• Title/Summary/Keyword: 지형발달사

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Lateral Migration Features of the Alluvial Channels in Hapyeong Intake Station, Nakdong River (해평취수장 부근에서 충적하천의 저수로 이동 특성)

  • Jang, Chang-Lae;Lee, Gang-Man;Kim, Gye-Hyun
    • Journal of Korea Water Resources Association
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    • v.41 no.4
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    • pp.395-404
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    • 2008
  • It is important to understand the complex, various migration features of the alluvial channels for river engineering. In this study, the morphological changes and migration features of alluvial channels were investigated by analyzing the aerial photographs of active channels between 1972 and 2004 in Hapyeong Intake Station, Nakdong river. The lower channels were migrated from left bank to right bank and showed the features of braided channel in 2004. The instability of lower channels was increased due to the increased channel slope and width. The sinuosity of lower channels was decreased with time. As time increased, the increasing rate of lower channel and lateral migration rate were decreased. As a result of meso-scale regime analysis by using bankfull discharge, multiple row bars were developed, and suspended sediment load was governed in the flow as a sand bed channel.

Geologic Structure of the Anatolian Peninsula: Tectonic Growth of Collisional Continental Margins (아나톨리아 반도의 지질구조: 대륙 충돌에 따른 구조적 성장)

  • Ryu, In-Chang
    • Economic and Environmental Geology
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    • v.45 no.4
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    • pp.465-476
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    • 2012
  • The Anatolia peninsula consists of several continental fragments that include the Pontide Block in north and the Anatolide-Touride Block in south as well as the Arabian Platform in southeast. These continental blocks were joined together into a single landmass in the late Tertiary. During most of the Phanerozoic these continental blocks were separated by paleo-oceans, such as Paleo-Tethys and Neo-Tethys. The Pontide Block in north show Laurasian affinities, and was only slightly affected by the Alpide orogeny; they preserve evidence for the Variscan and Cimmeride orogenies. The Pontic Block is composed of the Strandja, Istanbul and Sakarya zones that were amalgamated into a single terrane by the mid Cretaceous times. The Anatolide-Tauride Block in south shows Gondwana affinities but was separated from Gondwana in the Triassic and formed an extensive carbonate platform during the Mesozoic. The Anatolide-Tauride Block was intensely deformed and partly metamorphosed during the Alpide orogeny; this leads to the subdivision of the Anatolide-Tauride Block into several zones on the basis of the type and age of metamorphism and deformation. The Arabian Platform in southeast forms the northernmost extension of the Arabian Plate that shows a stratigraphy similar to the Anatolide-Tauride Block with a clastic-carbonate dominated Palaeozoic and a carbonate dominated Mesozoic succession. A new tectonic era started in Anatolia Peninsula in the Oligocene-Miocene after the final amalgamation of these continental blocks and plate. This neotectonic phase is characterized by extension, and strike-slip faulting, continental sedimentation, and widespread calcalkaline magmatism, which played a very important role in producing beautiful landscapes of the Anatolia Peninsula today.

The Development and Luminescence Chronology of a Coastal Dune from the Shindu Dunefield, T′aean Peninsula (신두리 지역의 전사구(前砂丘)에 대한 OSL 연대 측정 및 지형 발달)

  • Munyikwa Kennedy;Jong-Wook Kim;Jeong-Heon Choi;Kwang-Hee Choi;Jong-Min Byun
    • Journal of the Korean Geographical Society
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    • v.39 no.2
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    • pp.269-282
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    • 2004
  • Luminescence dating of a coastal dune from the Shindu dunefield on the T'aean Peninsula shows that deposition of the dune structure began about 500-600 years ago. The lower section of the dune has remained stable since then but the upper part yields an age of about 30 years, suggesting reactivation or additional deposition since the 1970's. The two samples that were collected from the lower part of the dune at depths of 3.5 m and 2.0 m below the surface differ by an age interval of about 50-70 years. This indicates a net depositional rate of around 2.5 cm a year which is relatively slow for a coastal dune. Whilst only one dune structure has been dated for the time being and even though the dunefield was probably established much earlier in the Holocene, the OSL ages obtained demonstrate that some dunes in the area could be younger than 1000 years. Such chronologies point to a dynamic environment where the dune structures are not permanently fixed. Sedimentological properties of the dune sands are consistent with those of particles initially deposited under subaqueous conditions and then later transported by wind.

