• Title/Summary/Keyword: Korean coastal sediments

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Textural Characters of the Sediments from Neolithic site Moonamni Coastal Zone, East Sea of Korea -Implication of the Holocene High Stand Sea Level (강원도 동해안 문암리 신석기 유적지 퇴적층의 조직 특성)

  • 박용안;김수정;최진용
    • The Korean Journal of Quaternary Research
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    • v.17 no.1
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    • pp.27-37
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    • 2003
  • The Neolithic relics containing sedimentary deposits have been found in the Moonamni coastal zone of the East Sea, Korea. The purpose of this research is to establish the late Quaternary stratigraphy of the coastal dune deposit and to elucidate its depositional environment of the Neolithic-site sediments on the basis of analytical properties of grain size population and mineralogy of the sediments. As a result, the vertical sections of the sediments from three trenches are characterized by three major stratigraphic depositional units of Unit 3, Unit 2 and Unit 1 in ascending order. Unit 3 and 2 can be further divided into tow sub-units. Unit 3 is composed of massive sands in the lower part and muddy sand in the upper part. It is considered that the Unit 3 is a typical dune deposit showing well-sorted sands. Unit 2 is characterized by the cross-bedding, and include archaeological remains such as pottery shards. This unit can be further divided into two sub-units of muddy sand in the lower part and sand in the upper part. Unit 1 occupies the top section and consists of modem dune sediment. The Neolithic cultural remains would be accumulated in the coastal dune area in relation to dynamic condition of beach system under the high stand of Holocene sea-level at about 7,800∼6,500 yr B.P. or so.

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Dinoflagellate Cyst Assemblages in the Surface Sediments from the Northwestern East China Sea

  • Cho Hyun-Jin;Matsuoka Kazumi;Lee Joon-Baek;Moon Chang-Ho
    • Fisheries and Aquatic Sciences
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    • v.4 no.3
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    • pp.120-129
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    • 2001
  • Thirty-six dinoflagellate cysts, representing 15 genera were identified in the surface sediments obtained from the northwestern East China Sea. Three cyst morphotypes found in this survey have not previously been described in the East China Sea and adjacent waters: Seleno­pemphix sp. 2, Selenopemphix sp. 3 and Trinovantedinium sp. 1. In the northwestern East China Sea, Operculodinium centrocarpum, Spiniferites bulloideus and ellipsoidal cysts of Alexandrium were commonly observed. Moreover, it was recognized that the ellipsoidal cysts of Alexandrium, whose motile cells of A tamarense and/or A catenella are responsible to paralytic shellfish poisoning, distributed not only restricted to the coastal areas but also to the offshore stations far from the Changjiang River mouth.

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On the Limitation of Turbidity Generation Unit

  • Jin, Jae-Youll;Park, Jin-Soon;Song, Won-Oh;Oh, Jae-Kyung
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2003.08a
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    • pp.363-368
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    • 2003
  • Quantification of sediment losses into the ambient waters associated with various works of coastal developments is highly required for predicting their possible detrimental impacts on the aquatic environments. Although there have been some studies especially related to dredging (e.g., Nakai, 1978; Kirby and Land, 1991; Collins, 1995; Pennekamp et al., 1996; Lorenz, 1999; Jin et al.,2003), none can be regarded as a general guidance up to date, which results from the facts that the amount of sediments released into the ambient waters is influenced by several site/case-specific conditions, and that the existing studies have been carried out using different methods. (omitted)

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On the Behavior of Suspended Sediment near a Silt Screen and the Screen Efficiency in a Microtidal Coastal Area

  • Jin, Jae-Youll;Song, Won-Oh;Park, Jin-Soon;Chae, Jang-Won;Kim, Sung-En;Jeong, Weon-Mu;Yum, Ki-Dai;Oh, Jae-Kyung
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2003.08a
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    • pp.344-352
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    • 2003
  • Sediment plumes arising from various coastal works can cause detrimental effects on the coastal ecosystem in various manners. Although the most active countermeasure against the plumes is to restrict the works to specified time periods known as environmental windows (Reine et al., 1998), silt screens have been widely used for reducing the spreading of suspended sediments (SS) generated by coastal works. (omitted)

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Analysis the depth effect of organic pollutants and heavy metals using biostimulant ball in contaminated coastal sediments (해양오염저질의 오염물질 정화를 위한 생물활성촉진제 투여 깊이 연구)

  • Song, Young-chae;Woo, Jung-Hui;Subha, Bakthavachallam
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2015.07a
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    • pp.177-178
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    • 2015
  • Sediments play a major role in determining pollution pattern in aquatic systems and reflecting the pollutant deposition. In the present study analysis the depth effect of organic pollutants and heavy metals using slow release biostimulant ball (BSB) in coastal sediment. BSB size fixed at 3cm, depth varied from 0cm to 10cm depth and 1 and 3 month interval period was carried out for the study. The organic pollutants of chemical oxygen demand, total solids and volatile solids were significantly changed at the surface sediment (0cm)in 1 month and 3 month interval time using BSB. In contrast, sediment depth increase upto 10cm the reduction percentage decrease like to control. Vertical distribution of heavy metals are not consistent from the surface layer toward the bottom layers. Heavy metals fractions were significantly changes, the exchangeable fraction was reduced and other organic and residual fractions were stabilized percentage are increased. This finding concluded BSB is effective for reduce organic pollutants, heavy metals stabilization from the contaminated sediment.

