• The Korean Journal of Quaternary Research
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• v.12 no.1
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• pp.63-76
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• 1998

한반도는 산악지형이 우세하기 때문에 늪지나 호수의 발달이 불량하다. 현재 소규모 의 자연늪지는 낙동가 하류지역에 분포하며 동해안을 따라 일부 해안지역에 발달하여 있을 뿐이다. 고산지역에도 소규모의 늪지가 최근에 발견되었는데 그중에서도 무제치늪이 국내의 가장 남동쪽에 위치하고 있다. 정족산 정상부를 향하여 4개의 늪지가 차례대로 발달하여있 는데 이들의 성인은 온도차이에 의한 기계적풍화와 암석 차이에 의한 화학적 풍화적작용의 결과로 해석된다, 이들의 형성시기는 제 2늪의 습원퇴적이 가장 오래되 지층으로서 100~ 105cm 심도에서 탄소동위원소 연대측정으로 5,960$\pm$110yr BP. 의결과를 보이고 있드며 제 1늪의 습원 퇴적은 지표로부터 64~69cm 심도의 토탄층 최하부 부분에서 1,785$\pm$120yr BP. 의 연대측정 결과를 확인하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.528-530
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• 2007

IODP Expedition 311에서 채취한 퇴적물 시료들의 TOC 함량은 대부분 1 %미만이고 육지에서 해안으로 갈수록 높은 함량을 보여준다. TOC/TN비는 4에서 10의 범위를 가지고 있으며, 이 값은 대부분의 유기물들이 육성식물 보다는 조류기원임을 보여준다. 반면에 Rock-Eval 분석 열분석결과는 유기물들이 Type III 의 육성식물 기원임을 지시하고, 대부분의 유기물들이 미성숙단계 (immature stage)에 있음을 보여준다. 유기물 기원에 대한 지화학적 지시자들 사이의 불일치를 해결하기위해 유기물의 탄소동위원소 ($^{13}C_{org}$) 분석을 실시하였다. 분석된 유기물 탄소동위원소 값은 -28.4 $%_o$,에서 -23.0 $%_o$의 범위를 가지고 있으며, 이는 유기물들이 식물성 기원보다는 해수 및 담수의 조류가 혼합된 기원이 우세하다는 j것을 지시해준다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.34-35
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• 2018

낙동강 하류역은 최근의 퇴적우세 지형변화와 더불어, 기후변화에 따른 태풍강도 강화 등으로 인한 해일고 증가가 우려된다. 따라서, 과거 태풍자료를 수집 분석한 후 연구지역에 가장 큰 영향을 미친 태풍을 모델 태풍으로 선정하여 낙동강 하류역에 위치한 주요지점별 폭풍해일고 변화를 파악하였다. 실험결과, 최대 폭풍해일고는 태풍 매미 내습시에 나타났으며, 하단 매립지 전면에서 1.1~1.5m, 명지주거단지 전면에서 1.2~1.3m, 녹산국가산업단지 전면에서 1.3~1.5m로 하단 매립지 전면이 가장 크게 나타났다. 향후, 과거 지형변화를 고려한 폭풍해일고 검토를 통하여 최근의 급격한 지형변화로 인한 영향을 파악한 대비를 해야 할 것으로 사료된다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.38-39
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• 2018

낙동강 하구 하류역의 지형변화는 장기간에 걸쳐 변화가 발생하고, 이러한 지형변화의 메커니즘을 파악하는 것은 하구의 관리방안과 처리방법 등을 연구하는데 있어서 매우 중요하다. 본 연구에서는 낙동강 하구 하류역의 지형변동에 관한 기초자료를 수집 분석하였으며, 이를 근거하여 지형변화 예측실험을 수행하였다. 실험결과, 하굿둑 건설과 부산신항 건설 등의 대규모 개발사업으로 인한 해수면 축소로 인한 유속감소로 인하여 전반적인 퇴적우세 현상이 지속되는 것으로 나타났다. 또한, 해빈류 실험결과 울타리선 남쪽과 동서쪽으로 지형 발달 및 성장이 지속될 것이라 판단된다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.149-157
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• 1998

Seasonal changes of topography, sediment grain size and accumulation rate in the Gomso-Bay tidal flat, west coast of Korea, have been studied in order to understand the seasonal accumulation pattern and preservation potential of the tidal-flat sediments. Seasonal levelings across the tidal flat show that the landward movement of both intertidal sand shoals and cheniers accelerates during the winter and typhoon periods, but it almost stops in summer when mud deposition is instead predominant at the middle and upper tidal flats. Seasonal variations of mean grain size were largest on the upper part of middle tidal flat where summer mud layers were eroded during the winter and typhoon periods. Measurements of accumulation depths from sea floor to basal plate reveal that accumulation rates were seasonally controlled according to the elevation of tidal-flat surface. The upper tidal flat where the accumulation rate of summer was generally higher than that of winter was characterized by a continuous deposition throughout the entire year, whereas in the middle tidal flat, sediment accumulations were concentrated in winter relative to summer and were intermittently eroded by typhoons. The lower tidal flat were deposited mostly in winter and eroded during summer typhoons. Can cores taken across the tidal flat reveal that sand-mud interlayers resulting from such seasonal changes of energy regime are preserved only in the upper part of the deposits and generally replaced by storm layers downcore. Based on above results, it is suggested that the storm deposits by winter storms and typhoons would consist of the major part of the Gomso-Bay sediments.

