• Title/Summary/Keyword: 지형형성작용

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Depositional Landforms in Jiwoo Drainage Basin (지우천 유역의 퇴적지형 연구)

  • Oh, In-Sun
    • Journal of the Korean association of regional geographers
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    • v.15 no.2
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    • pp.192-203
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    • 2009
  • The purpose of this paper is to elucidate the formative processes of depositional landforms in Jiwoo drainage basin which located in the most upstream reach of Namgang River. Through the analysis of morphologic characteristics and sedimentary facies, the formative processes can be summarized as follow: First, the high depositional landforms(Sapyeong, Eungam, Naedongdyttle site) were formed by gelifluction process in the periglacial environment during the last glacial period. And the relative height over river bed of them is getting lower from upper to downstream. The extent of the high depositional landforms is assumed about 1 kilometer downstream far from the confluence of Jiwoo stream and Namgang River. Second, the sediments in the gentle slope at Jangseungbuldle were carried by gelifluction process during the last glacial stage after the deep-weathered bedrock had formed a gentle slope. Third, the high depositional landforms were dissected during warm and humid environment of postglacial stage, and some sediments of them were left in the river bed. Later, as the more upstream high depositional landforms were dissected completely, stream power was getting more than resistance(sediment storage) and the low depositional landforms(Sapyeong, Yongchusa, Deungbangdle site) were formed.

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Geology and Soil Environment of Jangdo Wetland, Heuksan-myon, Sinan-Gun, Cheollanamdo-province: A preliminary study (흑산도 지역 장도습지의 지질 및 토양환경: 예비조사)

  • Heo Chul-Ho;Kim Seong-Yong
    • Journal of the Korean earth science society
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    • v.26 no.7
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    • pp.661-667
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    • 2005
  • It was preliminarily considered that Jangdo wetland was a concave landform formed by the weathering of granite intruding Precambrian silicified metasedimentary rocks. Various granite-weathered topography was observed. The formation scenario of Jangdo wetland is as follows. By flood or slope mass movement of regolith, rock fragments were moved to form a low-relief slope landform. As a result, wetland was formed. By analyzing the slope soil and wetland sediment, we conjectured that Jangdo wetland depended on the influence of peripheral slope soil. In these concavelandform environment, the supply of water and organic materials was sustained for a long time to form a organicnondegradable wetland environment. In addition, the plants appropriate to this wetland environment were settled to thicken the wetland. This is how the present Jangdo wetland was thought to be formed.

Concepts and Geomorphic Properties on Fluvial Terraces (하안단구의 개념과 지형 특성)

  • Lee, Gwang-Ryul
    • The Korean Journal of Quaternary Research
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    • v.25 no.1
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    • pp.1-13
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    • 2011
  • To reinterpret the meaning of fluvial terraces in the Quaternary researches, the concepts and geomorphic properties of fluvial terraces are reviewed. Fluvial terraces are the alluvial landform that was once river channel or floodplain by paleochannel flowed in elevated areas from the current river by active incision of rivers due to the climatic changes and/or uplifts. As fluvial terraces are the remnants of alluviums after incisions of rivers, the major factors influencing on the incisions are the falling of erosion base, increase of river discharge and distinct geomorphic phenomenon of river. While it is generally known that fluvial terraces deposits in the upper or middle reaches of large rivers were formed during glacial periods, the deposits may be formed at the various periods due to the diverse natural environments and geomorphic properties of specific rivers, because there have been numerous cases that the ages of fluvial terraces in the upper or middle reaches of large rivers in Korea and China can be correlated to the interglacial periods.

