• Title/Summary/Keyword: 구릉대

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Weathering Characteristics of Granitic Grus in Naesung Stream Drainage, Yeongju-Bonghwa Basin, Korean Peninsula (내성천 유역분지인 영주-봉화 분지 화강암 구릉대의 풍화 특색)

  • Kim, Youngrae;Kee, Keundo
    • Journal of The Geomorphological Association of Korea
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    • v.21 no.4
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    • pp.97-108
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    • 2014
  • Naesung stream famous for 'sandy river', a tributary to the Nakdong River, flows through Yeongju-Bonghwa Basin, its drainage. If the dismantlement of granitic hills in basin is in final stage, weathering materials from hills into stream are finer materials like silty or sandy loam than coarse sand, because sand as weathering mantles is provided from granitic hills, in general. So the granitic hills in Yeongju-Bonghwa basin is dissecting present. As a results of the CIA analysis(A-CN-K and A-CNK-FM ternary diagram), chemical weathering of granitic grus in Yeongju-Bonghwa basin is too very weak for calcium and sodium to be dissolved and go as far as to be more weak than that of Jeongeup, Nonsan and Namwon, common granitic grus in Korean Peninsula. Therefore, the chemical characteristics of granitic hills in Yeongju-Bonghwa basin show that the alteration of weathering mantles just finished disintegration and is dissected at a standstill. Plenty of sands provided from granitic hills is filling the channel of Naesung stream.

Morphology and Ecological Milieu of Keum-gae River basin in Andong Province (안동 금계천 유역의 지형과 생태 환경)

  • KEE, Keun-Doh
    • Journal of The Geomorphological Association of Korea
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    • v.17 no.4
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    • pp.99-110
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    • 2010
  • This study elucidates the interrelationship between climatic, morpological, and hydraulic milieu in the drainage basins of Keum-gae river from the viewpoint of ecogeography. The region of this basin is located at low-relief hills. Because hills are made up of granitic regolith by deep weathering, the rate of permeability is very high. And, the speed of drainage is very fast, and the deficit of water easily revealed and BOD is very high. Therefore a great deals of efforts are needed for the maintenance of stable milieu.

Chemical Weathering Trend and Rubefaction of Granitic Hills in Naju, Southern Korea (한반도 남서부 나주 일대 화강암 구릉대의 적색화와 화학적 풍화 경향)

  • Kim, Young Rae
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.1
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    • pp.57-68
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    • 2012
  • Red saprolites are appeared in granitic hills in Naju, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with kaolinitic saprolites of Guadalquivir Basin in Spain formed under paleo-humid tropical conditions. Chemical Index of Alteration(CIA) value for Naju in Korea is 80, and 87 in Guadalquivir, suggesting moderate and strong weathering in both. Relative to kaolinitic saprolite of Guadalquivir in Spain, red saprolites in Naju are commonly weak loss of CaO, $Na_2O$, especially in $K_2O$. The A-CNK-FM ternary plots of Naju saprolites relative to Kaolinitic saprolites of Guadalquivir shows weak chemical alteration owing to slow removal of $K_2O$, but high mafic constituents, $Fe_2O_3$ and MgO, for most of the samples. In the saprolites of Naju, mafic oxides, $Fe_2O_3$ and MgO, become enriched because of the fast and massive removal of CaO, $Na_2O$ and $K_2O$ relative to other elements, resulting in rubefaction of the surface layer of the saprolites, so more redness than kaolinitic saprolites of Guadalquivir. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

Geomorphological Environment of Suwon Basin (수원 분지의 지형 환경)

  • Kee, Keun-Doh;Lee, Sang-Whan
    • Journal of the Korean association of regional geographers
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    • v.10 no.2
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    • pp.300-312
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    • 2004
  • The geomorphological environment of Suwon Basin consists of two great elements: mountains which surround the basin and plains and low relief hills by differential erosion of granitic area. Nothern and eastern parts of the basin surround with gneissic mountains(Mt. Kwangkyo), southern and western parts of the basin with granitic mountains(Mt. Chilbo, etc). The basin developed on granitic saprolites is composed of two types of sub-order geomorphic elements: flood plains alongside four river(Whangkuji-chon, Seoho-chon, Suwon-chon, Wonchonri-chon) and aligned hills and mounts between the river side plains. While the low down lands provided the spatial condition for the extention of downtown of Suwon, the gneissic mountains have played the positive roles by high ecological dam effects with stable supply of water and purification of air, etc.

