• Title/Summary/Keyword: Erosion relief

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Geoarchaeology of the Piseo-ri Paleolithic site, Muan (무안 피서리구석기유적의 지질.고고학적 특성)

  • Lee, Heon-Jong;Chung, Chull-Hwan;Park, Sung-Tan
    • The Korean Journal of Quaternary Research
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    • v.24 no.2
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    • pp.13-21
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    • 2010
  • The Piseo-ri site in Muan provides significant data in investigation on the Paleolithic sites in the southwest coast of Korea. Stratigraphic and geological analysis indicates that the characteristic of soil wedge can vary in accordance with soil property and relief of paleo-surface. Considering that the cultural layer was deposited after the Last Glacial Maximum, co-occurrence of the late Middle to early Upper Paleolithic stone tools suggests a possibility of redeposition of different ages resulted from active erosion. The result shows that the distribution of the Paleolithic tools and the property of soil wedge could be controlled by environmental conditions such as relief of paleo-surface and climate.

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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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Properties of Channel and Evolutions of Fluvial Terraces in Odae River (오대천의 특성과 하안단구의 형성과정)

  • Lee, Gwang-Ryul
    • Journal of the Korean Geographical Society
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    • v.44 no.3
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    • pp.224-239
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    • 2009
  • This study analyzes the properties of fluvial landforms in the upper and lower reaches and investigates the evolutions of stream and fluvial terrace in the Odae river basin. The lower basin of the river that consist of sedimentary rocks resistant to weathering and erosion processes shows higher altitude, relief and slope than the upper basin that consist of granite less resistant to weathering and erosion processes. The average width of river valley at the lower reaches is one-third to the upper reaches and the average width of river channel at the lower reaches is narrower than at the upper reaches. Based on the OSL age dating, the fluvial terrace T1 formed at the temperature-rising period during the late MIS 2 and T2 formed at the middle MIS 3, interstadial period during the last glacial period. Based on the these results, the average incision rates of Odae river are calculated as 0.205m/ka and 0.269m/ka at the upper granite area and lower sedimentary rocks area, respectively.

Some Remarkable Earth Surface Processes under the Morpho-climatic regime of Mongolian Steppe Zone (기후지형학 관점에서 본 몽골 스텝지역의 지형형성작용 특색)

  • OH, Kyong-Seob;YANG, Jae-Hyuk;CHO, Heon
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.3
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    • pp.121-129
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    • 2011
  • This work is to elucidate in typological aspect main geomorphological processes in the morphogenetic system of Mongolian steppe zone. Its morphogenesis manifest interaction of intense gelifraction and active erosion either by slope run-off or by wind. Intense gelifraction owes both to cold temperature regime with great amplitude, and to moisture associated with snow fall. Erosion of material produced by gelifraction is assured by surface run-off of summer rainfall and spring eolian activities. The geomorphological landscape sculptured by such morphogenetic processes manifest low-relief smooth slopes. This feature reveals that intense gelifraction keeps abreast with removal of weathering product by surface run-off and wind.

Cauda Equina Syndrome Associated with Dural Ectasia in Chronic Anlylosing Spondylitis

  • Ha, Sang-Woo;Son, Byung-Chul
    • Journal of Korean Neurosurgical Society
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    • v.56 no.6
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    • pp.517-520
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    • 2014
  • Cauda equina syndrome (CES) associated with dural ectasia is a rare neurologic complication in patients with longstanding ankylosing spondylitis (AS). We report a 68-year-old male with a 30-year history of AS who presented a typical symptom and signs of progressive CES, urinary incontinence and neuropathic pain of the lumbosacral radiculopathy. Computed tomography (CT) and magnetic resonance imaging (MRI) findings showed the unique appearances of dural ectasia, multiple dural diverticula, erosion of posterior element of the lumbar spine, tethering of the conus medullaris and adhesion of the lumbosacral nerve roots to the posterior aspect of the dural ectasia. Considering the progressive worsening of the clinical signs, detethering of the conus medullaris through resection of the filum terminale was performed through a limited laminectomy. However, the urinary incontinence did not improve and there was a partial relief of the neuropathic leg pain only. The possible pathogenetic mechanism of CES-AS and the dural ectasia in this patient with longstanding AS are discussed with a literature review.

Detection of the morphologic change on tidal flat using intertidal DEMs

  • Lee, Yoon-Kyung;Ryu, Joo-Hyung;Eom, Jin-Ah;Kwak, Joon-Young;Won, Joong-Sun
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.247-249
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    • 2006
  • The objective of this study is to detect a inter-tidal topographic change in a decade. Waterline extraction is a one of widely used method to generate digital elevation model (DEM) of tidal flat using multi-temporal optical data. This method has been well known that it is possible to construct detailed topographic relief of tidal flat using waterlines In this study, we generated two sets of tidal flat DEM for the southern Ganghwado. The DEMs showed that the Yeongjongdo northern tidal flat is relatively high elevation with steep gradients. The Ganghwado southern tidal flat is relatively low elevation and gentle gradients. To detect the morphologic change of tidal flat during a decade, we compared between early 1990's DEM and early 2000's DEM. Erosion during a decade is dominant at the west of southern Ganghwado tidal flat, while sedimentation is dominant at the wide channel between the southern Ganghwado and Yeongjongdo tidal flats. This area has been commonly affected by high current and sedimentation energy. Although we are not able to verify the accuracy of the changes in topography and absolute volume of sediments, this result shows that DEM using waterline extraction method is an effective tool for long term topographic change estimation.

