• Title/Summary/Keyword: landform

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The Study on the Debris Slope Landform in the Southern Taebaek Mountains (태백산맥 남부산지의 암설사면지형)

  • Jeon, Young-Gweon
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.77-98
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    • 1993
  • The intent of this study is to analyze the characteristics of distribution, patter, and deposits of the exposed debris slope landform by aerial photography interpretation, measure-ment on the topographical maps and field surveys in the southern part Taebaek mountains. It also aims to research the arrangement types of mountain slope and the landform development of debris slopes in this area. In conclusion, main observations can be summed up as follows. 1. The distribution characteristics 1)From the viewpoint of bedrocks, the distribution density of talus is high in case of the bedrock with high density of joints, sheeting structures and hard rocks, but that of the block stream is high in case of intrusive rocks with the talus line. 2)From the viewpoint of bedrocks, the distribution density of talus is high in case of the bedrock with high density of joints, sheeting structures and hard rocks, but that of the block stream is high in case of inrtusive rocks with the talus line. 2) From the viewpoint of distribution altitude, talus is mainly distributed in the 301~500 meters part above the sea level, while the block stream is distributed in the 101~300 meters part. 3) From the viewpoint of slope oriention, the distribution density of talus on the slope facing the south(S, SE, SW) is a little higher than that of talus on the slope facing the north(N, NE, NW). 2. The Pattern Characteristics 1) The tongue-shaped type among the four types is the most in number. 2) The average length of talus slope is 99 meters, especially that of talus composed of hornfels or granodiorite is longer. Foth the former is easy to make free face; the latter is easdy to produce round stones. The average length of block stream slope is 145 meters, the longest of all is one km(granodiorite). 3) The gradient of talus slope is 20~45${^\circ}$, most of them 26-30${^\croc}$; but talus composed of intrusive rocks is gentle. 4) The slope pattern of talus shows concave slope, which means readjustment of constituent debris. Some of the block stream slope patterns show concave slope at the upper slope and the lower slope, but convex slope at the middle slope; others have uneven slope. 3. The deposit characteristics 1) The average length of constituent debris is 48~172 centimeters in diameter, the sorting of debris is not bad without matrix. That of block stream is longer than that of talus; this difference of debris average diameter is funda-mentally caused by joint space of bedrocks. 2) The shape of constituent debris in talus is mainly angular, but that of the debris composed of intrusive rocks is sub-angular. The shape of constituent debris in block stream is mainly sub-roundl. 3) IN case dof talus, debris diameter is generally increasing with downward slope, but some of them are disordered and the debris diameter of the sides are larger than that of the middle part on a landform surface. In block stream, debris diameter variation is perpendicularly disordered, and the debris diameter of the middle part is generally larger than that of the sides on a landform surface. 4)The long axis orientation of debris is a not bad at the lower part of the slope in talus (only 2 of 6 talus). In block stream(2 of 3), one is good in sorting; another is not bad. The researcher thinks that the latter was caused by the collapse of constituent debris. 5) Most debris were weathered and some are secondly weathered in situ, but talus composed of fresh debris is developing. 4. The landform development of debris slopes and the arrangement types of the mountain slope 1) The formation and development period of talus is divided into two periods. The first period is formation period of talus9the last glacial period), the second period is adjustment period(postglacial age). And that of block stream is divided into three periods: the first period is production period of blocks(tertiary, interglacial period), the second formation period of block stream(the last glacial period), and the third adjustment period of block stream(postglacialage). 2) The arrangement types of mountain slope are divided into six types in this research area, which are as follows. Type I; high level convex slope-free face-talus-block stream-alluvial surface Type II: high level convex slope-free face-talus-alluvial surface Type III: free face-talus-block stream-all-uvial surface Type IV: free face-talus-alluval surface Type V: talus-alluval surface Type VI: block stream-alluvial surface Particularly, type IV id\s basic type of all; others are modified ones.