An Hwak's Recognition of 'Joseon' and 'Joseon Cheolhak' (안확의 '조선' 인식과 '조선철학')

  • Lee, Haeng Hoon
    • The Journal of Korean Philosophical History
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    • no.50
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    • pp.171-200
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    • 2016
  • The full-scaled study of Joseon conducted by Japan in the 1910s was part of its colonial policy, while the native Joseon studies against it contained political aspiration to recover the national rights and independence. Accordingly, the conceptual meaning of 'Joseon' varied according to its subject of speech. The establishment of modern nation-state failed along with the extinction of Korean Empire, but 'Joseon' was newly discovered within national ideology. It became a historical concept in which the experience of the past and the expectation toward the future could be united. The so-called 'Joseon Studies' was only limited to intellectuals in the academic circle, but 'Joseon' embraced the articulations from more various social agents. Furthermore, it is only natural that 'Joseon Studies' should be interpreted within the historical semantics of 'Joseon', considering the connection between concept and discourse. In his The History of Joseon Civilization, An Hwak encompassed the history from the times of ancient mythology to the contemporary times under the banner of 'Joseon'. Opposing Japanese distortion of history carried out in the name of historical positivism, he idealized Joseon history as comparable to that of the Western democracy. He extended the study of 'Joseon' into culture at large, foreshadowing a kind of Joseon philosophy. In his An Overview of Joseon Philosophical Ideas, the first description of 'Joseon philosophy' as an independent field, he proposed philosophy as one of three sources of pride in Joseon and asserted its uniqueness and originality compared to the West. It was an attempt to grasp the peculiarity of Joseon ideas from a perspective of the history of universal human civilization. He considered 'Jong'(倧) as an ideological foundation held from the ancient to the modern times, and the acceptance of Buddhism and Confucianism as beneficial to 'Joseon philosophy'. The birth of 'Joseon philosophy', the modern transformation of the traditional knowledge system, was an intellectual experiment to apply traditional knowledge to the modern disciplinary classification system.

Spatiotemporal Changes of the Sand Barrier using Marine Charts Analysis in the Nakdong River Estuarine (해도분석을 통한 낙동강 하구 사주 면적의 시.공간 변화)

  • Yoo, Chang-Ill;Yoon, Han-Sam;Ryu, Cheong-Ro;Lee, In-Cheol
    • Journal of Ocean Engineering and Technology
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    • v.20 no.6 s.73
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    • pp.54-60
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    • 2006
  • This study discusses characteristic of spatiotemporal changes of the sand barrier in the Nakdong estuarine for the last century, focusing on geomarphologic evolution and mobility of sand barriers in the view of coastal engineering. The Nakdong estuarine, the research subject, has a complexly changing natural environment by interaction between ground and marine elements such as ocean wave, tidal current, sediment, etc. Moreover, recently, unnatural geomorphologic changes (e.g., seaside reclamation, new harbor construction, etc.) has been radically increased in this area with increasing desire for coastal development. Because of this, its sand barrier has developed quite unstable condition. Therefore, to identify the development process of geomorphologic changes in this area, required is a close examination on historical characteristics of spatiotemporal changes of the sand barrier in relation to surrounding seaside reclamation and physical environmental changes. This study, based on the marine charts published in between 1927 and 1995 year, analyzes the length and area of the sand barrier for the last hundred years, and investigates the cause of the changes by looking into the change of water depth for the last two years and doing ocean-physical site observations. In conclusion, the sand barrier of the Nakdong estuarine expands toward the open sea by $7.4{\sim}26m$ in annual average, maintaining a fixed distance of $1,241{\sim}1.279m$, and its area is expected to increase about $2.8km^2$ annually. This is characterized by the wocean wave from the open sea and the discharge of Nakdong River.