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Acupuncture Application Case Report for Symptom Relief of Oral Leukoplakia (구강 백반증의 증상 완화에 대한 침치료 적용 사례)

  • Park, Sung-gu;Jo, Eun-hee;Choi, Hangyul;Hong, Jieun;Park, Min-cheol
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.34 no.2
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    • pp.97-101
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    • 2020
  • Oral leukoplakia is the most common premalignant lesion of the oral mucosa. This case report presents the effect of acupuncture on Oral leukoplakia. The 67 years old male patient who has suffered for 2 years was treated with Right side Saam acupucture Damjeonggyeok(BL66, GB43, LI1, GB44) without other treatment. Acupuncture was performed for 15 minutes. The effect of acupuncture was evaluated as photographic change and visual analog scale(VAS) of subjective symptoms in oral cavity. After 87th acupunture treatment during 226 days, Leukoplakias were decreased at the right side of ventral tongue and the left border of the tongue and the lower lip. Furthermore, ulcer, erosion at the left border of the tongue were disappeared and VAS of Burning pain in the tongue decreased from 8 to 2. Although acupuncture is unusual treatment for Oral Leukoplakia, this case report suggested the effectiveness of using Damjeonggyeok on Oral Leukoplakia according to Saam acupuncture method.

Geomorphological Properties and Changes of Goreabul Sand Beach in Yeongdeok (영덕 고래불 모래해안의 지형 특성과 변화)

  • Bang, Hyun Ju;Lee, Gwang-Ryul
    • Journal of The Geomorphological Association of Korea
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    • v.18 no.3
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    • pp.83-92
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    • 2011
  • The properties and changes of geomorphic relief and coastal deposits were analyzed at Goreabul sand beach in Yeongdeok-gun, the largest that in east coast of Kyungsangbuk-do Province. As the result of grain size analysis, in almost season except summer, the sands mainly deposited in Goraebul sand beach because longshore current drift northward contrary to Gangwon-do east coast, and summer longshore current is weak or change direction to south ward. Sand beach mostly came form erosion owing to typoon and storm and was deposit more coarse sand in the summer, and was produced deposition actively in the fall and winter. Front side of sand dune came from deposition on sand every season by sea breeze, especially in the winter.

Tidal-Flat Sedimentation in a Semienclosed Bay with Erosional Shorelines: Hampyong Bay, West Coast of Korea (해안침식이 우세한 반폐쇄적 조간대의 퇴적작용: 한국 서해안의 함평만)

  • Chang, Jin-Ho;Kim, Yeo-Sang;Cho, Yeong-Gil
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.2
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    • pp.117-126
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    • 1999
  • Hampyong Bay is a semienclosed and macrotidal bay which opens to the eastern Yellow Sea through a narrow inlet in the southwestern coast of Korea. In order to understand the tidal-flat sedimentation in the semienclosed setting, morphology, sediments, accumulation rate and sea cliff erosion were investigated in the tidal flat of Hampyong Bay. The tidal flat of Hampyong Bay lacks intertidal drainage systems, and generally shows the concave-upward profile whose relief is designated by marked morphological features such as high-tide beaches, intertidal sand shoals and tidal creeks. Surfacial sediments of the tidal flat mainly consist of mud, sandy mud, gravelly mud, gravelly sand and muddy gravel, thus showing the textural characteristics of multimodal grain-size distribution, poorly sorting and positive skewness. The sediments generally coarsen landward due to the increase in coarse fraction content. Sedimentary structures are deeply bioturbated, but parallel lamination and lenticular bedding are locally found in the mudflat near mean low water line. Annual accumulation rates across the tidal flat (along Line SM) average -5.2 cm/yr with a range of -45.8~+4.2 cm/yr, indicating that the tidal flat is erosional. In general, erosion rates of upper and lower tidal flat are higher than those of middle tidal flat. Seasonally, the erosion rates are much higher during spring and winter when dominant wind direction corresponds to the long axis of Hampyong Bay. Sea cliffs are eroded at a rate of 1.4 m/yr. The biggest sea cliff erosion generally occurs 1~2 months later after tidal flats were extensively eroded. Such erosions of tidal Oats and sea cliffs in the semienclosed bay setting are interpreted to be due to wind waves coupled with local sea-level rise.

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Beach and Sanddune Development along the Coastline of the Chungcheong-Namdo Province (충청남도 해안에 발달한 해빈과 해안사구)

  • Kahng, Tay-Gyoon
    • Journal of the Korean earth science society
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    • v.24 no.6
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    • pp.568-577
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    • 2003
  • The purpose of this paper is to examine the geomorphic processes of beach and sanddune development in the Chungcheong-Namdo Province. The sands consist mainly of quartz and feldspar with lesser amounts of mica and other heavy minerals. With the exception of those from the granite, the sands have a very fine texture. Another characteristic of the sand grains is low degrees of roundness and grading indicating that source areas for the material were in the vicinity of the accumulating field. Over the years, the beaches have receded as a response to the decreasing amount of depositional materials. The driving force for the formation and transformation of coastal dunes in the study area is dominant winds from the center of the Siberian High. To some extent, the erosion of coastal dunes has been a global phenomenon. The degradation process occurred most actively when spring tides attacked beaches, berms, and foredunes. The relief and shape of present-day coastal dunes is determined initially by the Pleistocene strata underneath. From the fact that the strata contained traces of frozen structure, it can be inferred that sediment once experienced the process of soil formation.