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Chemical Weathering Characteristics of Red Saprolites at Granitic Hills in Yeongam, Southwestern Korea (한반도 남서부 영암의 화강암 구릉대 적색토의 화학적 풍화 특색)

  • Kim, Young-Rae
    • Journal of the Korean Geographical Society
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    • v.47 no.3
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    • pp.315-327
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    • 2012
  • Red saprolites are appeared in granitic hills in Yeongam, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with laterite profiles in Cameroon formed under humid tropical conditions. The red saprolites in Yeongam show commonly massive loss of CaO, $Na_2O$, but $K_2O$ is being slow. The red saprolites in Yeongam relative to laterite and kaolinite profiles of Cameroon and Spain show weak chemical alteration owing to slow removal of $K_2O$, but high mafic constituents, $Fe_2O_3$ and MgO, for most of the samples. In the saprolites of Yeongam, mafic oxides become enriched because of the fast and massive removal of alkali constituents, such as CaO, $Na_2O$ and $K_2O$, relative to other elements, resulting in rubefaction of the saprolites. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

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Weathering Characteristics of Granitic Regolith in Southern part of the Korean peninsula (한반도 남부의 화강암 구릉대 지표피복물의 풍화 특색)

  • KIM, Youngrae;KEE, Keundo;YANG, Jaehyuk
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.4
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    • pp.123-137
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    • 2012
  • Reddish superficial materials in southern area of Korean Peninsula have been defined as lateritic red soil in Korea. In A-CN-K ternary plots, CaO and $Na_2O$ show similar linear distribution along a A-K line to kaolinite profile and laterite in southern Spain and Cameroon, respectively, and it means strong alteration. But $K_2O$ is weak alteration, plotting between muscovite and illite zone. Granitic reddish weathering mantles in study area show bulk distribution in center when plotted in A-CNK-Fm space, in contrast to laterite in Cameroon, plotting linearly in the middle along a A-FM line. Therefore, alteration of reddish saprolites in Southern Korea have not progressed as much as laterite. To define Reddish saprolite in southern Korean Peninsula as a lateritic red soil, more many studies are necessary.

Granite Landforms in the Vicinity of Seungil-gyo Bridge at Cheorwon, Central Korea (철원군 승일교 인근의 화강암 지형 경관)

  • LEE, Min-Boo;HAN, Joo-Yup;KIM, Chang-Hwan
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.4
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    • pp.27-37
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    • 2012
  • This study investigated granite landforms formed by Hantan-gang fluvial erosion and deposition, or by weathering in the area neighboring the Seungil-gyo bridge in Cheorwon-gun Gangwon-do Korea, in which the contact zone of Myeongseongsan granite and Cheorwon lava plateau creates a unique landform. Major granite landforms are deeply weathered hill, sheet erosional landform, paleo-landform surface and paleosoil, micro-fluvial landforms such as pothole and groove, granite rampart, sand bar and boulder bar, former riverbed. And river cliffs on a weakly weathered dome act as a barrier to lateral shifting of the river.