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우리 나라 동굴의 지질과 환경 보전

  • 정창희
    • Proceedings of the Speleological Society Conference
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    • 1996.09a
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    • pp.64-64
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    • 1996
  • 석회동굴은 카르스트 지형 지역에서 지하 형성물로 나타나는 공동지역으로, 이 공동화된 공간에 2차적으로 석순, 석주, 종유석 등이 침전되어 생긴 동굴이다. 이런 카르스트 지형은 석회암 지층에서 용식작용으로 생겨나는데, 우리나라에서는 북쪽은 평안남도 동반지역과 함경남도의 남부서경지역, 황해도 서남부, 그리고 강원도 남부지역, 추가령 구조곡의 일부들이 해당한다. 그리고 남쪽은 문경 - 단양 - 제천 - 영월 - 평창 - 정선 - 삼척 - 강릉에 걸친 지역들이다. 따라서 우리나라의 석회암동굴들은 그 대부분이 조선계 대석회암통의 막동 석회암 층에 분포되고 있다.(중략)

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Hydraulic Effect on Vegetation Behavior in the Sand Bar (사주에서의 식생거동과 수리 및 지형특성의 관련성)

  • Kim, Jin-Hong;Yang, Jeon-Young
    • Proceedings of the Korea Water Resources Association Conference
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    • 2006.05a
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    • pp.2016-2022
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    • 2006
  • 생태계에서 식생의 중요성은 식물이 일차적인 생산자로서의 역할뿐만 아니라 홍수 조절과 토양 등 지형의 여러 가지 환경요인을 변화시킨다. 일정 구간의 식물상과 식생분포는 그 하천의 환경요인과 밀접하게 연관되어 있으며, 환경요인의 변화에 따라 식물상과 식생도 영향을 받게 된다. 특히, 홍수 전 후에는 수중 및 수변에 분포하는 식물들에게 극히 민감하게 작용되고, 그 영향도 광범위하게 나타난다. 자연생태계에 있어 식생의 변화양상은 환경요인의 변화에 따라 달리 형성된다. 즉, 일정지역의 식물상과 식생은 지형, 토양(하상 입경의 크기), 수리 특성 등과 밀접하게 연관되어 있으며 이들 요인이 변하면 식물상과 식생도 영향을 받아 식물군락의 공간적 분포범위가 구별된다. 특히, 하천에서는 유수에 의한 지형 형성 과정이 역동적이며, 유수량과 수위의 계절적 변화가 심하여 식생의 구조, 공간적 분포가 다양하게 나타난다. 우리는 서울의 대표적인 도심 하천 중 하나인 도림천을 대상으로 조사하였다. 도림천을 4구간으로 홍수전($4{\sim}7$월), 홍수 후($8{\sim}10$월)로 나누어 월별로 식생의 분포와 거동특성, 수리 수질적인 특성에 대해 결과를 도출하였으며, 연구 결과를 통해 식생 별 하상입경의 변화와 하상변동, 세굴 및 퇴적 등을 분석하였다.

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The Morpho-Climatic Characteristics of Stratified Slope Deposits in the Southwest Region of Haenam (해남 남서부지역의 Stratified Slope Deposit의 기후지형학적 특성)

  • PARK, Chul-Woong
    • Journal of The Geomorphological Association of Korea
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    • v.15 no.2
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    • pp.11-24
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    • 2008
  • Stratified slope was formed on the SSE-facing slope in the southwest region of Haenam, South Korea. Field and laboratory investigations into the geomorphology and sedimentology of stratified slope deposit that is inactive. Outcrops of this deposit show an alteration of coarse debris-supported matrix and tiny debris-supported matrix layers. Sedimentological analysis(particle-size analysis) indicates that this deposit is not fluvial process or only gravitation like rock-fall. Many clasts and fine materials on the slope is supposed to be product by congelifraction under Pleistocene periglacial climatic environment. Also The processes responsible for the genesis of this deposit probably are to move downward by gelifluction and to remove fine materials by slope wash in thawing cycle and in situ debris congelifraction on gelifluction slope. Now It is impossible to account for the time range of genesis(diurnal, seasonal). In conclusion, this stratified slope formed in cold and humid periglacial environmental in pleistocene, therefore, this slope is a periglacial relic landform, indicates that in south korea there was a cold and humid paleo-climate such as periglacial environmen.

