• Title/Summary/Keyword: Western coast

Search Result 530, Processing Time 0.029 seconds

Uplift Rate in the Eastern Block of the Ulsan Fault (울산단층 동부 지괴의 융기율)

  • Lee, Gwang-Ryul;Park, Chung-Sun
    • Journal of The Geomorphological Association of Korea
    • /
    • v.27 no.4
    • /
    • pp.29-39
    • /
    • 2020
  • This study estimated influences of the Ulsan Fault on tectonic movement and uplift characteristics in the Eastern Block of the Ulsan Fault. The averaged uplift rate in the Northern Coast of the Eastern Block was 0.202 m/ka, while the site in Seokbyeong-ri, Guryongpo-eup, Pohang-si, showed relatively high rate of 0.249 m/ka, attributable to influences of small fault movement, called the Gangsa Fault. Higher averaged rate of 0.270 m/ka than in the Northern Coast was calculated in the Southern Coast of the Eastern Block. The site in north of Haseo-ri, Yangnam-myeon, Gyeongju-si, showed the highest rate, suggesting influences of the Eupcheon Fault. The Western Block of the Ulsan Fault indicated the averaged rate of 0.208 m/ka, similar to that of the Northern Coast. The sites approximately 10 km apart from the Ulsan Fault showed 1.3 times higher rate in the Eastern Block than in the Western Block, while similar rates were calculated in the sites >20 km apart from the Ulsan Fault. These distributions of the rate suggest that the Ulsan Fault has significantly influenced development of marine terrace and tectonic movement in the study area, while local fault movements have also played a role.

Temporal and Spatial Variation of SST Related to the Path of Typhoons around the Korean Waters in Summer (태풍 통과에 따른 한국 연근해 수온 변동)

  • 서영상;김동순;김복기;이동인;김영섭;김일곤
    • Journal of Environmental Science International
    • /
    • v.11 no.7
    • /
    • pp.627-636
    • /
    • 2002
  • While typhoons were passing by the coastal and offshore waters around the Korean peninsula, the variations of the sea surface temperature (SST) were studied. To study on the variation, the data related to the 22 typhoons among 346 typhoons which occurred in the western Pacific during 1990∼1999, daily measured field SSTs at coastal and offshore, and imageries from advanced very high resolution radiometer on NOAA satellite during 1990∼1999 were used. The average variations of the SSTs were -0.9℃ at coastal waters and -2℃ at offshore around the Korean peninsula while the typhoons were passing by. In very near coastal waters from the land, the SST was not changed because the bottom depth of the coastal waters was shallower than the depth of thermalcline, while the typhoon was passing. The temporal and spatial variation of SSTs at coastal waters in summer were depended on the various types of the typhoons'paths which were passing through the Korean peninsula. When a typhoon passed by the western parts including the Yellow Sea of the Korean peninsula upwelling cold water occurred along the eastern coastal waters of the peninsula. The reason was estimated with the typhoon that was as very strong wind which blew from south toward north direction along the eastern shore of the peninsula, led to the Ekman transport from near the eastern coastal area toward the offshore. While cold water was occurring in the eastern coast, a typhoon passed over the coastal area, the cold water disappeared. The reason was estimated that the cold water was mixed up with the surrounding warm water by the effect of the typhoon. While a cold water was occurring in the eastern coast, a typhoon passed by the offshore of the eastern coast, there were the increasing of the SST as well as the disappearing of the cold water. While a typhoon was passing by the offshore of the eastern coast, the cold water which resulted from the strong tidal current in the western coast of the peninsula was horizontally spread from the onshore to the offshore. We think that the typhoon played the role of the very strong wind which was blowing from north toward south. Therefore, the Ekman transport occurred from the onshore toward the offshore of the western coast in the Korean peninsula.

