• Title/Summary/Keyword: structural geology

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Geologica Structure of the Euiseong Sub-basin by Anlaytic Aeromagentic Anomaly Data (항공자력의 Analytical 이상을 이용한 의송소분지의 지구조 연구)

  • 김원균
    • Economic and Environmental Geology
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    • v.33 no.3
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    • pp.229-237
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    • 2000
  • The structure of Euiseong Sub-basin and boundary of sub-basins were examined by analytical aeromagentci anomaly data. Magnetic lineaments have trends of NE-SW, NWW-SEE and NEE-SWW. The NE-SW lineaments in the sedimentary formations and pre-Cretaceous basement are assoicated with the direction of expansion of basin and the lineaments in the volcanic rocks and intrusives indicate the direction of structural weakness ones such as fault, which were major gateways of igneous activities. Euiseong Subbasin is bounded by pre-existing Andong Fault, pre-Cretaceous basement in the west, NE-SW lineament from Jyungsan to Angang, and NW-SE lineament connecting southwestern boundary of Palgongsan Granite and Jeokje Fault. In particular , the NW-SE lineament , which caused upheavel of pre-Cretaceous rocks, on Jeokje Fault is inferred as a boundary between Euiseong and Milyang Sub-basins.

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Analysis of Slope Stability by Using Remote Sensing and GIS in Ichon Basin (원격탐사와 지구정보시스템 (GIS)을 이용한 이천분지의 사면안정평가)

  • Won, Jong Suck;Lee, Young-Hoon
    • Economic and Environmental Geology
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    • v.30 no.3
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    • pp.241-248
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    • 1997
  • In this study, Ichon basin is selected as study area and regional analysis of geological structure are done by using lineament analysis. The factors which affects slope stability, are chosen, and integrated to database using GIS (Geoscientific Information System). Landsat TM band 4, 5 and 7 are choosen and processed by various image enhancement technique to analyse the regional geological lineaments. Spatial distribution of lineament is analysed through lineament density map and study area can be divided the eight structural domains. Considering environmental geological characteristics of study area, rating and weighting of each factors for slope stability analysis are determined and spatial analysis of regional slope stability is examined through overlaying technique of GIS. The result of areal distribution of slope stability shows that the most unstable area is all over Mt. Buksung, Mt. Daepo, Mt. Songrim and Mt. Yankak.

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Determination of Hypocenter Parameters Using a Personal Computer (개인용 컴퓨터에 의한 지진의 진원인자 결정)

  • Kim, So Gu;Kim, Tae Woo
    • Economic and Environmental Geology
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    • v.25 no.3
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    • pp.359-365
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    • 1992
  • The parameters of the Korean earthquake have been determined by the manual method, which results in consuming more time and more errors. In this study we used HYPO71PC to determine earthquake parameters and to identify unknown active faults and lineaments in South Korea. The epicenters determined by the new computer technique are almost identical with the manual method of Korea Meteorological Agency. It is also found that most of epicenters are coincident with unknown faults that are defined as the un-determined faults on the tectonic map of Korea, and/or structural lineaments in South Korea.

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Regulation of Macrophage Ceruloplasmin Gene Expression: One Paradigm of 3'-UTR-mediated Translational Control

  • Mazumder, Barsanjit;Sampath, Prabha;Fox, Paul L.
    • Molecules and Cells
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    • v.20 no.2
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    • pp.167-172
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    • 2005
  • Ceruloplasmin (Cp) is a copper protein with important functions in iron homeostasis and in inflammation. Cp mRNA expression is induced by interferon (IFN)-${\gamma}$ in U937 monocytic cells, but synthesis of Cp protein is halted after about 12 h by transcript-specific translational silencing. The silencing mechanism requires binding of a 4-component cytosolic inhibitor complex, IFN-gamma-activated inhibitor of translation (GAIT), to a defined structural element (GAIT element) in the Cp 3'-UTR. Translational silencing of Cp mRNA requires the essential proteins of mRNA circularization, suggesting that the translational inhibition requires end-to-end mRNA closure. These studies describe a new mechanism of translational control, and may shed light on the role that macrophage-derived Cp plays at the intersection of iron homeostasis and inflammation.

