• Title/Summary/Keyword: geomorphology

Search Result 187, Processing Time 0.023 seconds

The Palaeoenvironmental Changes and Macromammal Evolution during the Pleistocene in East Asia (동아시아의 제4기 자연환경의 변화와 젖먹이근동물의 제4기적 진화)

  • Sun Joo, Park
    • The Korean Journal of Quaternary Research
    • /
    • v.2 no.1
    • /
    • pp.51-85
    • /
    • 1988
  • The understanding of the faunal sequence and palaeoenvironment of East Asia since the Late Tertiary depends mainly on the knowledge of Chinese fauna and its environmental changes. The recent Chinese researches including geology, geomorphology, climats fluctuation and loess distribution of this area have provided that the rapid uplifting of Himalayas and Qinghai/Xizang Plateau since the Lower Pleistocene was a main selective factor for the process of environmental changes in this vast territory. Although different concepts of the Plio-Pleistocene boundary have been provided, its boundary can not exceed over 2 mya. Instead of the traditional zoogeographical dicthomy in China, faunal compositions of Pleistocene are divided into three faunal zones. The knowledge of macrofaunal evolution in China are useful to understand the palaeoecology of East Asia. Palaeoenvironment of Korea during the Pleistocene Period can be reconstructed by using the analogy of the current Chinese studies.

  • PDF

Characteristics of the coastal landforms in Yeonpyeong Island (연평도의 해안지형 경관 분석)

  • Seo, Jong-Cheol
    • Journal of the Korean association of regional geographers
    • /
    • v.19 no.2
    • /
    • pp.223-233
    • /
    • 2013
  • Yeonpyeong Island, an island of Ong-jin County, is a very important and meaningful area in terms of its geo-politics and natural environment. But in spite of well preserved natural environment, because of limited access and security risk, there were little researches. In this sense this study would be meaningful for inquiring into the regional geomorphology of Yeon-pyeong Island. The major findings of this study are as follows. 1) 12 sites among 20 sites was evaluated 1st grade, and this means that geomorphic value of Yeon-pyeong Island is very excellent. 2) Coastal landforms of Yeon-pyeong Island are classified three major types which are rocky coast which consist of wave-cut platform and sea cliffs, sand or shingle beaches and coastal plain in the embayment area, and tidal flat areas and small uninhabited islands. 3) Cross sectional shape of Yeon-pyeong Island is asymmetric, since coastal erosion of island concentrate on the northern and western shore. 4) Quality and value of tidal flats will be deteriorate unless the dyke construction is stopped.

  • PDF

U-city Construction Topographic features Extraction by Integration of Digital Aerial Photo and Laser Data (항공사진과 레이져 데이터의 통합에 의한 U-city 건설 지형 특성 자료 산출 연구)

  • Yeon, SangHo;Kim, Kwanghyun
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2009.05a
    • /
    • pp.485-487
    • /
    • 2009
  • The Spatial Image contents of Geomorphology 3-D environment is focused by the requirement and importance in the fields such as, national land development plan, telecommunication facility management, railway construction, general construction engineering, Ubiquitous city development, safety and disaster prevention engineering. The currently used DEM system using contour lines, which embodies geographic information based on the 2-D digital maps and facility information has limitation in implementation in reproducing the 3-D spatial city. Moreover, this method often neglects the altitude of the rail way infrastructure which has narrow width and long length. This As the results, We confirmed the solutions of varieties application for railway facilities management using 3-D spatial image contents and database design. Also, I suggested that U-city using topographical modeling about matching methods of high density elevation value using 3-D aerial photo with laser data are best approach for detail stereo modeling and simulation.

  • PDF

3-D modeling and Application Methods for Urban Areas by Convergence of Topographical Spatial Contents (지형공간 콘텐츠 융합에 의한 도시 및 지역의 3차원 모델링 및 활용기법 연구)

  • Yeon, SangHo;Lee, Youngwook
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2009.05a
    • /
    • pp.488-490
    • /
    • 2009
  • The Spatial Image contents of Geomorphology 3-D environment is focused by the requirement and importance in the fields such as, national land development plan, telecommunication facility management, railway construction, general construction engineering, Ubiquitous city development, safety and disaster prevention engineering. The currently used DEM system using contour lines, which embodies geographic information based on the 2-D digital maps and facility information has limitation in implementation in reproducing the 3-D spatial city. Moreover, this method often neglects the altitude of the rail way infrastructure which has narrow width and long length. This As the results, We confirmed the solutions of varieties application for railway facilities management using 3-D spatial image contents and database design. Also, I suggested that U-city using topographical modeling about matching methods of high density elevation value using 3-D aerial photo with laser data are best approach for detail stereo modeling and simulation. There for of this, Using of rapid spatial information generation by various images and laser data through matching methods for the make of Spatial data base management inplementation are very powerful and much application of our life and real worlds.

  • PDF

Development of Korean Geomorphological Unit Hydrograph for Mountain Basins (산악지역을 위한 한국형 지형수문단위도 개발)

  • Kim, Hong-Tae;Shin, Hyun-Suk
    • Journal of Korea Water Resources Association
    • /
    • v.42 no.1
    • /
    • pp.75-92
    • /
    • 2009
  • The development of the method for flood runoff analysis representing Korean mountain basins have been one of big concerns for Korean hydrologists for several decades. Several traditional methods dealing with unit hydrograph have been restricted to be used in Korea basins, because of its drawbacks due to its originality from other countries and the uncertainties of control parameters as well as its linearity assumption between rainfall and runoff relationship. In this paper, several geomorphological similarity relationships for Korean mountain basins was developed by using the experimental data over 40 Korean basins. Then those were applied directly to geomorphological unit hydrograph theory to meet Korean geomorphological unit hydrograph. The developed method was applied to Andong Dam basin. The results show the applicability and simplicity of the developed Korean geomorphological unit hydrograph generally for Korean mountain basins in future. It might be needed for more validations and applications of this method over Korean regions.