Temporal-Spatial Location of Dwelling Site in Asan Bay in the Neolithic Age (아산만지역(牙山灣地域) 신석기시대(新石器時代) 집자리의 시공적(時空的) 위치(位置))

  • Koo, Ja Jin
    • Korean Journal of Heritage: History & Science
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    • v.42 no.3
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    • pp.26-47
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    • 2009
  • This study examined dwelling site from among the sites of the Neolithic age found in the Asan Bay(牙山灣) area, and the temporal-spatial location and meaning of the dwelling site (settlement). The majority of the settlements in the area are of a square style but some coexist with rectangular-style settlements, which is noteworthy. The dwelling sites of the Neolithic age found in Asan Bay area are mostly located in a ridge of hilly areas, divided into gentle, low areas (20~50 meters above sea level) and relatively high areas (50~80 meters above the sea level). Although location strongly corresponded to the residents' subsistence and the technical levels within the culture, it likely was greatly affected by natural environment where they lived, as well. In examining radiocarbon dating results and the excavated artifacts, the settlements found in Asan Bay were determined to belong to the period II(3,500~3,000 B.C.) stated in the Relative Chronological table of Dwelling sites in the Neolithic age, written by the author. Said Dwelling sites are proven to have a close relationship with those found on the coast of Gyeonggi Province(京畿道) and in the Geum River(錦江) valley. This is deemed to be the result of expansion and interchange between Gyeonggi Province(京畿道) group and Geum River(錦江) valley group, who constituted the large settlements. Additionally, the Daecheon-ri type dwelling sites in the Geum River valley were verified to be the result of exchange, and spread to the Asan Bay area in the same era. Two forms of Dwelling sites coexisted dynamically in the Asan Bay area around 3,500 B.C. Such a phenomenon resulted primarily from the expansion of the dwelling site due to the introduction of primitive agriculture, as well as environmental (temperature), biological and social changes at those times.

The study changes of the settlement structure on Bronze Age in Yongdong area (영동지역 청동기시대 취락구조의 변천)

  • Park, Yeong-Gu
    • KOMUNHWA
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    • no.69
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    • pp.5-40
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    • 2007
  • The research against Youngdong area Bronze Age settlement structure the condition where the investigation against the area and the remains which are limited becomes accomplished and Only the dwelling site will be investigated from the early settlement of most and recognition there is not a possibility which it will investigate synthetically. The Early settlement to the time which reaches the size of the settlement is small and From Bangnae-ri phases the house possession area increases inside the hill and it follows on south and if dwelling site numbers under increasing, from the aspect where the size of the settlement is magnified seems and it is a position. The Middle settlement currently was confirmed as the beginning from the room village A ruins, it investigates a settlement structure to, the increase of data is necessary. Is Pottery with clay stripes, phases the Later Settlement which Dwelling site, Storeage, Earthenware Kiln, Ditch enclosure and Tomb, the Public dwelling site back large scale Pottery with clay stripes settlement of formation will be investigated from Bangdong-ri settlements which correspond to Songhyun-ri settlement which is a hill characteristic settlement which is located in rivers circumference and the higShland characteristic settlement to provide the data the cultural aspect and character and a settlement structure of Bronze Age postscript and it will be able to grasp.

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Geomorphological Environment of Daejeon Basin and Its Influence Urbanization (지형을 중심으로 한 대전 지역의 이해)

  • Kee, Keun-Doh;Lee, Min-Ho
    • Journal of the Korean association of regional geographers
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    • v.8 no.2
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    • pp.229-246
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    • 2002
  • This study is a contribution to the geographical understanding of Daejeon Area, playing the role of principal center of Choongchong Province. This area has been urbanized associated with Daejeon Basin, an important natural unit in the middle part of South Korea. In order to understand Daejeon Area in geographer's view, it is necessary to elucidate geomorphological environment of Daejeon Basin and urban expansion pattern associating with it. Our research is converged into dual objectives: one, description and interpretation of basin's landforms; other, urban expansion relating with geomorphological condition. Daejeon's urban expansion has progressed from the border zone of Daejeon Basin toward into the basin, and then vice versa. Relating to rivers valleys in the basin, the urbanization in the basin has been extended from the river valleys of lower order toward those of higher order. Understanding of the geomorphological mosaique of Daejeon basin is an important base for that of urban mosaique of Daejeon City.

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