Blastability Quality System (BQS) for using it, in bedrock excavation

  • Christaras, B.;Chatziangelou, M.
    • Structural Engineering and Mechanics
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    • v.51 no.5
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    • pp.823-845
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    • 2014
  • Success in the excavation of foundations is commonly known as being very important in asserting stability. Furthermore, when the subjected formation is rocky and the use of explores is required, the demands of successful blasting are multiplied. The quick and correct estimation of excavation's characteristics may help the design of building structures, increasing their safety. The present paper proposes a new classification system which connects blastability and rock mass quality. This new system primarily concerns poor and friable rock mass, heavily broken with mixture of angular and rounded rock pieces. However, it should concern medium and good quality rock mass. The Blastability Quality System (BQS) can be an easy and widely - used tool as it is a quick calculator for blastability index (BI) and rock mass quality. Taking into account the research calculations and the parameters of BQS, what has been at question in this paper is the effect of BI magnitude on a geological structure.

A two-step interval risk assessment method for water inrush during seaside tunnel excavation

  • Zhou, Binghua;Xue, Yiguo;Li, Zhiqiang;Gao, Haidong;Su, Maoxin;Qiu, Daohong;Kong, Fanmeng
    • Geomechanics and Engineering
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    • v.28 no.6
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    • pp.573-584
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    • 2022
  • Water inrush may occur during seaside urban tunnel excavation. Various factors affect the water inrush, and the water inrush mechanism is complex. In this study, nine evaluation indices having potential effects on water inrush were analysed. Specifically, the geographic and geomorphic conditions, unfavourable geology, distance from the tunnel to sea, strength of the surrounding rock, groundwater level, tidal action, cyclical footage, grouting pressure, and grouting reinforced region were analysed. Furthermore, a two-step interval risk assessment method for water inrush management during seaside urban tunnel excavation was developed by a multi-index system and interval risk assessment comprised of an interval analytic hierarchy process, fuzzy comprehensive evaluation, and relative superiority analysis. The novel assessment method was applied to the Haicang Tunnel successfully. A preliminary interval risk assessment method for water inrush was performed based on engineering geological conditions. As a result, the risk level fell into a risk level IV, which represents a section with high risk. Subsequently, a secondary interval risk assessment method was performed based on engineering geological conditions and construction conditions. The risk level of water inrush is reduced to a risk level II. The results agreed with the current tunnel situation, which verified the reliability of this approach.

The Deformation Properties and their Formative Processes in Ogcheon Terrain around Ogcheon Town, North Chungcheong Province, Korea (옥천대(沃天帶)의 변형특성(變形特性)과 그 형성(形成) 과정(過程) -충북(忠北) 남서단(南西端)을 예(例)로 하여-)

  • Lee, Byung-Joo;Park, Bong-Soon
    • Economic and Environmental Geology
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    • v.16 no.2
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    • pp.111-123
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    • 1983
  • The studied area is situated in tho southern part of the Ogcheon fold belt, where the "Ogcheon Group" is widespread with Jurassic and Cretaceous intrusions. The regional stratigraphy may be divided into three formations, the lower pebble bearing phyllitic, the middle dark grey phyllitic, and the upper black phyllitic formations. For the purposes of the present study, the area has been partitioned to three structural subareas based on major fold axes and fault line. The main subjects of the research have been discussed from two different points, multiple deformation and minor-micro fold styles. The former is analyzed by pebble elongation, folding and lineation in a pebbly formation as well as schistosity, crenulation cleavage and crenulated lineation in the phyllitic formation. The later describes the characteristic features of fold style in each formation and structural subarea. Although minor fold axes within broad pelitic rocks usually tend to trend northeast and to plunge northward, most of these were probably formed by two stages, first a similar fold phase and second a kink fold phase. Measured structural elements indicate that crenulation cleavage in phyllite formed parallel to fold axes of folded pebble followed a NE phase of first deformation and a fold axes of pebbles diagonal to bedding of phyllite are represented by a NW phase of a second deformation. Microscopically, quartz and mica grains form a micro fold enabling one to establish tectonic levels which occur in different deformation modes in each stratigraphic sequence. Microtextures such as crenulation cleavage, kink band, aggregate band of mica and pressure shadows of porphyroblast of quartz related to qarnet and staurolite may suggest the time relation of crystallization and tectonism. The result of this study may conform that three deformation phase, NE first phase-NE second phase-NW phase, occurred in the area.

