• 한국지구과학회지
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• 제27권5호
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• pp.548-556
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• 2006

본 연구는 경안천 유역에 발달한 유물 지형인 하성면의 퇴적층을 모재로 하여 형성된 토양 특성을 밝히는 데 있다. 조사 지점의 적색토의 A층은 적갈색(5YR/4/3)의 미사질식토로 발달도가 미약한 아각괴상 내지 입상 구조이다. B층은 황적색(5YR4/3) 내지 명적색(2.5YR4/6)의 미사질식토로 발달도가 약한 아각괴상 구조를 보이며 적색의 점토 피막과 망간결핵이 나타나는 점토 집적층의 특징을 갖는 argillie층이다. 토층은 $A_1-B_{1t}-B_{2t}-C$ 층으로 되어있다. 하성 고위면의 퇴적층을 모재로 발달한 본토양은 과거 제4기의 온난한 생물기후 상태하에서 이루어진 강력한 탈규산화 작용과 염기용탈 및 적색토화 작용에 의하여 생성된 고적색토의 일종으로 판단된다. 따라서 본 적색토는 현재보다 온난한 생물-기후상태하에서 탈규산화를 동반하는 적색토화 작용에 의하여 형성된 고적색토로 판단된다.

• 한국석유지질학회:학술대회논문집
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• 한국석유지질학회 2000년도 제7차 학술발표회 발표논문집
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• pp.47-56
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• 2000

The northwestern part of Kyongsang Basin largely comprises interbedded sandstone and mudstone with local conglomeratic deposits in the basin margin, representing marginal alluvial fans and fluvial depositional environments. The non-marine successions are divided into successive stratigraphic units, each of which is unique in facies assemblages and architecture of sandstone bodies. Two stratigraphic units, i.e., Sinpyong-Anpyong and Jotap units are examined in terms of stratigraphic architecture and its causative processes. Detailed architectural analysis reveals that the channel systems of Sinpyong-Anyong unit were of braided patterns, whereas those of Jotap unit were dominated by small-scale bedforms. The difference in fluvial styles can be attributed to the changes in amount and caliber of sediment load and water discharge, which might have been ultimately governed by basin tectonics, climate, and base level. Along with the marked change in fluvial style, the two successive units show repeated expansions of distal, water-logged floodplains and lacustrine facies in the basal and uppermost parts of Sinpyong-Anpyong unit, where the proportion of channel sandstone bodies is relatively low. These stratigraphic intervals are succeeded by the sequences with proximal, well-drained floodplain facies and relatively coarser-grained channel sandstone bodies of higher proportion, reflecting the progradation of proximal systems (the middle part of Sinpyong-Anpyong unit and Jotap unit). The overall stratigraphic architecture can be ascribed to the fluctuations in accommodation space and sediment supply induced by repeated basin subsidence.

• 자원환경지질
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• 제27권6호
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• pp.579-592
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• 1994

A case study is presented where a fluvial system is modeled in three dimensions and compared to data gathered from a study of the Arkansas River. The data is unique in that it documents changes that affected a straight channel that was excavated within the river by the U.S. Army Corps of Engineers. Excavation plan maps and sequential aerial photographs show that the channel underwent massive deposition and channel migration as it returned to a more natural, meandering path. These records illustrate that stability of fluvial system can be disrupted either by catastrophic events such as floods or by subtle events such as the altering of a stream's equilibrium base level or sediment load. SEDSIM, Stanford's Sedimentary Basin Simulation Model, is modified and used to model the Arkansas River and the geologic processes that changed in response to changing hydraulic and geologic parameters resulting from the excavation of the channel. Geologic parameters such as fluid and sediment discharge, velocity, transport capacity, and sediment load are input into the model. These parameters regulate the frequency distribution and sizes of sediment grains that are eroded, transported and deposited. The experiments compare favorably with field data, recreating similar patterns of fluid flow and sedimentation. Therefore, simulations provide insight for understanding and spatial distribution of sediment bodies in fluvial deposits and the internal sedimentary structure of fluvial reservoirs. These techniques of graphic simulation can be contributed to support the development of the new design criteria compatible with natural stream processes, espacially drainage problem to minimize environmental disruption.