Response Activities for Tar Ball Pollution from the 'Hebei Spirit' Oil Spill in the Southwestern Sea of Korea (서남해역에서 허베이스피리트호 원유유출 사고에 의해 생성된 타르볼 방제작업)

  • Cho, Hyun-Jin;Kim, Jeong-Yeop;Yang, Mun-Chul;Seo, Kang-Ryul;Min, Nam-Gi;Im, Sung-Huk;Jeon, Sung-Gun;Kim, Hee-Sik;Kim, Young-Hwa;Kim, Gi-Hun;Chang, Sun-Hee
    • Journal of the Korean Society for Marine Environment & Energy
    • /
    • v.12 no.4
    • /
    • pp.279-283
    • /
    • 2009
  • Approximately 12,547 kL of oil from the tanker 'Hebei Spirit' released into the western sea of Korea, which subsequently reached and covered extensive areas of the western coastlines of Korea. In the following days great numbers of tar balls hit the southwestern coast. Three different cleanup methods were used to mediate the southwestern coastline tar ball pollution by Korea Coast Guard (KCG) net setting, manual pick up, and sweeping them up. Net setting was useful in protecting coastlines from being hit by tar balls. The cold weather in winter conditions helped the tar ball response efforts because it caused them to harden, allowing them to be swept up from beaches and to be gathered up by hand.

  • PDF

Spatial Distribution and Time Variation of M2 Tide and M4 Tide in the Western Coast of Korea (서해 연안해역에서 M2 분조와 M4 분조의 분포 및 변화)

  • Jung, Tae Sung;Jeong, Jin Kwang
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.25 no.4
    • /
    • pp.255-265
    • /
    • 2013
  • In the coastal region of Korea, historical tide harmonic constants were collected. Long-term tides and short-term tides observed by the KHOA were analyzed by a tide harmonic analysis method. Based on the harmonic constants, tidal characteristics such as tide asymmetry in Korean coastal waters were investigated. The harmonic constants obtained from the long-term tide data in the western coast have been used to show the relation between tide variation and reclamation project. $M_2$ amplitudes in the western coast have been decreased and $M_2$ phases were faster. $M_4$ amplitudes also were reduced and $M_4$ phases were faster in overall. In Mokpo and Kunsan tidal nonlinearity is relatively conspicuous. Overall, non-linearity of tidal currents is higher in the tidal channels flowing fast. The tidal non-linearity has increased by the development projects including large reclamation. The flood dominant characteristic in the northern and central part of Korean western coastal waters and the ebb dominant characteristic in the southern part have been intensified. The construction of Saemangeum sea dike has significantly changed the tidal characteristic in Korean western coastal waters.

Regional Variations in Pacific Oyster, Crassostrea gigas Growth and the Number of Larvae Occurrence and Spat Settlement along the West Coast, Korea (서해 지역별 굴 Crassostrea gigas 성장 특성, 유생 출현량 및 채묘율)

  • Lim, Hyun Jeong;Back, Sang Ho;Lim, Mae Soon;Choi, Eun Hee;Kim, Su Kyoung
    • The Korean Journal of Malacology
    • /
    • v.28 no.3
    • /
    • pp.259-267
    • /
    • 2012
  • Due to the oil spill incident in December 2007, every facility of oyster culture was removed in western coast especially in Taean and Seosan. To restore oyster resources in Taean and Seosan, we brought oyster seeds from southern area and monitored their growth. In addition we monitored the culture environment throughout the year, and observed the number of oyster larvae and attached spats on collectors during summer. The factors of water environment were appropriate for oyster culture in both study area. The growth of shell height was larger in Uihang-ri, Taean than Jungwang-ri, Seosan. Spawning was more intensive in a short time in Jungwang-ri, Seosan than Uihang-ri, Taean. The number of oyster larvae and spats of collectors were much more in Jungwang-ri, Seosan than Uihang-ri, Taean. This study showed that transplantation of healthy oyster seeds from southern area can be a way of restoration of oyster resources in western coast. In addition, systematic approaches are necessary by building a better understanding of regional characteristics to restore and enlarge the oyster culture farms in western coast. In summary Uihang-ri, Taean will be appropriate for cultivation farms and Jungwang-ri, Seosan for seedling grounds to increase oyster culture productivity.

