 m thick and occurs as a belt shape. Based upon lithology, sedimentary structure, and bedding geometry the formation consists of three conglomerate facies (Gd, Gn, Gic), five sandstone facies (Sh-n, Sh-i, Sp, Sr, Sm), and four mudstone facies (Mf, Mfn, Mc, Mv). Sandstone facies are the most prominent in the study area. The twelve facies can be grouped into five facies associations. The depositional settings are elucidated from analyses of 12 facies and five facies associations of the formation. The lower part of the Nakdong Formation was deposited in alluvial plain, and the middle and upper parts were in a riverine system. The lithologies of the Nakdong Formation of the Gyeongsang Basin have been considered to consist of generally conglomerates and pebbly sandstones that were accumulated in alluvial fans. But the common lithology of the study area is sandstone which was formed in lower part of alluvial fan or fluvial setting. It is supposed that the coarser sedimentary sequence distributed west to the study area should be eroded out after deposition and early uplift, and the finer sandstone sequence in the east remains behind. The mineral composition of sandstones and the clast composition of conglomerates indicate that the Nakdong Formation was derived mainly from the metamorphic source rocks. Some reworked intraclasts were also supplied from the intrabasinal sedimentary layers. Paleocurrent data collected from cross-beddings, ripple marks, asymmetric sand dune suggest that most sediments were transported from north to south during the Nakdong Formation time.

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다변량 통계 기법을 이용한 물리검층 자료로부터의 암석물리학상 결정 (Automatic Electrofacies Classification from Well Logs Using Multivariate Statistical Techniques)

  • 임종세;김정환;강주명
    • 지구물리와물리탐사
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    • 제1권3호
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    • pp.170-175
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    • 1998
  • 이 연구는 다변량 통계 기법을 이용한 물리검층 자료로부터의 암석물리학상 결정으로 암상을 예측하는 것이다. 기술 통계 분석으로 물리검층 자료의 특성을 파악하고 주성분 분석에 의한 다변량 검층 자료들의 상관도 분석을 통해 변수들을 변환시켜 새로운 변수인 주성분을 구하고 변수들의 차원을 축소한다. 통계적 방법에 의한 주성분 검층 자료의 구획에 의한 효율적 자료 축소와 계산의 효율성을 높여 양질의 해석결과를 얻을 수 있다. 구획된 주성분 검층 자료로부터 계보적 군집 분석에 의해 암석물리학상을 결정한다. 최적 암석물리학상의 수는 전체 변동과 군집내의 변동사이의 비와 코어자료 등에 의해 비교 결정된다. 이 연구에서 개발된 암석물리학상 결정법을 국내대륙붕 물리검층자료에 적용한 결과 결정된 암석물리학상은 시추 코어 및 시추 암편 분석에 의한 암상 구분화와 잘 일치하였다. 이러한 연구는 저류층 특성인자의 신뢰성 있고 정량적인 평가로 유전 개발 및 생산 계획 시 유용한 도구로 활용될 수 있을 것이다.

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AUTOMATED ELECTROFACIES DETERMINATION USING MULTIVARIATE STATISTICAL ANALYSIS

  • Kim Jungwhan;Lim Jong-Se
    • 한국석유지질학회:학술대회논문집
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    • 한국석유지질학회 1998년도 제5차 학술발표회 발표논문집
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    • pp.10-14
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    • 1998
  • A systematic methodology is developed for the electrofacies determination from wireline log data using multivariate statistical analysis. To consider corresponding contribution of each log and reduce the computational dimension, multivariate logs are transformed into a single variable through principal components analysis. Resultant principal components logs are segmented using the statistical zonation method to enhance the efficiency and quality of the interpreted results. Hierarchical cluster analysis is then used to group the segments into electrofacies. Optimal number of groups is determined on the basis of the ratio of within-group variance to total variance and core data. This technique is applied to the wells in the Korea Continental Shelf. The results of field application demonstrate that the prediction of lithology based on the electrofacies classification matches well to the core and the cutting data with high reliability This methodology for electrofacies classification can be used to define the reservoir characteristics which are helpful to the reservoir management.

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지구정보시스템을 이용한 충주호 북부 지역의 사면 안정 평가 (Analysis of Slope Stability Using GIS in the Northern Area of Chungju Lake)

  • 문상기
    • 자원환경지질
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    • 제33권1호
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    • pp.51-59
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    • 2000
  • As a part of natural hazard assessment, regional slope stability analysis was conducted using Geoscientific Information System (GIS) in the northern area of Chungju Lake. Selected factors which affect the slope stability in the study area were lithology, soil, density of lineament, groundwater level, dip of slope, aspect of slope, and geological engineering properties. Geological structural domains were determined by collected data of joint orientation from about 200 sites in order to produce a slope instability map. Potential type of failure and its direction could be expected through the domains. And a slope instability map was produced, comparing the representative orientations of the domains with the orientations of the slopes which were made through TIN module in ARC/INFO. Under the consideration of environmental geological characteristics of the study area, rating and weighting of each factor of slope stability analysis were decided and spatial analysis of regional slope stability was couducted through overlaying technique of GIS. The result of areal distribution of slope stability showed that the most unstable area was the area between Mt. Pudae and Mt. Jubong, and the northern area of the railway station, Samtan.

