• 자원환경지질
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• 제3권3호
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• pp.177-186
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• 1970

Bupyong lead-silver mine is located at outskirt of Inchon, a harbor city on the Yellow Sea about 40 km due west of Seoul. The geology of the area is composed of gneisses of pre-Cambrian age, rhyolite of Jurassic to Cretaceous age which extruded over the gneisses and late Cretaceous granite. Small diabasic dike is observed only in the underground. The contact plane between overlying rhyolite and underlain gneiss is sinuous and generally pitches about $30^{\circ}{\sim}40^{\circ}$ toward east. Conjugate joints and fissures are well developed in the rhyolite striking generally north-southward. Three ore bodies are being exploited and three more are under prospecting. These ore bodies range from few tons of hundred thousand to million tons in reserve. These ore bodies occur exclusively in the rhyolite along joints as network and/or desseminated type. The lower limit of ore bodies is always delineated at about 20~30m above the gneiss which might be indicative of ore genesis that has not been clearly explained so far. Two hypothesis on ore genesis could, however, be considered: firstly lithologic difference in the rhyolite might be a manifestation of different flows along which ore solution ascended and replaced along joints; secondly diabasic dike has acted as ore bringer since the dike contains considerable amount of silver, lead and zine. Ore minerals are galena and native silver accompanied by pyrite, argentite, pyragyrite and magnetite. It is believed that pyritization took place in advance to main mineralization, and ore deposit is classified as meso- to epi-thermal type.

• 한국산학기술학회논문지
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• 제13권9호
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• pp.4326-4333
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• 2012

새만금 방조제 건설기간에 해당하는 2001년부터 2010년까지 10년간 새만금 수역에서 식물플랑크톤 현존량을 조사하였다. 식물플랑크톤 현존량은 조사 시기 및 조사 정점에 따라 57 - 85,219 cells/ml의 큰 변화를 보였다. 새만금호 내부 수역은 담수 및 해수의 유입량 변화와 계절변화에 기인하여 식물플랑크톤 현존량이 시공간적으로 변화하였다. 한편, 담수 정점들은 상시적으로 높은 현존량이 기록되어 녹조발생이 잦았으나 방조제 밖 해수역의 현존량은 보편적 범위에 있어왔다. 장기적 관점에서 방조제 물막이 공사 완공(2006년 4월)을 전후하여 비교할 때 식물플랑크톤 현존량의 큰 변화는 나타나지 않았다.

• 한국해안해양공학회지
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• 제10권1호
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• pp.10-17
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• 1998

다양한 공사가 진행되는 금강하구의 수동역학 변화를 조석 및 조류 그리고 수심변화등의 관측자료를 중심으로 해석하였다. 2년여에 걸쳐 수집된 수심측정 자료를 분석한 결과, 군산외항부근의 도류제 축조구간에서는 뚜렷한 조류속도의 증가와 연평균 50 cm에 다다르는 세굴이 진행되는 것이 확인되었다. 그러나 군장산업단지조성호안공사 및 새만금4호 방조제 축조 내면 간사지에서는 가을철 2개월에 30cm의 퇴적이 관측되는 등 유속의 둔화와 함께 퇴적이 급속히 진전되는 현상으로 수동역학의 전이 현상이 나타나 공사로 인한 금강하구의 수동역학체계는 매우 급격하게 변화됨을 보인다

• 한국항만학회지
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• 제13권1호
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• pp.133-146
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• 1999

Mokpo coastal area is connected to the adjacent a long river and two large basins. It is essential for port planning coastal zone management and environmental impact study to analyze the data related to the ship operation and variation of current and water quality due to the development of water area including dredging reclamation and estuary barrage. The Yongsan river estuary weir and Yongam-Kumho basins discharge much of water through water gates for the purpose of flood control and prohibit salt intrusion at the inland fresh water area. To meet this purpose discharge through the gates have been done at the period of maximum water level difference between inner river and sea level. This discharged water may cause the changes of current pattern and other environmental influences in the vicinity and inner area of semi-closed Mokpo harbor. In this study ADI method is applied to the governing equation for the analysis of the changes on current pattern due to discharged water. As the results of this study it is known that the discharging operation causes many changes including the increase of current velocity at the front water area at piers approaching passage and anchorages. Discussion made on the point of problems such as restricted maneuverability and the safety of morred vessels at pier and anchorage. To minimize this influence the linked gate operation discharging warning system and laternative mooring system are recommended.

• 한국해양환경ㆍ에너지학회지
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• 제11권4호
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• pp.199-213
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• 2008