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Strategy for Improving the Resolution of Electrical-resistivity Inversions for Detecting Soft Ground at Shallow Depths (~ 10 m) (천부(약 10 m) 연약 지반 탐지를 위한 전기비저항 역산 해상도 향상 전략)

  • Jang, Hangilro;Song, Seo Young;Kim, Bitnarae;Nam, Myung Jin
    • The Journal of Engineering Geology
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    • v.28 no.3
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    • pp.367-377
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    • 2018
  • This study introduces a DC resistivity inversion method that incorporates structural and inequality constraints to enhance the resolution of resistivity inversions, and presents sample inversion results with these constraints. In the constrained inversions, a base model is constructed from a layered model through interpretation of other geophysical data. Inversion tests establish that both the structural and inequality constraints produce better resistivity models than the unconstrained inversion. However, the inequality inversion not only reproduces the exact layered structure of the background, it reproduces conductive anomalies at a depth of ~ 10 m when an inexact base model of electrical resistivity is used.

Theory of NMR Spectoscopy and Its Application in Geoenvironmental Sciences (NMR 분광법의 원리와 지구환경과학에의 응용)

  • 김영규
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.233-245
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    • 2001
  • With the advent of super-conducting magnet, NMR spectroscopy becomes a very important tool in geology as well as in chemistry. $^{29}Si$ and $^{27}Al$ which are the main components of minerals and contain structural informations, are useful major targets for the NMR study in geology, but some other elements including alkali cations such as $^{23}Na$ are also one of them. NMR can be applied to many different fields. For example, it can be applied to study smaller range of structure (in molecular level) than XRD and TEM. NMR provides us with structural informations such as order-disorder in Al and Si distribution, oxygen coordination number, and distribution of other cations. Another important information that we can obtain from NMR is not only the static structural informations, but also the molecular dynamics. This dynamic informations of molecules also enable us to figure out the frequency of molecular motion and activation energy. Structure of amorphous minerals and chemistry and structure of natural organic materials are also studied by NMR.

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Possibility for Heliotropism from Inclined Columns of Stromatolites, Socheong Island, Korea

  • Kong, Dal-Yong;Lee, Seong-Joo
    • Journal of the Korean earth science society
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    • v.34 no.5
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    • pp.381-392
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    • 2013
  • Socheong island is a unique island containing Precambrian stromatolites in South Korea. Most of Socheong stromatolites are domes and columns, occurring as 10 cm to 1 m thick stromatolite beds. Lower parts of the stromatolite beds are predominantly composed of domes, but columns increase toward the upper level of stromatolite beds. In many of the stromatolite beds, inclined columns are easily identifiable, which is generally considered as a result of heliotropism. From general lithology, sedimentary structures, inclined angles and distributional pattern, and structural deformation of sedimentary rocks of Socheong island, the inclination of Socheong stromatolites could be better interpreted as a secondary structural deformation probably after formation of stromatolite columns, rather than as a result of heliotropism. However, at this moment, we do not clearly reject heliotropism interpretation for inclined columns of Socheong stromatolites. This is because the original position of stromatolite columns could have been lost if structural deformation had affected the whole sedimentary rocks of Socheong island.