Characteristics of Nearshore Surge-Intensity (국내 연안의 해일강도 특성)

  • Kang, Ju-Whan;Kim, Yang-Seon;Cho, Hong-Yeon;Shim, Jae-Seol
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.23 no.6
    • /
    • pp.458-465
    • /
    • 2011
  • Characteristics of nearshore surge intensity were investigated by analyzing the tide data at 20 tidal stations. Statistical analysis of the surge data show that surge heights at the western coast are far greater than those at southern and eastern coasts, implying that each coast has its own classified characteristics. Surge height data greater than 30 cm were chosen and their intensities were calculated, and then, typhoon-induced surges were separated. The results show that while surge intensity at the western coast is conspicuous in winter due to the monsoon, it is conspicuous in summer due to the typhoon at other coasts. EOF analysis show that the 1st eigenvector at the western coast is prominent, which is considered to be consistent with above mentioned results.

A Study on the Climatic Characteristics of Korean Coastal Area and Marine Casualties (우리나라 연안역의 기후특성 및 해안에 관한 연구)

  • 윤종휘;이덕수;김세원
    • Journal of the Korean Institute of Navigation
    • /
    • v.18 no.1
    • /
    • pp.23-30
    • /
    • 1994
  • By use of the Climatological Report(1982~1991) and the Marine Casualty Report(1982`1992), marine casualties caused by meteorological factors and climatic characteristics along Korean coast were analysed. Marine casualty by meteorological factors can be classified into three kinds such as collision, aground and sinking. On the whole collision was mainly caused by dense fog and heavy precipitation, and aground and sinking was caused by strong wind and high sea. As results of analysis of the distribution of wind, fog and precipitation at major ports in Korea, climatic characteristics along Korean coast are as follows. in the eastern coast, wind was relatively weak and fog was not so frequently formed, while strong wind blew all the year round and fog appeared from April to August in Ulleung Island. In the southern coast, the wind was strong in both winter and summer, fog formed frequently in late spring through mid-summer and heavy precipitation was in summer. Typhoon affecting Korea was usually passing this area to the East Sea. In the western coast, strong wind was prevailing in winter at southern region and fog was formed very frequently throughout the year.

  • PDF

On the Annual Variation of Mean Sea Level along the Coast of Korea (한국연안 평균 해면의 연변화)

  • 강용균;이병돈
    • 한국해양학회지
    • /
    • v.20 no.1
    • /
    • pp.22-30
    • /
    • 1985
  • The mean sea level(MSL) along the coast of Korea is high in summer and low in winter, mainly due to the inverse barometric effect and the steric departure. The MSL associated with the inverse barometric effect is spatially uniform and has an amplitude of 8.5$\pm$0.8cm. The thermal departure, with amplitude of 4~8cm, is most dominant in the Yellow Sea. The MSL in the South Sea of Korea is strongly affected by the haline departure, which has an amplitude up to 5cm. The annual range of MSL along the western and eastern coasts of Korea are about 40 and 20cm, respectively. The spatial inhomogeneity of the annual range of MSL arises mainly due to the influence of the Asian monsoon, which amplifies (weakens) the annual MSL along the western (eastern) coast of Korea.

  • PDF

Clay Minerals and Their Distribution in the Soft Ground Deposited along the Coastline (한국 해안에 퇴적된 연약지반의 점토광물의 종류와 분포)

  • 김상규;임희대;문성권
    • Geotechnical Engineering
    • /
    • v.14 no.6
    • /
    • pp.73-80
    • /
    • 1998
  • In order to identify clay minerals in the soft ground, which has been deposited along the coastline of the Korean peninsula, 14 samples have been taken at different locations and then X-ray diffraction analysis is carried out for them. It is known from the analysis that the various kinds of clay minerals mixed with different portions exist in the soft ground, but halloysite is not traced in any samples. It is featured regionally that kaolinite and illite are found in the western coast and the southern coast. Montmorillonites exists only in the western coast. This feature of regional occurrences can be explained with the help of geology of the region. Activities determined from physical properties of the soils do not coincide with those of clay minerals identified from X-ray diffraction analysis.

  • PDF