2006년 4월 새만금의 외곽 방조제가 완전히 체절됨에 따라 방조제 내부수역은 염수호수로 전환되었다. 방조제가 조성되는 과정 동안 호수의 수질 변화를 조사하기 위하여 1999년부터 2007년까지 4회의 고정 관측과 13회의 공간 관측이 이루어졌다. 조사 기간 동안 염분, 부유물질, 영양염(DIN, DIP, DISi), 엽록소-$\alpha$를 분석하여 방조제 조성 이후 초기의 수질 변화를 집중적으로 검토하였다. 방조제 체절로 인해 내측의 호수에서 조석의 약화는 저층 퇴적물의 재부유현상을 약화시켰고, 수중의 부유물질 농도를 감소시켰다. 이로서 태양광이 수층의 깊은 곳까지 침투할 수 있게 되었고, 자연히 식물플랑크톤의 광합성이 증가되었을 것이며, 이러한 현상은 엽록소-$\alpha$의 농도가 약 2배 정도 증가하는 결과로 나타났다. 식물플랑크톤의 급격한 성장과 수중의 부유물질의 농도 감소는 표층수의 DIP 농도를 더욱 감소시키는 결과로 나타났고, 이에 반해 표층수의 DIN과 DISi는 방조제 체절 이후 새만금호 내에서 확장된 담수의 영향과 저층에서의 공급으로 인하여 식물플랑크톤의 소비에도 불구하고 체절 이후에 증가한 것으로 평가되었다. 이에 따라 수중의 N/P 비율이 급격하게 증가하게 되었고, DIP가 일차생산의 제한인자로서 작용하게 되었다. 결과적으로 새만금호는 방조제의 체절로 인하여 과거에 전형적인 대조차 연안환경에서 DIP가 일차생산의 제한인자로 작용하는 기수환경으로 전환되었다. 금강 하구언 조설 이후 금강하구에서도 동일한 현상이 나타났으나, 새 만금호수의 경우 현재까지 해수 유통이 계속되고 있기 때문에 염수쐐기현상을 통해 저층으로 유입한 해수로 인해 염분 성층이 발생한다면 여름철에 저층에 국부적인 빈산소층이 발생할 가능성이 있으므로 이에 대비한 집중적인 감시가 필요하다.

• 한국농공학회지
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• 제40권5호
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• pp.43-51
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• 1998

In design and management of sea0dikes, engineers need to study various transient seepage conditions through dikes not only for the sea water infiltration into dikes due to cyclic rises of sea water level also for the seepage flow out from dikes toward the sea due to cyclic drawdown of sea water level. Characteristics of seepage flow toward the sea from dikes are more complicated than as known and remained unclearly. The case of such seepage flow may be explained by figuring out seepage characteristics in filter as a part of sea-dikes. Filters in most sea-dikes in Korea are inevitably placed with reversely inclined shape due to field construction conditions. Most computer programs for seepage analysis based on the various numerical methods give practically acceptable results, but for the case of reversely inclined section of filters any verification to apply them might be needed. In this study, large scaled model tests were executed to verify and understand seepage flow through earth-filled sea-dikes. The results from numerical analysis and model tests show some remarkable differences in pore pressure distribution under cyclic changes of see level, and some of the results need to be considered in design and construction practices with further study.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.992-996
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• 2004

천해역(shallow sea area)에서의 조류 형태(tidal flow regime)는 주로 만(bay)이나 해안선(shoreline)의 형태, 해저 지형(bottom topography), 수로(channel), 천퇴(sand bar)나 간석지(tidal flat) 등의 지형적인 요인에 의해 결정된다. 본 연구는 복잡한 지형적 변화 및 천해특성에 기인된 조석(tide)의 현상이 뚜렷이 나타나는 금강하구(Keum River Estuary)를 하구둑(Estuary Dike) 건설 전${\cdot}$후(Before and After Constructed)의 수심(depth)변화 및 유속(current)변화를 수치실험(numerical experiments)으로 고찰했다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.272-277
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• 2005

Initial mixing characteristics in near field regions were analyzed by FLOW-3D, for analyzing mixing behavior of submerged discharge from freshwater lake in sea water. FLOW-3D model was applied to the region near Geum-ho dike for its verification. Simulation results from FLOW-3D were compared to the observed data for the verification periods. FLOW-3D showed resonable prediction results compared to the observed data, except underestimation in area near outfall. Particularly, FLOW-3D showed a good prediction for movement of buoyancy jets. In addition, FLOW-3D model was applied to the region near Saemangeum dike, which is to be constructed in near future. It was expected that the results of model application to Saemangeum area could provide substantial information in planning submerged discharge facilities. Based on the model applications to Saemangeum area, it was recommended that outfall should be located to the distance which gave an enough depth of outfall from water surface.

• 기술사
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• 제33권4호
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• pp.68-71
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• 2000

Tideland reclamation in Korea has significant meanings both in securing the staple food supply and in enlarging the limited land resources. Environmentally, that significantly contributes in protecting the sea and the tidelands connected to a reclaimed area from the direct exposure to the environmental destruction by filtering the large volume of contaminant discharged from the inland. Furthermore, within few years after closing a sea dike. formulation of new tideland begins in wide area in front. Therefore, tideland reclamation should not be the one that must be unconditionally objected. Instead, the methodology should be wisely redirected to minimize the environmental disorder. It will be one viable alternative to proceed the tideland reclamation at medium- to small-scales environment-friendly bringing minimal environmental change in the sea.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.133-136
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• 2002

A simulation by the TOPAS model, two dimensional finite difference model was performed on the flows through drainage lock gate for the Saemangeum tidal reclamation project. Analysis focus on the changes of intertidal zone areas according to the operation scheme of the gate. The intertidal zone areas were analyzed as $66{\sim}70\;km^2$ when the opening of the gate was 300 m. It occupied about $85{\sim}90%$ of intertidal zone areas compared to that the Mangyung sea basin was opened without sea-dike. It appeared to be the most effective in terms of securing enough intertidal zone areas when the gate was operated as inflowing sea-water after 2 day's drainage.