• The Journal of Engineering Geology
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• v.10 no.2
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• pp.133-149
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• 2000

The study area which contains the coastal terrace of the southeastern part of Korean peninsula, well developed the lineaments which are NNE, NE and WNW directions. The area crops out Cretaceous sedimentary rocks and granite porphyry, Tertiary conglomerate, tuffite and basalt and Quarternary deposits. Coastal terraces are subdivided into low, middle and upper terraces(LT, MT, UT) based on the topographic levels. Terrace gravels are deposited on these wave-cut erosional surface during the initial lowering stage of sea level fluctuation. Terrace gravels are typified by granule to pebble layers with slightly inclined beddings. These gravels are interpreted as beach gravels belonging to berm or swash zone based on the present distribution of beach gravels. The Suryum fault is characterized by the thrust which is gradationally changing the strike from ENE to NNE. The extension of the fault is about 200m and Maximum displacement is about 1.5m.

• Proceedings of the KSEEG Conference
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• 2005.04a
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• pp.111-113
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• 2005

• 한국해양학회지
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• v.18 no.2
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• pp.149-160
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• 1983

Extensive wind, sea level and sea surface temperature (SST) data collected along the east coast of Korea in 1973-1979 were used to ascribe the variations of sea level and SST associated with wind forcing during summer. Alongshore components of wind were dominant but the offshore components were little significance in the southeast coast in summer. The variations in SST and sea level adjusted barometricallyagreed with the upwelling-downwelling processes and showed a rapid response to wind.Appearance of cold water to the surface in the upwelling region concurred well with te periods of positive y-component wind when the tangential line at Ulgi was takem as the y-axis. In general, SST at Ulgi and Gampo as well as the adjusted sea level at Pohang, Ulsan and Busan decreased significantly when strong winds favorable for upwelling persisted for more then three days whereas they increased during the relaxation or unfavorable periods. The period of an upwelling event, on the average, was about 10 days and the mean speed of alongshore sind was 4.0m/sec.

• Journal of the Korean Geographical Society
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• v.35 no.1
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• pp.17-38
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• 2000

The marine terraces often offer come important clues to understand the topographic development during the Quaternary and the present landforms in korea. We examined the mechanism of the marine terraces formation along the coast from Samjung-Ri(community), Guryongpo-Eup(county) to Haseo-Ri, Yangnam-Myun(county), Gyungju-Si(city). Among the various but unique factors of the given coastal environment, which should contribute to the marine terraces formation together, we focused on five possible factors for the present stydy. Geologic difference in bedrocks, protrusion degree of coastiline, topological relief of sea-bottom, fluvial characteristics on land, and pattern of the waves appeared to act cooperatibely on the terrace formation of Southeastem coast in korea, while the fluvial characteristics seemed play a significant but localized role in it. Wide distribution of middle surfaces on the coast of Samjungri-Janggilri could be due to the concentration of the high waves and the weakness of the Tertiary volcanic rocks. For the sporadic distribution of the terraces on the coast of Gupungri-Gyewonri, it seemed attributable to the erosion -susceptible weak bedrock, the coastline of inner bay, shallow sea-bottom with the gentle relief, and other fluvial characteristics with the low divides. Together with the geologic difference in bedrock, other factors including protrusion degree of coast, topological relief of sea-bottom, and the transportation loads by the stream Daejongchon are believed to act cooperatively on the mechanism of the marine terraces formation on the coast of Duwonri-Upchonri.

• 한국해양학회지
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• v.22 no.2
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• pp.71-79
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• 1987

We studied the annual variation of water temperatures in the upper 200m off southeast coast of Korea by means of harmonic analysis of the temperatures at 10 standard depths of 51 stations. The distributions of the mean temperature in coastal zone are almost parallel to the coast, whereas those in offshore are almost zonal. With an increase of depth, the annual amplitude decreases nearly exponentially and the annual phase increases nearly linearly. The average e-folding depth for the annual amplitudes is 65m, vertical change of the annual phase is 180 per 200m, and the vertical eddy conductivity is $4\textrm{cm}^2/sec$. Annual variations of temperatures in the coastal zone of a few tens miles from the coast are considerably different from those in offshore area. The e-folding depths in coastal zone are shallower than those in offshore region, and the changes of phase with depths in coastal zone are smaller than those in offshore region.

• Journal of the Korean Geographical Society
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• v.36 no.4
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• pp.458-473
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• 2001

The classified map of geomorphic surfaces is the most basic data for the geomorphological research. Up to recent days, the traditional methods extracting specific geomorphic surfaces are accomplished by analyzing the aerial photographs and topographical maps, and field works. Also it needs a lot of time and expertness. Furthermore it is difficult to gain the aerial photographs in Korea. Since digital maps in Korean Peninsula are almost completed recently, we tried to extract specific surfaces by analyzing the characteristics of marine terraces based on the level of paleoshoreline and slope analysis on the terrace surface using GIS. However, research used GIS was hardly found up to date, therefore many problems are not be solved yet. The aim of this study is to develop the more efficient and objective method for the extraction and classification of specific geomorphic surfaces by using GIS in Gampo-eup, Gyeongju city, Southeastem Coast in Korea, where a lot of traditional research has already accomplished. For this aim, we have designed the process of extracting specific geomorphic surfaces, chosen the factors that was Gyeongiu city, Southeastem Coast in Korea, where a lot of traditional research has already accomplished. For this aim, we have designed the process of extracting specific geomorphic surfaces, chosen the factors that was suitable for classification of specific geomorphic surface, and presented method of setting up optimum criteria of extraction. As last, effectiveness and problems of these methods were investigated through conincidence rate and error rate.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.6
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• pp.298-307
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• 2021