A Measure on the Conservation of Geological Heritages : Geological Survey and Evaluation Forms for Geologic Outcrops (지질유산 보전방안 : 지질노두 조사표와 평가표의 작성과 활용)

  • Sagong, Hee;Lee, Soo-Jae
    • The Journal of the Petrological Society of Korea
    • /
    • v.23 no.2
    • /
    • pp.145-152
    • /
    • 2014
  • Geological heritages can be defined conveniently as geological records worthy of conservation, and are represented in most cases by geological outcrops. So survey and evaluation of geologic outcrops are necessary for better conservation of geological heritages. As a measure to prevent potential destruction of geological heritages from various development projects, I propose construction of database based on survey and evaluation forms of geological outcrop, which can also be used for environmental impact assessment. The geological survey form consists of survey area, category, subcategory, location, dimension, geologic features, photo, description, and investigator. The evaluation form consists of evaluation category, detailed evaluation, comprehensive evaluation, and evaluation grade. The evaluation category is divided into academic aspect, education effect and landscape. The detailed evaluation items for academic aspects and education effect are representativeness, rarity, diversity and typicality, while those for geomorphology and landscape are peculiarity, aesthetics and naturalness. The evaluation grades are divided into five, where the first grade means a must of conservation.

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
    • /
    • v.26 no.7
    • /
    • pp.661-667
    • /
    • 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.

Bedform Morphology of the Continental Shelf Sandy Sediments Around the Korean Peninsula (한반도(韓半島) 주위(周圍) 대륙붕(大陸棚) 사질(砂質) 퇴적물(堆積物)의 표면유동구조(表面流動構造))

  • SUK, BONG-CHOOL;KAGAMI, HIDEO;TAIRA, ASAHIKO
    • 한국해양학회지
    • /
    • v.29 no.3
    • /
    • pp.239-247
    • /
    • 1994
  • Bedform morphology of the giant ripples have been studied on the continental shelf of the Yellow Sea, East China sea and Korea-Tsushima Strait on the basis of side-scan sonar image, sub-bottom profile, sedimentary facies, geomorphology evidence and hydrology. There are well developed giant ripples ranging from 100 to 500 m in wavelengths and from 2 to 10 m in wave height at nine sites in the study area, which are covered by medium to fine sand. Most of them have been formed under the present hydrologic regime where the tidal currents and local currents or turbulence flows are superimposed. In the study area, giant ripples are produced on two different environments. One is at the geomorphic narrow zone such as the Korea Strait where currents are accelerated by the topographic effects, while the other is the sandy flat plain where tidal currents and local currents are harmonized.

  • PDF

Application of Change Vector Analysis for Monitoring Geomorphological Change Using Remote Sensing Data (원격탐사 자료를 이용한 지형변화 관측을 위한 변화벡터법 적용연구)

  • Won, Joong-Sun;Yoo, Hong-Rhyong
    • Economic and Environmental Geology
    • /
    • v.28 no.4
    • /
    • pp.405-414
    • /
    • 1995
  • An algorithm for monitoring geomorphological change using remote sensing data is investigated and tested using two LANDSAT TM data sets acquired over the Kyunggi Bay on April 15 1986 and September 22 1992, respectively. The algorithm exploits change vector analysis and tasseled cap transform. Although change vector analysis is effective for change detection, efficiency is decreased as the number of variables are increased. In this algorithm, we overcome the problem by utilizing the tasseled cap transform which can reduce six bands of LANDSAT TM data into only two components called Brightness and Greenness. The test results demonstrate that the algorithm is very effective in monitoring small-scaled changes over coastal area as well as significant changes in geomorphology. The resulting change vector image, however, is more sensitive to the changes occurred by human activities than by pure geological processes mainly because of relatively short time interval between two LANDSAT TM data sets.

  • PDF

Temporal Change of Fluvial Geomorphology in the Middle Reaches of the Sumjin River, Korea (섬진강 중류 (곡성-순창) 구간의 하천지형 변화 연구)

  • 남욱현;양동윤;김주용;김진관
    • The Korean Journal of Quaternary Research
    • /
    • v.16 no.1
    • /
    • pp.17-27
    • /
    • 2002
  • Analysis of No. 199∼145 cross-sections set up by the Ministry of Construction (1978) in the middle reaches of the Sumjin River around Sunchang, Daegang, and Goksung areas have been done for delineating the changes In fluvial geomorphic features. The entire river-bed in the study area has been considerably degraded since 1978. In some cross-sections, the thalweg shillings are observed. Two aspects are responsible for the erosion-dominant environment. First, flow velocity has been increased. Human activities including wetland destruction, ex-channel destruction and artificial levee construction reduced the channel width, and fixed the channel geometry. This has resulted in increase of the water velocity. Pebble and granule∼coarse sand are prevailing on the river-bed, indicate the high speed of the currents. Second, aggregate has been intensively mined during 1980s∼1990s around the areas. Especially, in the right side of the cross-sections No. 188∼187 and the left side of the cross-section No. 155, erosion toward under the artificial levee is remarkable. This can be led to bank failure in case of heavy rainfall.

  • PDF