• Journal of the Korean earth science society
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• v.24 no.4
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• pp.337-345
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• 2003

Surficial sediments from the northern coastal area of Jeju Island, southeastern Yellow Sea (South Sea of Korea) were analyzed for grain-size texture, some geochemical characteristics and clay mineralogy in order to assess their provenance. Rare-earth element compositions and some geochemical discrimination diagrams, especially of Ti/Al, Nb/Al and Rb/Al ratios, were revealed to be useful indices for identifying the origin of sediments. These indices, together with clay mineral compositions, suggest that the coarse-grained sediments originate from the volcanic rocks of Jeju Island, whereas the fine-grained sediments are derived from Chinese rivers, especially the Changjiang River. The oceanic circulation pattern and the physical-chemical properties of seawater in the Yellow and East China seal support the possibility that the fine-pained Changjiang (Yangtze River) sediments can reach the coastal area of Jeju Island (southeastern Yellow Sea).

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.129-130
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• 2000

황해의 남동부에 위치한 한국 남서 연안해역은 남해와 인접한 해역으로 황해저층냉수, 황해난류수, 연안수, 양자강 희석수가 영향을 미치고 있으며, 이들 수계간에 형성되는 수온전선역은 좋은 어장을 형성한다. 또한 이 해역은 주요 수산자원의 어장 및 회유환경 그리고 해조류양식 등과 관련하여 해양학적ㆍ수산학적으로 매우 중요한 해역이다. 조석전선이 해양의 1차 생산자인 식물플랑크톤의 분포 및 성장에 큰 영향을 주는 것으로 밝혀지고 있다(Bowman and Esaias, 1977). (중략)

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.1
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• pp.20-35
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• 2002

We studied the fishing ground of a yellowtail and oceanographic conditions around Chujado and Marado around Jeju Island from autumn to winter. Also we investigate the forming mechanism of fishing ground around Marado, which shows the best catch of yellowtail near Jeju island. The obtained results are summarized as follow ; 1. When the high temperature water about 15.0∼19.0 in depth of 50m distributed around Chujado and Marado, the fishing ground of Yellowtail is shows a good catch. On the contrary, when the low temperature water about 11.0∼14.0 is shows a poor catch. 2. Fishing grounds of yellowtail by handline fishing are formed with a school of Yellowtail migrating southward from the coastal sea of Korea and slaying around Marado to winter and spawn due to following factors. Firstly, a front of temperature and salinity is formed between inshore water and oceanic water around Marado. Secondly, small-size eddies and excellent horizontal and vortical mix which is created by strong tide and geographical features including irregular underwater ground and an isolated island. An abundant school of yellow tails stays in front of the tide where a good fishing ground was made.

• Journal of the Mineralogical Society of Korea
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• v.22 no.1
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• pp.49-61
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• 2009

We studied the mineral composition and mineral distribution pattern of 131 surface sediments collected at the cruise in 2000 and 2007 from Southeastern Yellow Sea, South Sea of Korea and Southern part of Jeju Island. Mineral compositions of surface sediments were determined using the quantitative X-ray diffraction analysis. Surface sediments were composed of rock forming minerals (quartz 37.4%, plagioclase 11.7%, alkali feldspar 5.5%, hornblende 3.1%), clay minerals (illite 19.2%, chlorite 4.7%, kaolinite 1.8%) and carbonate minerals (calcite 10.7%, aragonite 3.4%). Distribution of clay minerals is very similar with fine-grained sediments, and especially same as the distribution of HSMD (Hucksan Mudbelt Deposit), SSKMD (South Sea of Korea Mudbelt Deposit) and JJMD (Jeju Mudbelt Deposit). The coarse sediment seemed to be relic sediment during the last glacial maximum and mainly consisted of rock forming minerals. Whereas the fine sediments mainly composed of clay minerals. Based on the clay mineral composition, main ocean current and geographical factor, HSMD and SSKMD might have derived from the rivers around the Korean Peninsula. However, JJMD is complex mudbelt deposit, which formed by Korean rivers and oceanic sediments.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.2
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• pp.100-110
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• 2005

We carried oui a study on the marine environment and distribution of phytoplankton community, such as chlorophyll a, species composition, dominant species and standing crops in the Northern East China Sea during early summer of 2004. According to the analysis of a T-S diagram, three characteristics of water masses were identified. We classified them into the coastal water mass, the cold water mass and the oceanic water mass. The first was characterized by the low temperature and the low salinity originated from China territory, the secondary was characterized by the low temperature, the low salinity and the high density originated from bottom cold water of Yellow Sea, and the third was done by the high temperature and salinity originated from Tsushima warm current. The internal discontinuous layer among them was farmed at the intermediate depth (about $5{\sim}30m$ layer). And the thermal front by upwelling region between the cold water mass and Tsushima warm current appeared in the central parts of the South Sea of Korea. The Phytoplankton community in the surface and stratified layers was a total of 44 species belonging to 26 genera. Dominant species were Prorocentrum triestinum, Scrippsiella trochoidea, Skeletonema costatum & Leptocylindrus mediterraneus. Standing crops of phytoplankton in the surface layer fluctuated between $0.3{\times}10^3$ cells/L and $10.8{\times}10^3$ cells/L. Diatoms appeared mainly in the Tsushima warm current regions, and flagellates occurred in the frontal zone and the low salinity regions where was the transfer areas of Chinese continental coastal waters. Chlorophyll a concentration by controlled phytoflagellate ratio in the South Sea of Korea was high values in the frontal zone and sub-surface layer. It was high concentration in the upwelling and coastal waters regions, but low concentration in the Tsushima warm current regions. The Chl-a maximum layers appeared in the thermochline depth or sub-surface layer lower than thermocline. The phytoplankton production in the South Sea of Korea was controlled by the expanded coastal waters of Chinese Continent which include a high concentrations of nutrients.

• 한국해양학회지
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• v.29 no.4
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• pp.325-337
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• 1994

The distributions of heat and momentum fluxes on the surface over the oceans around the Korean Peninsula are obtained based on the surface-layer flux model of Kim and Kang (1994), and their seasonal variations are examined in the present study. the input data of the model is the oceanatmosphere data with a grid interval of 2$^{\circ}$ in longitude and latitude. The atmosphere data, which are the pressure, temperature, and specific humidity on the 1000 mb level for 3 year period of 1985∼1987, are obtained from the European center for Medium Range Forecast. The sea surface temperature (SST) is obtained from National Meteorological Center (NMC). The solar insolation and longwave radiation on the ocean surface are obtained, respectively, from the NASA satellite data and based on an emprical formula. It is shown from the net heat flux that the oceans near Korea lose heat to the atmosphere in January and October with the rates of 200∼ 400 Wm/SUP -2/ and 100 Wm/SUP -2/, respectively. But the oceans are heated by the atmosphere in April and July with about the same rate of 100 Wm/SUP -2/. The annualmean net heat flux is negative over the entire domain except the northern part of the Yellow Sea. The largest annual-mean cooling rate of about 120 Wm/SUP -2/ is appeared off the southwest of Japan. In the East Sea, the annual-mean cooling rate is 60∼90 Wm/SUP -2/ in the southern and northern parts and about 30 Wm/SUP -2/ in the middle part. The magnitude of wind stress in january is 3∼ 5 times bigger than those of the other months. As a result, the spatial pattern of annual-mean wind stress is similar to that of January. It is also shown that the annual-mean wind stress curl is negative. in the East China Sea and the South Sea,but it is positive in the northern part of the Yellow Sea.In the East sea,the stress curl is positive in the southeast and northern parts and negative in the northwestern part.