• Journal of Ocean Engineering and Technology
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• v.21 no.3 s.76
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• pp.8-15
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• 2007

This study is intended to examine the relationship between the magnitude of sand spit in the estuary of the stream and improvement of the quality of water that flaws into the sea, by means of hydraulic experimentation. In order to determine the effect of improvements of water quality when river flow is stagnant, the estuary flows into the sea through the small sand spit, and a two-dimensional physical model experiment was carried out. Distribution of concentration was decreased in response to an increase in length of sand spit and time. The experimental results are compared with theoretical results, based on the solution of the equation. Also, there are functions of influx prevention of salt wedge and purification of pollution water due to sand spit in small estuary.

• Water for future
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• v.8 no.2
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• pp.65-74
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• 1975

The east coast seems to have remarkably different features from the west and south coast in the geographical, geomorphological, and oceanographical senses. In this paper the auther wishes to introduce some results of investigation morphological characteristics of the river mouth in the east coast an of analysis of it's causes. There are various closing form in river mouth by many causes, but the east coast hs the same closing form(the ratio of closing; roughly 0.18), as well known, by the sand spit, and has not hydrological but littoral drift background. The river of the east coast is proved mature age from hypsometric analysis. The wave and longshore current must be principal factor to be considered, in the analysis of the closing phenomenon owing to littoral drift. The research of the blown sand is considered valuable for the next study of this subject.

• Journal of Environmental Science International
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• v.12 no.2
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• pp.151-155
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• 2003

The resources conservation system is comprehended, making Taean-haean National Park a research material by applying the fact of landowning, designating an LOP and Korea and Japan's Natural Park Act. Following conclusions were obtained in this study; Most of land areas of the National Park are privately owned; Only a few have been designated as Natural Reservation, a core reserved area on LOP, and a sandy beach, a sand dune, a sand spit, a tidal flat, a wetland, etc are distributed in the natural environment area so they were exposed to development; As seen in most of coastal type of National Parks, 13 commercial beaches are established. The annual rush to the beaches appears in July and August; Sand dune areas that have to be managed in terms of conservation, are turned into beaches. Moreover, the collective facilities areas are randomly developed. So they fail to function originally; The current Natural Park Act has no systematic devices for conservation of the natural resources on the seashore or offshore.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.26-36
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• 2003

Collected and analyzed the coastal processes at the estuary of Nak-Dong river and its near coastal area from the history of field measurements. Introduced a numerical model to predict three dimensional topographical change which are evaluated from the nearshore wave and the wave induced current fields for the objective area, and later it were related to the development of beach and shoals. With the comparison between measured and calculated, we found that the changes on the coastline and sand spit and bar development are induced not only by artificial forces due to the construction of river dike, but also by the strong impact of wave induced current. In future days, it is expected that coastline change and sand bar development at the lee side of Jinwoo-Deung and at the front of Dadae beach.

• Journal of the Korean Geographical Society
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• v.46 no.6
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• pp.693-706
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• 2011

The Geomorphological properties and ages of river-mouth bar at Song-cheon River in the East Coast of Korea, Yeongdeok-gun, Gyeongbuk Province are estimated, and the long-term and short-term changing processes and causes are analyzed. Sand grains of the bar near the coastline show the finer trends from south to north and these can be attributed to the northward movement of waves and long-shore currents. The absolute ages of bar and nearby coastal sand dune are less than approximately 100 years ago, indicating that the bar has experienced the active geomorphological changes. While the inlet located at south part of the bar between 1971 and 1995, the inlet has located at north or middle part since 1995. These may caused by the changes of movement directions of waves and long-shore currents due to the apparent northward movements of winds and currents. In short-term, the higher elevation, larger area, simpler landform relief and more variable location of inlet and morphology of bar can be observed between September and March due to the dominance of sedimentary processes by wave and wind processes.

• 한국해양학회지
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• v.11 no.2
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• pp.64-70
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• 1976

Forty four dredged surface sediments from the bottom of the Hwajinpo Lake and its vicinity were investigated in terms of the sedimentary depositional environment. The characteristics of the sedimentary textures, chemistry and clay mineralogy of these sediments were analysed by X-ray diffraction, chemical (EDTA titration and atomic absorption), sieving and pipette techniques. The lake sediments were chiefly mud and the beach sediments were sand. However, the lake sediments from its seaward zone were sand or muddy sand. The textural parameters that is, mean size, sorting value and their pair diagram seems to be characteristic in the area studied. Based on these data it seems to be reasonable thatthe Hwajinpo Lake was developed by the accretion and growth of a barrier spit along the shore investigated. The chief clay minerals identified were kaolinite, muscovite and the presence of vermiculite was believed as minor composition. The major chemical compositions of these sediments, that is, SiO$\sub$2/, Al$\sub$2/O$\sub$3/, Fe$\sub$2/O$\sub$3/, CaO, Na$\sub$2/O and K$\sub$2/O were contained in unit sample. The ratio of alumina to sodium oxide as a chemical index seems to indicate that the inner lake sediments are more mature than the outer one.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.2
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• pp.96-102
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• 2014