Natural Heritage Values and Diversity of Geoheritages on Udo Island, Jeju Province (제주도 우도 지역 내 지질유산의 다양성과 가치)

  • Woo, Kyung Sik;Yoon, Seok Hoon;Sohn, Young Kwan;Kim, Ryeon;Lee, Kwang Choon;Lim, Jong Deock
    • Korean Journal of Heritage: History & Science
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    • v.46 no.1
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    • pp.290-317
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    • 2013
  • The objectives of this study are to investigate the natural heritage and scientific value of various geosites on Udo Island, and to evaluate the sites as natural monuments and as world natural heritage properties. Udo Island includes a variety of geoheritage sites. Various land forms formed during the formation of the Someori Oreum formed by phreatomagmatic eruptions. The essential elements for the formation of Udo Island are the tuff cone, overflowing lava and overlying redeposited tuff sediments. Various coastal land forms are also present. About 6,000 years B.C., when sea-level rose close to its present level due to deglaciation since the Last Glacial Maximum, carbonate sediments have been formed and deposited in shallow marine environment surrounding Udo Island. In particular, the very shallow broad shelf between Udo Island and Jeju Island, less than 20 m in water depth, has provided perfect conditions for the formation of rhodoids. Significant amounts of rhodoids are now forming in this area. Occasional transport of these rhodoids by typhoons has produced unique beach deposits which are entirely composed of rhodoids. Additional features are the Hagosudong Beach with its white carbonate sands, the Geommeole Beach with its black tuffaceous sands and Tolkani Beach with its basalt cobbles and boulders. Near Hagosudong Beach, wind-blown sands in the past produced carbonate sand dunes. On the northern part of the island, special carbonate sediments are present, due to their formation by composite processes such as beach-forming process and transportation by typhoons. The development of several sea caves is another feature of Udo Island, formed by waves and typhoon erosion within tuffaceous sedimentary rocks. In particular, one sea cave found at a depth of 10 m is very special because it indicates past sea-level fluctuations. Shell mounds in Udo Island may well represent the mixed heritage feature on this island. The most valuable geoheritage sites investigated around Udo Isalnd are rhodoid depostis on beaches and in shallow seas, and Someori Oreum composed of volcanoclastic deposits and basalt lava. Beach and shallow marine sediments, composed only of rhodoids, appear to be very rare in the world. Also, the natural heritage value of the Someori Oreum is outstanding, together with other phreatomagmatic tuff cones such as Suwolbong, Songaksan and Yongmeori. Consequently, the rhodoid deposits and the Someori Oreum are worth being nominated for UNESCO World Natural Heritage status. The designation of Someori Oreum as a Natural Monument should be a prerequisite for this procedure.

Distribution and properties of intertidal Surface Sediments of Kyeonggi Bay, West Coast of Korea (경기만 조간대 표층퇴적물의 분포와 특성)

  • LEE, CHANG-BOK;YOO, HONG-RHYONG;PARK, KYUNG-SOO
    • 한국해양학회지
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    • v.27 no.4
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    • pp.277-289
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    • 1992
  • Kyeonggi Bay, a macrotidal coastal embayment in the Yellow Sea coast of central korea, is fringed by vastly developed tidal flats. About 400 surface sediment samples were collected from the intertidal and subtidal zones of Kyeonggi Bay for a study of the sediment distribution pattern and the surface sediment characteristics of this environment. The kyeonggi Bay surface sediment becomes progressively finer in the shoreward direction, from offshore sand to shoreward silty sand and sandy silt. This shoreward-fining trend is repeated again on the tidal flat and, as a consequence, a grain-size break occurs near the low-water line which separates the intertidal area from the subtidal one. The intertidal and subtidal sediments differ from each other in textural characteristics such as mean grain size and skewness and this can be interpreted to result from differences in hydraulic energy and morphology between the two environments. The mineral and chemical compositions of the Kyeonggi Bay sediments are largely controlled by the sediment grain size. Smectite was nearly absent in the clay mineral assemblage of Kyeonggi Bay sediment. The contents of Co, Cu and Ni were high in the Banweol tidal flat, which suggests a continuous process of accumulation of these metals. the intertidal environment appears to respond rapidly to artificial coastal modifications, the effects of which should be taken into consideration when planning a dam construction or coastal reclamation.