• Journal of the Korean earth science society
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• v.22 no.4
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• pp.301-316
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• 2001

To consider the vertical variations of sedimentary environments and geochemical characters in the core sediments in Naju-Yeongam area od the lower part of Yeongsan River, grain-size and metal components of the sediments were analyzed. The sediments are pebble to mud and show fining upward. The core sediments are poorly to very poorly sorted and positively skewed. On the basis of grain size distributions, the sediments of the study areas were thought to have been deposited in a meandering stream. The metallic contents of sediments were presumably controlled by carbonate contents of sediments and weakly controlled by fining upward grain size distribution pattern. Enrichment factors indicating metal concentration in the sediments did not suggest any meaningful concentrations for metallic elements.

• Journal of the Korean earth science society
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• v.23 no.8
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• pp.722-735
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• 2002

In order to reveal sedimentary facies and geochemical characteristics on sediments distributed in upper intertidal zone, the southwestern coast of Korea, grain size and metal content analyses to the sediments were carried out. The grain size distribution of sediments shows very wide range from gravel to mud. The sediments are very well sorted to very poorly sorted and mostly positively skewed. Geochemical behavior of metals in the sediments is dependant on grain size, in part, but might be much controlled by complex submarine topography, highly varied tidal currents and surrounding land geology in the study area. Igeo (index of geoaccumulation) representing metal condensation in the sediments moderately/strongly polluted in Co and Cr and moderately polluted in Cu and Ni. But notable metal condensations are not found in the study area. So, it might be interpreted that grain size and metal content distribution tendencies in the sediments are considerably influenced by complex submarine topography, highly varied tidal currents and surrounding land geology.

• The Korean Journal of Quaternary Research
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• v.16 no.1
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• pp.17-27
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• 2002

Analysis of No. 199∼145 cross-sections set up by the Ministry of Construction (1978) in the middle reaches of the Sumjin River around Sunchang, Daegang, and Goksung areas have been done for delineating the changes In fluvial geomorphic features. The entire river-bed in the study area has been considerably degraded since 1978. In some cross-sections, the thalweg shillings are observed. Two aspects are responsible for the erosion-dominant environment. First, flow velocity has been increased. Human activities including wetland destruction, ex-channel destruction and artificial levee construction reduced the channel width, and fixed the channel geometry. This has resulted in increase of the water velocity. Pebble and granule∼coarse sand are prevailing on the river-bed, indicate the high speed of the currents. Second, aggregate has been intensively mined during 1980s∼1990s around the areas. Especially, in the right side of the cross-sections No. 188∼187 and the left side of the cross-section No. 155, erosion toward under the artificial levee is remarkable. This can be led to bank failure in case of heavy rainfall.

• Journal of The Geomorphological Association of Korea
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• v.18 no.4
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• pp.203-212
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• 2011

The objective of this paper is to identify the present-day surficial sediment distribution patterns of the tidal river, Gongneungcheon, through the grain size and statistical analysis. Four major findings of this study are as follows; First, the composition of sediments over the study area are mainly silt in texture. Second, the surficial sediment distribution reveals that grain size becomes coarser as they approach seawards not only in summer but also in winter. It can be concluded that tidal flows play a significant role, especially in winter, in the distribution of surficial sediments in Gongneungcheon. However, samples obtained in summer were relatively small in mean size and showed better sorting compared to those obtained in winter. Third, the mean sizes of the samples on the transects decrease as the distance from the channel increases. Finally, the artificial structure such as a floodgate affects the distribution of the sediments.

• Economic and Environmental Geology
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• v.42 no.2
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• pp.107-120
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• 2009

Spacial variation in organic components and temporal variation in the origin was examined through the organic geochemical (TC, TN, TS, $CaCO_3$, TOC, C/N, and $\delta^{13}C$) and pyrolysis analysis (HI, OI, and Tmax) in the core sediments which were acquired in the continental shelf of the South Sea close to Seomjin River. Levels of TC, TN, and TS show relatively low and constant in the core SJ03 located close to the Seomjin River mouth, while those are increased a little with being varied with low amplitude in the core SJ02 and SJ04 acquired at the middle of inner shelf area. They fluctuated with high amplitude in the core SJ01 and SJ05 near to the outer boundary of inner shelf. The vertical characteristics of organic components in the core SJ01 acquired at the outer boundary show that the area has undergone distinctly the environmental change at 9.0 kyr B.P. After 9.0 kyr B.P., Levels of TC, TOC, TN, $CaCO_3$, $\delta^{13}C$, HI, and Tmax are rapidly increased, while C/N and or are significantly decreased. Even though the contents of organic components are not high, such a changes reflect that the terrigenous organic matters were predominant before 9.0 kyr B.P due to the influence of Seomjin River, but after then, the marine organic matters have dominated due to the inflow of the Tshusima current.