충청남도의 해안사구

  • 강대균
    • Proceedings of the KGS Conference
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    • 2003.05a
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    • pp.51-55
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    • 2003
  • 해안사구는 사빈으로부터 모래를 공급받아 형성되는 지형이다. 사빈은 조차에 비해 파랑의 작용이 활발한 해안에 발달한다. 해안사구는 일반적으로 모래의 공급이 풍부하고 바람이 탁월한 해안에 광범하게 발달된다. 우리나라와 같은 온난ㆍ습윤한 지방의 해안사구는 대부분 직생으로 덮여 있다. 식생은 해안사구의 발달을 돕는다. 사빈과 해안사구는 해수욕장으로 이용되어 자원으로서의 가치가 높다. (중략)

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Geomorphic Variables Influential to Develop Erosional Characteristics (산지사면의 침식에 영향을 주는 지형인자에 관한 연구)

  • Yoo-Jeong Hwang
    • Journal of the Korean Geographical Society
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    • v.33 no.3
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    • pp.365-376
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    • 1998
  • The goal of this study is to find the geomorphic variables contolling gully development on hillslopes following deforestation. Two possible geomorphic processes, surface erosion and mass movement were reviewed to compare the characteristics and geomorphic variables involved. The research objective in this paper is to find the variables and the statistical model which can explain gully density in the study area. Gully density was selected as a response variable. For log gully density, the best subset regression was found to have the variables such as area, surface length, and surface width. Log area is the most significant predictor. Even with several outliers, the normal probability plot of the residuals from this regression looks straight. So, area, surface length, and surface width explain half of the variance in gully density.

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Human Responses as Landscape Indicators of the Place Vulnerability (장소 취약도에 대한 경관지표로서의 인간의 대응)

  • HAN, Joo-Yup;LEE, Min-Boo
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.1
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    • pp.109-121
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    • 2012
  • Human responses, such as construction of levees, are a spatial representation of the place vulnerability which is induced by a geomorphic hazard like flooding. Human responses include all forms of human activities to reduce the place vulnerability and they seem to be related with reducing vulnerability rather than reducing geomorphic hazards. Diverse human responses to the perceived environment bring about changes in the place vulnerability. People respond spatially to their vulnerability of the place in diverse ways from their experience and perceived risk. Human responses have quantitative possibilities in predicting and modeling the place vulnerability. Building the model of a dynamic place vulnerability to the diverse geomorphic hazards requires basic maps of geomorphic processes and human responses in the region.

A Study on the Indexes and Properties of Mechanical Weathering to Granite Distributed in Korea (화강암의 풍화산물에 대한 기계적 풍화지수의 특성에 관한 연구)

  • Rheem, Chong-Ho
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.99-111
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    • 1993
  • The transformation of rocks into unconsoli-dated debris is the prime geomorphic processes including weathering and soil forming process. In these processes, rocks tend to be unconsol-idated debris with small particles. Particularly, typical granite is more likely affected by weathering, since the rock consists of quartz, feldspar and mica that can be easily coarse-grained and well jointed without bedding. The purposes of this study are to clarify the index and properties of mechanical weathering that contributed to transformation of granite distributed in Korea. A total of seventy-three samples of weathering products of granite in Korea were collected during the three-year period, March 30, 1989 to February 21, 1992. The prticle analysis was performed for clay, silt and sand using Sieve and Hydrometer. The results of the analysis are as the followings: First, soil textures in the study area are included seven categories of textures as C, CL, SCL, Sil, SL, LS, and S. Among these textures, the most frequent soil texture were SL, S and SCL in order. Second, the weathering products of granite are crumbled by weathering and hydrothermal. Clay texture consisted of fine materials seems to be influenced by hydrothermal, while Sand texture composed of coarse materials, seems to be significantly influenced by weathering. Third, the index of mechanical weathering by region indicates that Hawngdeung(1) is the lowest as 2.37 and the index by soil texture shows that Clay texture is the lowest as 2.46. Forth, the regression analysis of MW showes that sand/clay variable is the most significant variable. Finally, pedochemical weathering is prevailed on the clayey gruss and geochemical weathering is on the gruss and shattering is on the weathered rock, strongly, but the fine materials in some sites were formed by argillation of hydrothermal.

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