A three-dimensional beach evolution model was presented to predict morphodynamics around a river mouth. The presented model was based on the depth-averaged (2DH) and quasi three-dimensional (Q-3D) nearshore current modules, and the model took into account shoreline changes, the effect of advection diffusion of suspended load and discharged sediments from the river. First, the 3D beach evolution model was applied to the formation of sand spits and terrace at the river mouth in order to investigate the performance of the model. Secondly, the model was applied to the river mouth at the Ara River, facing the Sea of Japan. The formation of sand spit at the Ara River in winter season was reproduced. The computed result showed qualitatively agreement with field site observation.

• Journal of the Korean Geographical Society
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• v.41 no.3 s.114
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• pp.331-345
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• 2006

This study deals with geomorphological process of the sand dune landform including the distribution and surface environments, characteristics of sediments, origins and moving processes in lower reach and mouth delta of Duman River, Northeast Korea and China. The methodology of the study includes image analysis of Landsat TM(1992.10) and ETM(2000.9) and Spot(2005.4) for analysis of land cover, 2 times field survey for recognition of landform and acquisition of sediments raw data materials, and grain analysis and exoscopy about raw data materials. The geomorphic elements from satellite image analysis are composed of the delta, sand spit, active and stable dune, sand bar and riparian vegetated zone. Results of the grain analysis indicate the sediments originated from marine coastal zone than riverine one. This means that present sand dune not so much reflect present climatic and geomorphic environments. Result of the exoscopy analysis show that ratio of quartz, which is comparatively resistant to environment, is highest as $65{\sim}83%$ out of sediments. But the surface of the $30{\sim}40%$ of mineral grains was coated by yellow-colored stained materials, due to chemical weathering. Some grains show rough skin, looking as acicular, network structure and etching pits, affected by physical and chemical weathering.

• Journal of The Geomorphological Association of Korea
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• v.19 no.2
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• pp.123-132
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• 2012

In this study, we analyzed sedimentation and erosion environment around Halmiseom on Anmyeon Island using wind direction and wind speed data, gain size analysis data and datum-point measured values. To observe changes in sedimentation and erosion environment around Halmiseon, we installed datum points at 12 locations around Halmiseom and carried out at total of 32 field measurements from May 16th, 2010 to May 8th, 2012. The field measurement results showed that H-3, H-4, H-5 and H-9 points are dominated by sedimentation environment, and H-7, H-8, H-10, H-11 and H-12 points are dominated by erosion environment. Meanwhile, sedimentation and erosion appeared alternately at H-2 and H-6 points. These results indicate that a bank installed in the southwest side of Halmiseom prevented sand of the beach from moving to the northeast side, leaving the sand of the beach being deposited at the sites, and the northeast side, where sand was not provided from beach ridge of Halmiseon was dominated by sedimentation. That is, the southwest side of Halmiseom was dominated by sedimentation, but the northeast side was dominated by erosion in general. However, the opposite trends were observed at H-9 point of the northeast side and H-12 point of the southwest side. According to analysis, since H-9 point is located at the end of sand spit connected to Halmiseom, the supply of sediments by a tidal current is possible. On the other hand, it was difficult to analyze the cause of erosion in case of H-12 point located at the sand dune due to the short measurement period.

• Journal of The Geomorphological Association of Korea
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• v.18 no.2
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• pp.39-51
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• 2011

In this study, the shape of the Baramarae beach, Anmyeondo Area in West Coast of Korea and the changes in the sedimentation and erosion environment were analyzed in time series. As a result of the time series analysis of the shape of the Baramarae beach using aerial photographs from 1967 to 2009, the sand spit that developed in the southern part of Halmi Island was found to have had an EEN direction, but it was changed to a NNS direction, as reflected in the 2009 aerial photographs, as it gradually shifted to the west. In the onsite measurement, the H-3, H-4, H-5, and H-6 spots showed a superior sedimentation environment and the H-7, H-8, and H-9 spots showed a superior erosion environment. It was thus found that sedimentation is superior in the southwest beach and that erosion is superior in the northeast beach. The results in the spots between H-3 and H-6 indicate that the sand in the beach could not move to the northeast beach of Halmi Island due to the bank that had been established in the southwest beach of the island. On the other hand, it seems that superior erosion takes place in spots H-7 to H-9 in the northeast beach, where sand is not provided from the southwest beach of Halmi Island. It was found from the seasonal analysis that the season when superior sedimentation takes place in all the spots is autumn, and that the season when superior erosion takes place is summer. Superior sedimentation takes place in winter and spring in the southeast side and in summer in the northwest side.