• Journal of the Mineralogical Society of Korea
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• v.32 no.2
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• pp.103-111
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• 2019

In this study, characteristics of sediments and suspended solids flowing into Andong and Imha Dam was analyzed by color, X-ray diffraction and ICP/MS analysis. The minerals of sediments and suspended solid consist mainly of quartz, albite, chlorite, illite and small amounts of montmorillonite and kaolinite. Unlike the Andong Dam, the Imha Dam sediments contain large amounts of calcite. Color of sediments and suspended solids varies from grayish brown to dark orange. The concentrations of major heavy metals of sediments and suspended solids in the Andong and the Imha Dam are higher than the US National Oceanic and Atmospheric Administration standard values. The concentration of heavy metals in sediments of Andong is higher than that of Imha Dam because concentration of heavy metals in the suspended solid flowing into Andong is higher than that of Imha Dam.

• Journal of the korean society of oceanography
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• v.39 no.1
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• pp.26-34
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• 2004

The evolution of intricate and striking patterns of suspended sediments (SS), which are created by certain physical dynamics in the East China and Yellow Seas, has been investigated using satellite ocean color imageries and vertical profiles of particle attenuation and backscattering coefficients. The structure of these patterns can reveal a great deal about the process underlying their formation. Sea surface temperature (SST) analyzed from the Advanced Very High Resolution Radiometer (AVHRR) thermal infrared data were used to elucidate the physical factors responsible for the evolution of suspended sediment patterns in the East China Sea. The concomitant patterns of suspended sediments were tracked from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) ocean color data. The detailed examination about these patterns gave birth to the definition of the evolution of suspended sediments (SS) into four stages: (1) Youth or Infant stage, (2) Younger stage, (3) Mature stage, and (4) Old stage. We describe about the three directional forces of the tidal currents, ocean warm currents and estuarine circulations that lead to occurrence of various stages of the evolution of suspended sediments that increase turbidity at high levels through out the water column of the inner and outer shelf areas during September to April. The occurrence of these four stages could be repeatedly observed. In contrast, vertical profiles of the particle attenuation ($c_{p}$) and backscattering ($b_{bp}$) coefficients displayed obvious patterns of the propagation of suspended sediment plume from the southwestern coastal sea that leads to eventual collision with the massive sediment plume originating from the Yangtze banks of the East China Sea.

• Journal of Environmental Science International
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• v.11 no.6
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• pp.483-488
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• 2002

Suspended sediment outflows mainly by natural situation and artificial action and affects in down-stream. This research studied suspended sediments origination in forests size and mountain stream for natural situation, density for artificial action, and measured the size and possible quantity of suspended sediments origination and studied obstruction method of the generation by artificial action. As the result, I found that the size of generation is about 2~3% of forest size and the forest size which is affecting bare area of valley is about 1∼2ha. In addition, possible outflow segments quantity by artificial facilities is assumed to be maximum 200ton/ha and abstract of mountain incline for mountain development needs minimize bare area valley by make right angle with minimum size.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.4
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• pp.247-256
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• 2002

Distribution of surface and suspended sediments was studied to understand sedimentary processes of finegrained sediment near the cooling water intake of Pyongtaek power plant on the west coast of Korea. The grainsize of surface sediment during the winter was coarser in the opened northern area than sheltered southern area. During the summer, finer sediment was found in the east (landward) than west due under dominantly the influence of tidal current. The concentration of suspended sediments was higher in the winter than summer and in the mid- to deep waters than surface waters. Asymmetry of tidal current induced net landward transport of suspended sediments. Landward transport of suspended sediments was most significant at the beginning of flood time when water level is low. Net suspended sediment fluxes ranged from 3.4$\times$10$^{-3}$ kg.m$^{-2}$ .s$^{-1}$ to 5.7$\times$10$^{-3}$ kg.m$^{-2}$ .s$^{-1}$ This large landward transport of suspended sediments is attributable to combination of enhanced flow induced by intake of cooling water and artificial structures near the water intake.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.3 no.1
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• pp.38-44
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• 1991

A simple box model was applied to the sedimentation of fine-grained sediments in a rectangular basin. Using the model explanation of the net depositional process of One-grained sediments in a small tide-dominated rocky embayment was possible by a careful evaluation of coefficients for erosion and deposition. For a basin with an inlet through which the exchange of suspended sediments occurs between open sea. the model shows that the time-averaged concentration of suspended sediments for a tidal cycle reaches a steady state initial abrupt change in concentration. During a tidal cycle deposition of sediments seems to occur when the magnitude of tidal currents is substantially low near the slack waters. Resuspension and erosion of bottom sediments take place near the peak of tidal currents. For a depositional basin. Gamagyang Bay, the duration and the maximum rate of deposition appear to be longer and higher than those of erosion. which accounts for the net deposition of fine-grained sediments. The time-averaged concentration of suspended sediment in the basin is slightly lower than that of the open water due to the net deposition. The instantaneous concentration of suspended sediments showed the maximum value about an hour before high water and the minimum about an hour after low water.

• Magazine of the Korean Society of Agricultural Engineers
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• v.24 no.4
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• pp.80-91
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• 1982

To precict the suspended sediments which are 80% of total sediments in a flood disch- arge, an equation representing vertical distribution of sediment concentration was derived based upon the diffusion theory and the logalithmic velocity distribution function in the tubulent flow mechanism. The hypothesis that the uniform mass transfer is occurred at upper part along the center line of water depth, was established as a preconition to solve the problem. The theorecal and the observed values were compared. And the theoretical equation was modified to be fit the theoretical values the observed values. Observed results are as follow; 1) Equation 12) is the theoretical equation representing the vertical concentration distri- bution of suspended sedimenta 2) Rous&exonential type vertical concentration distribution equation shows signification errors near the water surface. But the equation 12) shows substation cocentration values near the water surface. 3) Equation 15) is the modified theoretical equation which is possible to predict the vertical concentration distribution of suspended sediments.