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A Study on the Expansion Process of Vegetation on Sand-bars in Fluvial Meandering Stream (충적하천 사행하도에 발달한 사주에서의 식생형성 과정에 관한 연구)

  • Lee, Sam-Hee;Ock, Gi-Young;Choi, Jung-Kwon
    • Korean Journal of Environment and Ecology
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    • v.22 no.6
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    • pp.658-665
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    • 2008
  • One of the characteristics of fluvial river channel with sand bed-material is the existence of movable sand bars not occupied with vegetation. However, sand bars at the Hahoe's reach of the Nakdong River showing a double-meandering channel has been changed into expanding vegetation area. Moreover, sand material, in recent years, has stopped moving to downstream in channel and the number and area of bare bars which did not occupied by vegetation have been decreased. In order to find out the mechanism, we carried out the channel characteristics surveys such as hydro-geomorphologic, soil physio-chemical and vegetation surveys were conducted twice on autumn season in 2005,2006. The results so far achieved showed that the reduced discharge of transported sediment and duration of dry season might be critical factors for the spread of luxuriant vegetation. The vegetation area was significantly expanded by floods exceeding the subsequent dominant flow discharge. Furthermore, the expansion of vegetation area was highly correlated with the supply of organic matter, nutrients and alteration of soil texture by sediment deposition during the flooding event.

Changes in Distribution of Debris Slopes and Vegetation Characteristics in Mudeungsan National Park (무등산국립공원의 암설사면 분포변화 및 식생 특성)

  • Seok-Gon Park;Dong-Hyo Kim
    • Korean Journal of Environment and Ecology
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    • v.37 no.1
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    • pp.1-12
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    • 2023
  • We analyzed the distribution area of debris slopes in Mudeungsan (Mt. Mudeung) National Park by comparing aerial photos of the past (1966) and the present (2017) and identified the vegetation characteristics that affect the change in the area of the debris slopes by investigating the vegetation status of the debris slopes and the surrounding areas. The area of debris slopes in Mt. Mudeung appears to have been reduced to a quarter of what it used to be. Debris slopes here have decreased at an average rate of 2.3 ha/yr over 51 years by vegetation covers. Notably, most of the small-area debris slopes in the low-inclination slopes disappeared due to active vegetation coverage. However, there are still west-facing, south-west-facing, south-facing, and large-area debris slopes remaining because the sun's radiant heat rapidly raises the surface temperature of rock blocks and dries moisture, making tree growth unfavorable. Because of these locational characteristics, the small-scale vegetation in the middle of Deoksan Stony Slope, which is the broadest area, showed distinct characteristics from the adjacent forest areas. Sunny places and tree species with excellent drying resistance were observed frequently in Deoksan Stony Slope. However, tree species with high hygropreference that grow well in valleys with good soil conditions also prevailed. In some of these places, the soil layer has been well developed due to the accumulation of fine materials and organic matter between the crevices of the rock blocks, which is likely to have provided favorable conditions for such tree species to settle and grow. At the top of Mt. Mudeung, on the other hand, the forest covered the debris slopes, where Mongolian oaks (Quercus mongolica) and royal azaleas (Rhododendron schlippenbachii), which typically grow in the highlands, prevailed. This area was considered favorable for the development of vegetation for the highlands because the density of rock blocks was lower than in Deoksan Stony Slope, and the soil was exposed. Moreover, ash trees (Fraxinus rhynchophylla) and Korean maple trees (Acer pseudosieboldianum) that commonly appear in the valley areas were dominant here. It is probably due to the increased moisture content in the soil, which resulted from creating a depressive landform with a concave shape that is easy to collect rainwater as rock blocks in some areas fell and piled up in the lower region. In conclusion, the area, density of the rock blocks, and distribution pattern of rock block slopes would have affected the vegetation development and species composition in the debris slope landform.