Typhoons occur intensively between July and October, and the sea level is the highest during this time. In particular, the mean sea level in summer in Korea is higher than the annual mean sea level about 14.5cm in the west coast, 9.0 to 14.5cm in the south coast, and about 9.0 cm in the east coast. When the rising the sea level and a large typhoon overlap in summer, it can cause surges and flooding in low-lying coastal areas. Therefore, accurate calculation of the surge height is essential when designing coastal structures and assessing stability in order to reduce coastal hazards on the lowlands. In this study, the typhoon surge heights considering the summer mean sea level rise (SH_m) was calculated, and the validity of the analysis of abnormal phenomena was reviewed by comparing it with the existing surge height considering the annual mean sea level (SH_a). As a result of the re-analyzed study of typhoon surge heights for BOLAVEN (SANBA), which influenced in August and September during the summer sea level rise periods, yielded the differences of surge heights (cm) between SH_a and SH_m 7.8~24.5 (23.6~34.5) for the directly affected zone of south-west (south-east) coasts, while for the indirect southeast (south-west) coasts showed -1.0~0.0 (8.3~12.2), respectively. Whilst the differences between SH_a and SH_m of typhoons CHABA (KONG-REY) occurred in October showed remarkably lessened values as 5.2~ 14.2 (19.8~21.6) for the directly affected south-east coasts and 3.2~6.3 (-3.2~3.7) for the indirectly influenced west coast, respectively. The results show the SH_a does not take into account the increased summer mean sea level, so it is evaluated that it is overestimated compared to the surge height that occurs during an actual typhoon. Therefore, it is judged that it is necessary to re-discuss the feasibility of the surge height standard design based on the existing annual mean sea level, along with the accurate establishment of the concept of surge height.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.82-89
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• 1999

미국의 전파항법정책(FRP Federal Radionavigation Plan)은 여전히 SA정책(미국방성에서 GPS 위성 궤도에 오차를 실어 전파발사를 하는 정책)을 유지하고 있고, P(Y)코드 접속에 의한 고정밀 위치정보 사용 역시 미군 및 NATO군 등 미 국방성에서 인가한 사용자에게만 허용되고 있는 관계로 그 외의 사용자는 3차원 고정밀 위치정보가 요구되는 항공기 이착륙 유도시스템, 해ㆍ육상 정밀 구조/탐색 및 육ㆍ해ㆍ공 특수목적 등에 군사용 P(Y)코드대신 DGPS를 사용하고 있다. 본 연구는 한반도 남해안 및 동해안 일부까지를 유효거리로 하고 있는 일본 Marine Radiobeaeon/DGPS 시스템에 대한 한반도 연근해에서의 위치정보 사용 가능성을 확인하기 위해 한반도 남해안에서 측정 가능한 일본 DGPS국을 선택 모델로 하여 DGPS Data 측정실험 및 위치정보 정밀도 분석을 하였다. 연구결과 군사용 P(Y) 코드수준의 정밀도를 유지하고 있어 곧 구축 예정인 한국형 DGPS 국가망과 함께 선택적으로 사용할 수 있음을 확인하였다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.5
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• pp.579-589
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• 2018

Data from the two bottom moorings of ADCP (acoustic doppler current profiler), coastal weather station and CTC (conductivity temperature depth) observations for 2001 were analyzed to describe the physical processes associated with upwelling off the southeast coast of Korea. Winds were favorable for upwelling during summer, but were not correlated with currents. Shoaling of isotherms toward the coast due to the baroclinic tilting of the strong East Korean Warm Current (EKWC) provided a favorable background for immediate upwelling-response of surface temperature to southerly winds. This baroclinic effect was supported by a significant inverse coherence between the upper-layer current and bottom temperature near the coast. This upwelling is similar to the Guinea Current upwelling, which is driven by remote forcing (Houghton, 1989). Persistent southward flow was observed below approximately $10^{\circ}C$ isotherm throughout the observation period.

• Proceedings of the Korean Quaternary Association Conference
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• 2005.10a
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• pp.48-54
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• 2005

Terrace morphology is so conspicuous in the south eastern coastal areas. Coastal terraces can be divided into 5 main surfaces, including beach and coastal alluvial plain(AP, $4{\sim}5m$), Low Terrace(LT, 8 $^{\sim}$ 25m), Middle Terrace(MT, 36 $^{\sim}$ 55m), High Terrace(HT, 63 $^{\sim}$ 86m) and upper High Terrace(uHT, above 90m). Among them Lower Terrace Formation is distributed between 8m and 20m in altitude. Both Tephra deposited of LT2 formation and OSL datings of sand layers in LT 2 and LT 3 Formations support the age of the LT 2 formation is MIS 5d or 5e, most probably 5e. The age of LT 3 is interpreted MIS 5a, based on tephra production in organic mud layers and OSL dating of sand deposits just above the beach pebbles of the LT 3. Particularly the transgression, possibly equivalent to the well-known Monastirrian episode in the Mediterranean Sea.