• Ocean and Polar Research
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• v.30 no.4
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• pp.519-536
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• 2008

The relatively tranquil area within the Gogunsan Archipelago was for the first time investigated preliminarily with respect to modern sedimentological processes in association with the emplacement of the Saemangeum Dyke. Basic sedimentological observations, bathymetry and surface sediments were performed twice during 2006-2008 to compare the results and elaborate changes during that period of time. In addition, sediment dynamical observations were carried out with latest measuring equipment along two transects crossing the entrances of the archipelago, including 12-hour onboard measurements of current, suspended sediments, temperature, and salinity. This dataset was used to reveal hydrodynamic characteristics for spring season April-May and to estimate the direction and relative magnitude of the net flux of suspended sediments. There occurred three depositional areas (A to C) within the archipelago, where sediment texture was also changed. In area A, around Yami Island and the dyke, and area B, in the center of the archipelago, surface sediments became coarsened over the two-year period; sand content increased 5% at the expense of silt content in the former, whereas silt content increased 3% at the expense of clay content in the latter. By comparison, area C in the western entrance of the archipelago shows a textural trend of fining with more silt and clay (combined increase of 5%) at the expense of sand content. The accumulation of sediments in areas A and B is attributable to the sand and silt resuspended from the seabed sediments off sector 4 of the dyke during the winter. The origin of the fine materials depositing on area C is uncertain at present, although suspended sediments moving offshore around the archipelago may be one of the most likely candidates for the source. The temperature of seawater increased rapidly from $9-10^{\circ}C$ in April to $14-16^{\circ}C$ in May, whereas salinity remained more or less constant at 31-32%o during the two months. Both of these parameters showed little variations with depth through a tidal cycle, suggesting good mixing of seawater without any help of significant waves. The consistency of salinity during a tidal cycle also indicates no insignificant effects of freshwater from the rivers Mangyung and Donjin emitting through the opening gap near Sinsi Island. The suspended sediment concentrations were higher at the entrance between Sunyu and Sinsi islands than at the entrance between Hoenggyong and Sinsi islands, ranging from 20 and 30 mg/l and from 5 and 15 mg/l, respectively at the sea surface. Although tidal currents were variable across a transect between Sunyu and Sinsi islands, the currents across the entrance between Hoenggyong and Sinsi islands flowed consistently in the same direction all over the transect during a tidal cycle. The estimation of net flux of suspended sediments indicates that suspended sediments are transferred to the Gogunsan Archipelago mainly through a relatively deep trough adjacent to Sinsi Island toward the shallow area around Yami Island and the dyke.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.2
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• pp.99-106
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• 2015

To estimate the effects of suspended sediments flowing into the Saemangeum Reservoir on the extent of contamination of the reservoir, the suspended sediments were collected with sediment traps, which were installed from the upstream of the Mankyung and Dongjin Rivers to estuary of the reservoir, respectively, and the sedimentation rates and the chemical characteristics of suspended sediments were analyzed. The sedimentation rates in the Mankyung and Dongjin Rivers were ranged from 0.01~5.06 and $0.01{\sim}8.75kg/m^2/day$, respectively. Those were higher to the upstream of rivers, and were mainly affected by flood events. The concentrations of organic matters were from 3.3 to 9.6 times higher than those in the stream sediments and were higher after flood season, indicating the contaminants come from the non-point sources on the basin. The concentrations of total nitrogen and total phosphorus in the suspended sediments showed the same trend with the organic matters. These results indicate that the suspended sediments from the basin of the Mankyung and Dongjin Rivers are highly contaminated and the countermeasures to manage the sources of contamination on the basin are required to maintain the water quality of the Saemangeum Reservoir.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.1
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• pp.16-24
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• 2011

EFDC model was applied to reproduce velocity fields and to evaluate the dispersion characteristics of suspended sediments (SS) around a Daesan port. Numerical results using two-dimensional hydrodynamic model of EFDC showed good agreements through comparison with the time series and harmonic analysis of the tidal elevations. The dispersion patterns of the suspended sediments using the calculated velocity fields were calculated to move from east to northeast direction in flood tide and from west to southwest in ebb tide for dredging of sea route, respectively. Also, the suspended sediments were widely dispersed into the front areas of a Daesan port, Nanji-do and Garorim bay in the long-term. Therefore, it was inferred that the environmental problems for sea pollution would be occurred seriously if the dredging for sea route would be continued in the long-term.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.3
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• pp.340-348
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• 2003

Sedimentological investigations on surface and suspended sediments were performed in Kwangyang Bay of the middle South Sea in order to reveal recent changes in depositional environments concerning anthropogenic influence. A variety of coastal developments caused the texture of the surface sediments to become distinctively finer, particularly in the southwestern part of the bay. Accordingly, the westward lining sedimentary facies was somewhat simplified from triple-mode distribution to the dual-mode one by the construction of POSCO. This east-west distribution to the sedimentary facies has recently graded into the north-south distribution by further construction of other industrial complexes including Kwangyang Port. The prominent textural changes in surface sediments are most likely associated with weakening of tidal currents related to the developments which is anticipated to be .still continued. The distribution and flux estimation of suspended sediments suggest a noticeable import of fine particles into the bay predominantly through a northern entrance rather than the southern entrance. The movements of suspended sediments in the water level near the seabed prevailed over those of the mid and surficial levels.