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Arctic and Subarctic Karst Landforms in North America

  • Oh, Jongwoo
    • Journal of the speleological society of Korea
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    • v.42 no.2
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    • pp.7-16
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    • 1995
  • Karst in Arctic and Subarctic region in North America contains a wide variety of surficial karst landform characteristics due to not only extensive glacial activities, but also interglacial karst processes during the Pleistocene age.(omitted)

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A Study of Regional Geomorphology in the Chugaryeong Tectonic Valley, Central Korea (추가령 구조곡의 지역지형 연구)

  • Lee, Min-Boo;Lee, Gwang-Ryul
    • Journal of the Korean Geographical Society
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    • v.51 no.4
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    • pp.473-490
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    • 2016
  • This study aims to analyze the regional geomorphology of the Chugaryeong Tectonic Valley which has been one of the most important areas for Korean geomorphological research. Though the Chugaryeong Tectonic Valley has been thought important for the tectonic settings and orographic processes in Korea, geomorphological and geological discussions still are sustaining for finding out evidences of the settings. The Chugaryeong valley region has many geomorphic themes such as tectonic structure, volcanics, river, mountain, terrace, lake and sediment layers. The research of the valley focuses on the comprehensive analysis of the previous references mainly including geomorphic naming, geomorphology and geology, and history of the study for estimating the origin of tectonic valley, formation of the lave plateau, change of river structure by dissection, restoration of the landform before lava eruption, and the processes and age dating of the various landforms. Conclusively, the Chugaryeong Tectonic Valley may be recognized as the linear region of the tectonic and volcanic landforms with other various applied geomorphic settings.

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Behaviour of Subsurface Water Flow on the 'U-shaped Gol' Head Hollow of Hillslope (호우시 구릉지 완사면에 발달된 'U자골' 곡두부에서의 지중수 거동)

  • Cho, Kyong-Min;Yang, Hea-Kun;Astunao, Marui;Park, Jong-Kwan
    • Journal of the Korean Geographical Society
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    • v.41 no.6 s.117
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    • pp.670-681
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    • 2006
  • The purpose of this study is to clarify the behavior of subsurface water flow during rainfall on the hillslope in the Dongguneung experimental basin. As a result of the study, the following conclusions were obtained. Under the total rainfall of 20mm, there were no groundwater level changes. However, it was found that total rainfall amount and rainfall intensity were important factors to change groundwater level in hilly slope. Also the rainfall duration and preexisted rainfall amount were important factors to change it on the head hollow. To analyze the modification of 'U-shaped Gol' landform, the pattern of return flow and through flow have to check during storm events. The microgeomorphic change of head hollow is based on the pattern of subsurface water flow.

An Epistemology of Geomorphology and An Ontological Approach to Geomorphology Education (지형 지식의 인식론적 특성과 존재론적 지형 교육)

  • 송언근
    • Journal of the Korean Geographical Society
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    • v.37 no.3
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    • pp.262-275
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    • 2002
  • The purpose of this paper is to suggest a particular approach to geomorphology education based on an epistemology (anti-realist of geomorphology knowledge. Anti-realist epistemology of geomorphology may be characterized by the belief that (1) geomorphology knowledge is made or constructed rather than discovered, (2) knowledge construction begins with the perception of meaningfulness of the landform, and (3) it means recognizing the given land in terms of shape or form; (4) the construction is, in other words, a subjective or inter-subjective interpretation by the perceivers; (5) knowledge develops along with the hermeneutic circles. Aims of geomorphology education according to this epistemology, may be (1) to have children not so much construct geomorphology knowledge as live the very construction, (2) to have children maintain an enduring interest in their surrounding landform, and (3) to have them appreciate the intimate connections between the landform of a region and the modes of living in that region. In short, aims of geomorphology education may have to be ontological, i.c., to have children engaged in the understanding as a process of living rather than for the resulting knowledge.