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Sediment Fluxes in Shelf Seas Modelling and Monitoring

  • Prandel, David
    • Journal of the korean society of oceanography
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    • v.37 no.3
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    • pp.144-153
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    • 2002
  • This is a review paper, assessing progress reported in a Special Issue (Prandle and Lane, 2000) of Coastal Engineering focusing on simulation of SPM in the North Sea, against issues over a diverse range of shelf seas and their coastal margins. The broad objectives of reproducing the characteristics of sediment fluxes off an open coast and relating these to tidal and wave forcing were achieved. However, accurate computation of these fluxes remains sensitive to largely empirical coefficients used in determining erosion and deposition rates. Bed roughness strongly influences both these coefficients and the associated near-bed current magnitudes (including wave impact thereon). Bed roughness can change significantly over a tidal cycle and dramatically over seasons or in the course of a major event. Accurate simulation of sediment fluxes on a day-to-day basis is constrained by dependency on the initial distribution of mobile sediments. The latter depends on rates and locations of original sources and the time history of preceding events. Remote sensing via aircraft could provide data for assimilation into such models to circumvent these constraints. The approaches described here can be readily applied to other coastal regions to indicate the likely distributions and pathways of known sediment sources. However quantitative simulations will require an associated observational programme. A subsequent stage is to understand the evolving balance between the forecasted sediment movement - the resulting morphological adjustments and thence modifications to the prevailing tidal current and wave regimes.

Numerical Modeling of Cohesive Sediment Transport at Mokpo Coastal Zone (목포해역 점착성 퇴적물의 수송에 관한 수치모의)

  • Jung T.S.;Kim T.S.;Jeong D.K.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.9 no.1
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    • pp.36-44
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    • 2006
  • Cohesive sediment transport in coastal region has been studied by numerical modeling. A finite element numerical model was setup to simulate hydrodynamics and sediment transport in the coastal region with complex topography. Only physical features of observed sediments has been used to determine erosion rates of bottom sediments together with the previous research results. The simulation results using the simply determined equation of erosion rates were compared with time variations of the observed SS concentration and showed good agreements. In conclusion, this method can be used to estimate transport of cohesive sediment conveniently.

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Modeling of Sedimentation and Vertical Dispersion of Coastal Sediment Particles Contaminated with PCBs (PCB로 오염된 연안 퇴적물 입자의 침강 및 연직확산 모델연구)

  • Lee Du Gon
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.1 no.1
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    • pp.39-46
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    • 1998
  • This study presents a numerical model that can simulate changes of particle size distribution (PSD) of PCB-contaminated coastal sediments. The developed model has one spatial dimension including sedimentation and vortical dispersion as well as coagulation. The reason for considering the vortical transport mechanisms is to calculate residence time of the particles. Using the model and Initial PSD data based on actual coastal sediments contaminated with PCBs, this study shows results of model simulations. Within 48 hours of the simulation time, the PSD changed significantly and the particles were removed from water in different rates between different particle sizes. It also shows that coagulation can act an important role in this process. The model may be useful in assessing the range of resuspended sediments that can pollute neighboring areas during environmental remediation projects such as dredging.

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Application of Response Surface Methodology for optimize the Biostimulant ball and stabilize Heavy metals pollutants in contaminated coastal sediments

  • Song, Young-chae;Subha, Bakthacachallam;Woo, Jung Hui
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2015.07a
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    • pp.179-180
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    • 2015
  • The variety of organic and inorganic pollutants are introduced to coastal sediment and making highly contaminated due to rapid development of industralization and economic development. Numerous contaminants are release into marine sediment and it significantly affect marine aquatic environment. In the present study stated the optimize the biostimulant ball (BSB) in coastal sedimentand stabilse the heavy metals present in the sediment. The effective variables like BSB size, distance and month variables on Cu stabilization was determined by using Response surface methodology(RSM). The analysis of variance (ANOVA) and coefficient determination (R2) of Cu reduction 0.9610 and maximum stabilisation was obtained in 3cm ball size and 5.5cm distance and 4 month interval time. This result revealed that the BSB in effective for Cu reduction in coastal sediment.

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