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문경지역에서 3차원 지반특성 분석연구 (3 Dimensional Geo-Information at Munkyeong area)

  • 이병주;황재홍;이창원
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.423-427
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    • 2010
  • To develope SOC(social overhead capita) which constructs the railroad, highway etc., the geo-technical foundation have to be well understood for the safety works. In this paper, we selected Moonkyung area for the study area, which has various geological units and geological structure including the big thrust and fold. By this reason one of the geo-technical information is the engineering geology map. To make the map, lithology and soil distribution with drilling data are important elements. Three dimensional geo-infomation is established by fence diagram which is several geological cross sections and/or computer software 3D Geomodeller, EarthVision, GSI3D, Gocad.

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APPLICATION OF LOGISTIC REGRESSION MODEL AND ITS VALIDATION FOR LANDSLIDE SUSCEPTIBILITY MAPPING USING GIS AND REMOTE SENSING DATA AT PENANG, MALAYSIA

  • LEE SARO
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.310-313
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    • 2004
  • The aim of this study is to evaluate the hazard of landslides at Penang, Malaysia, using a Geographic Information System (GIS) and remote sensing. Landslide locations were identified in the study area from interpretation of aerial photographs and from field surveys. Topographical and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. The factors chosen that influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature and distance from drainage, all from the topographic database; lithology and distance from lineament, taken from the geologic database; land use from TM satellite images; and the vegetation index value from SPOT satellite images. Landslide hazardous area were analysed and mapped using the landslide-occurrence factors by logistic regression model. The results of the analysis were verified using the landslide location data and compared with probabilistic model. The validation results showed that the logistic regression model is better prediction accuracy than probabilistic model.

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지진을 이용한 화산감시 (Volcano Monitoring Using Earthquakes)

  • 한아림;박이슬;김기영
    • 지구물리와물리탐사
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    • 제16권4호
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    • pp.268-274
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    • 2013
  • 마그마 또는 가스가 지하에서 이동함으로써 발생되는 화산지진의 연속적인 관측은 활화산 감시의 가장 중요한 방법 중 하나이다. 이 해설논문에서는 화산지진의 특징에 대해 살펴보았으며, 진원, 지진파형, 주파수, 암상 그리고 메커니즘에 따른 분류를 간단히 설명하였다. 또한 일본, 미국, 이탈리아, 뉴질랜드의 성공적인 분화 경보 사례와 화산지진 감시 실태를 소개하였다.

국내 낙석방지울타리의 적정성 파악을 위한 현장 실물 실험 및 설계기준 제시 (In Situ Rockfall Tests for Evaluation of Rockfall Protection Fences)

  • 구호본;박혁진;이경미;김규한;이재욱
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 가을 학술발표회 논문집
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    • pp.629-634
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    • 2000
  • Rockfall protection fence which is used for mitigation of rockfall hazard, has been constructed without consideration of lithology, height and dip angle of rock slope. However, those factors should be considered for the construction of the protection fence. In addition, the protection fence should be evaluated its performance by in-situ test in order to utilize the fence effectively. This is the first full sized rockfall test in Korea. For this test, the rock cut slope whose height is about 20 m and dip angle is 65 $^{\circ}$ has been chosen. Based on the preliminary simulation procedure, four different concrete balls (0.5 ton, 1.0 ton, 2.0 ton and 5.0 ton) were prepared and four different types of protection fence were constructed. The results of this test will be utilized in the establishment of rockfall protection fence construction manual.

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암반사면의 붕괴특성에 관한 연구(중앙고속도로를 중심으로) (A Study on the Failure Characteristics for the Rock Slopes (Centering Around Jungang Highway))

  • 김종렬;이진수;황평주;이용희
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.765-776
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    • 2005
  • As a result of industrial advancement and land development, a number of highway slopes have been gradually formed and numerous problems related to their stability have been frequently caused. Generally, major factors for rock slope stability are lithology, slope inclination, slope height, degree of weathering, precipitation, condition of groundwater and so onl. Many complex factors are mostly involved in the collapse of rock slopes. In this study, a database for 94 collapsed Jungang highway slopes were set up using GIS program through literature search, site investigation, geological map and Korea tectonic province map. The analyses for the collapsed factor including sort of rock(by origin), tectonic province, highway direction, slope gradient and direction, degree of weathering, slope height were carried.

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