Growth Pattern and Species Composition by Landform and Seaside Distribution of Peucedanum japonicum Thunb. Community Group in Korea (갯기름나물 군락군의 해안과 지형 별 종조성 및 생육양상)

  • Song, Hong-Seon;Cho, Woo
    • Korean Journal of Environment and Ecology
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    • v.21 no.1
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    • pp.74-81
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    • 2007
  • This study investigated the growth pattern and species composition by landform and seaside distribution to evaluate the basic community structure and topographical distribution of the Peucedanum japonicum Thunb. community group in Korea. The appearing plants with the Peucedanum japonicum Thunb. were a total 170 taxa belonging to 130 genera and to 57 families, and the species number by families was the most in Compositae of 30 taxa. The frequency of appearing plants was the highest in the Aster spathulifolius Max.(54.1%), and the east and west seasides were the highest in the Aster spathulifolius Max. and south seaside was the highest in the Miscanthus sinensis Ander.. The ratio of common plants among seasides was the highest between the west and south seasides of 35.6% with 47 taxa. The distribution landforms of the Peucedanum japonicum Thunb. was a $17.4^{\circ}$ slope of the unevenness landform, vertical joint, horizontal joint, blockfield, planation surfaces and the rocky seaside of the sea cliff. The distribution among landforms was the greatest in the rocky seaside of the 61 regions. The sociability on growing pattern was the highest in the 3 sociability rank of 54.6% with the 83 region.

A Study on the Symbol Making for Mapping Landform of Elements (지형요소 지도화를 위한 기호제작에 관한 연구)

  • Kim, Nam Shin;Cho, Yong Chan;Oh, Seung Hwan;Kwon, Hye Jin
    • Journal of the Korean association of regional geographers
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    • v.20 no.3
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    • pp.245-255
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    • 2014
  • There is limitation to represent forms and internal process of topography if using simple symbols for geomorphic landscape in the cartography. One of the alternative method to find a solution to these problems is to use association symbol to imagine real landscapes through map reading. This study suggested making method of association symbols to describe geomorphic landscapes effectively. Landforms are not static objects but dynamic pedogenesis and morphogenesis one. It should be consider form, process, and material to make landform mapping, and also, make landform symbols by considering scalable changeability for point-polygon, line-polygon, point-line by scale. As a results, this study expected to help applications for geomorphology as well as environments, ecology, archaeology, and civil engineering etc.

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The Coastal Geomorphology in General of Korea - Research Trends and Issues - (한국의 지형학 연구 - 해안지형 일반 -)

  • Kim, Sung Hwan
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.1
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    • pp.1-15
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    • 2012
  • The purpose of this study is to review research trends and issues of coastal geomorphology in general of Korea, which is divided into two periods; the former and later periods of 1990s when The Korean Geomorphological Society was established. In this study, coastal geomorphology in general refers to the landforms except tidal flats and coastal terraces. The descriptive statistics of research papers published in 5 major geography journals since 1990s were computed and these papers were classified according to their main subjects. The methodology for coastal landform study was analyzed by sub-fields of landform change and sediment analysis. The study of coastal geomorphology in Korea started from around 1970s and has progressed significantly in terms of the scope and the number of papers published since 1990s. There is few paper published in 1990s on coastal geomorphology in general, but so many research has achieved and came to be the major part of coastal geomorphology study since 2000s. Further methodology is necessary for morphodynamics study in the future.

Extraction of the Talus Distribution Potential Area Using the Spatial Statistical Techniques - Focusing on the Weight of Evidence Model - (공간통계기법을 이용한 애추 분포 가능지역 추출 - Weight of evidence 기법을 중심으로 -)

  • Yu, Jaejin;JANG, Dong-Ho
    • Journal of The Geomorphological Association of Korea
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    • v.21 no.4
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    • pp.133-147
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    • 2014
  • Reducing the range of target landform, is required to save the time and cost before real field survey in the case of inaccessible landform such as talus. In this study, Weight of Evidence modeling, which is a Target-driven spatial analysis statistics methods, has been applied to reduce the field survey range of target landform. In order to apply the Weight of Evidence analysis, a likelihood ratio was calculated on the basis of the result of correlation analysis between geomorphic factors and GIS information after selection of geomorphic factors regarding talus. A best combination, which has the biggest possibility for Talus Potential Index, was found by using SRC and AUC methods after calculating the number of cases for each thematic maps. This combination which includes aspect, geology, slope, land-cover, soil depth and soil drainage factors, showed quite high accuracy by 74.47% indicating the ratio of real existent talus to potential talus distribution.