예천군지역의 역사적 변천과정 -고지도와 지리지의 비교분석

  • 이한방
    • Proceedings of the KGS Conference
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    • 2002.05a
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    • pp.99-105
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    • 2002
  • 변화의 속도가 느려서 장기지속적인 전체사의 바탕을 형성하고 있는 지리적 환경에 대한 적응결과로서의 지표경관을 도면상에 표현한 고지는 당시대인들의 세계관과 공간인식을 반영하고 있다. 인간을 둘러싼 지리적 환경은 장기적으로 벼하는 구조이다. 장기지속의 구조사는 지리지와 고지도에 잘 표현되어 있다. 지리지와 고지도에 대한 문헌조사와 현지야외답사를 통하여 경관을 구체적으로 분석하고 지역성과 한국전통지역사회의 원형을 파악하고자 한다. 기존의 연구자들에 의하여 정상기의 동국지도, 김정호의 대동여지도, 북방영토인식, 군현지도, 시대상의 복원과 지리환경 인식, 회화의 측면에서 본 고지도, 지명과 영토문제, 서양식 세계지도의 전래과정등의 연구주제들에 대하여 많은 연구가 이루어졌다. 그러나 기왕의 연구는 고지도에 대한 전체적인 현황 파악과 해제, 전체적인 유형 분류, 특정주제에 대한 고지도 이용 등에 초점이 맞추어져 있었고 구체적인 지역사회에 대하여 고지도를 통시대적으로 비교 분석한 연구는 드문 편이다. 사라져가고 있는 전통경관과 자연환경의 영향을 많이 받은 촌락경관이 남아 있는 지역사회경관에 대한 고지도와 지리지를 활용한 연구가 시급하다. 고지도는 옛 지명, 산천, 도로, 역원, 행정구역, 역사적 위치의 파악과 문화경과 복원의 기초자료로서의 의미가 크므로 지역사회 단위의 연구가 필요하다. 19세기 말엽에 편찬된 읍지와 지도는 서양과 일본의 침략으로 변모되기 이전의 한국 각 지역의 모습을 추적하고 복원하는데 긴요한 역사적 자료이다. 현대 한국지역사회의 바탕을 이루고 있는 지난 400년간의 지역변화를 고지도와 지리지.읍지를 통하여 살펴봄으로써 변한 것과 변하지 않는 것을 분석하여 시대상의 복원과 지역사회의 정체성 확립에 일조하고자 한다.곡물의 여러 줄기가 합수하고 물이 역류하지 않으며 잘 감아도는 곳으로 표현할 수 있다 이러한 명당의 기본적인 원리는 장풍(藏風)과 득수득파(得水得破)이다. 장풍과 득수란 '국'(局), 즉 산줄기와 수계로 이루어진 일정한 범위 속에 만물이 생태계 속에서 살아가는 모습인 '체형(體形)'의 의미가 나타나야 한다는 것이다. 그러나 이러한 의미는 시대에 따라 달라질 수 있는 것이다.면적의 52%를 점유하여 감자 재배지의 핵심지를 이룬다. 4. 한국 감자 재배지역 중심지의 지리적 특징은, 높은 산지지역의 산록완사면에 밭작물로 재배된다는 점과 교통이 불편한 지역으로서 도시화와 산업화 지역의 그늘 지역이 대부분이다. 강원도의 감자 재배지는 감자재배에 적합한 자연환경과 화전농업의 전통, 감자 재배기술의 전파, 중앙정부와 지방정부가 지원하는 각종 연구소 분포와 영농지도, 씨감자 생산과 협동조합의 판로 개척, 도로 개설과 포장 등의 인문지리적 요인이 영농조건을 개선하고 감자 판매를 위한 시장접근을 용이하게 하여, 남한 최대의 감자 재배지역을 형성하였다. 제주도는 산지지형과 따뜻한 기온으로 2기작이 가능하고, 감자가공 공장설립과 교통발달에 따른 육지 시장과의 접근이 용이해졌기 때문에 남한에서 2번째로 큰 감자재배지역이 되었다.(요약 및 결론에서 발췌)그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.서 뚜렷한 증식억제효과를 나타내었다.min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투

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