• 대한지리학회지
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• 제44권3호
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• pp.224-239
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• 2009

본 연구는 오대천 상 하류의 하천 지형 특성을 분석하고, 오대천의 하천 및 하안단구 지형 형성과정에 대해 검토하였다. 오대천은 상류 화강암 지역보다 하류 퇴적암 지역에서 풍화 침식에 대한 저항력이 크기 때문에, 상류보다 하류 유역분지에서 해발고도가 높고, 기복량은 크며, 경사도가 높게 나타난다. 또한 상류보다 하류에서 평균 하곡 폭이 1/3 정도로 좁고, 평균 하도 폭도 더 좁은 것으로 측정되었다. OSL 연대 측정 결과 하안단구 1면의 형성시기는 최종 빙기 최성기인 MIS 2기말의 기온 상승기이며, 하안단구 2면은 최종 빙기 내의 아간빙기에 해당되는 MIS 3기 중반으로 측정되었다. 이를 토대로 하안단구 2면 형성 이후 현재까지 오대천의 평균 하각률은 상류 화강암 지역에서 0.205m/ka 하류 퇴적암 지역에서 0.269m/ka로 계산되었다.

• 한국석유지질학회:학술대회논문집
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• 한국석유지질학회 1999년도 제6차 학술발표회 발표논문집
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• pp.2-16
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• 1999

This study includes structural analysis of the northern Pattani Basin, areal description of depositional facies, and their spatial relationships using 3-D seismic and well data. Well log data indicate that the representative depositional facies of the studied intervals are sandy, fluvial, channel-fill facies encased in shaly floodplain deposits. Seismic responses were predicted from a synthetic seismogram using a model of dominant depositional facies. Peak-to-trough amplitude and instantaneous frequency seismic attributes are used in depositional facies interpretation. Three Intervals A, B and C are interpreted on the successive stratal surfaces. The shallowest interval, A, is the Quaternary transgressive succession. Each stratal surface showed flow pattern variation of fluvial channel facies. Two transgressive cycles were identified in interval A. Interval B also indicated fluvial facies. Depositional facies architectures are described by interpreting seismic attributes on the successive stratal surfaces.

• 한국해양학회지:바다
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• 제8권3호
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• pp.225-236
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• 2003

한강 유역에서 하천과 하구-만의 퇴적환경의 연계성과 한강본류의 퇴적환경의 변화를 연구하기 위해, 230여 점의 표층퇴적물과 70여 점의 부유퇴적물과 수리학적 자료를 분석하였다. 연구지역은 신곡수중보를 기준으로 두 가지 환경(하천, 하구-만)으로 구분할 수 있다. 남한강과 북한강에는 역질 퇴적상이, 한강 본류는 사질과 실트질 퇴적상이 우세하게 븐포하였다. 한강 본류 지역은 신곡수중보에 의한 제한적인 퇴적물 이동과 에너지 환경에 의해 퇴적환경의 변화가 발생하였다. 하구-만 환경에 있어서, 수로와 외해 지역에는 상대적으로 조립한 퇴적물이 우세한 반면에, 연안지역은 세립하고 분급도가 불량한 퇴적물이 우세하게 분포하였다. 하천과 하구-만의 연계성은 인공 구조물에 의한 흐름의 제한에 의해서 영향받기 때문에, 평수기에 각 하천은 개별적인 퇴적환경을 나타내며, 하천과 하구-만의 연계적인 퇴적환경은 조석에 영향을 받고, 하구-만의 전이적인 지역은 하천 방향으로 이동한다. 그러나, 풍수기에 각 하천은 하천 유량의 증가에 의해, 연계적인 퇴적환경을 나타내며, 하천-하구-만의 각각의 전이지역은 외해방향으로 이동함을 시사한다. 보다 자세한 연구를 위해서는 신곡수중보 하류의 하구지역에 대하여 남북한 공동연구가 필요하다.

• 물과 미래
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• 제30권1호
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• pp.101-108
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• 1997

• 물과 미래
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• 제30권2호
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• pp.52-58
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• 1997

• 한국지구과학회지
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• 제26권8호
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• pp.809-820
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• 2005

The fluvial sequence developed along the channel margin of meander bends in the midstream of the Yeongsan River consists of channel deposits at the bottom and overbank deposits at the top, and shows a fining-upward trend. The fluvial deposits consist of 7 sedimentary facies, and facies association forms 7 architectural elements. The channel deposits formed as channel bar or point bar. The channel bar deposits consisted of architectural element of gravel bedform were formed by channel lag deposits within the channel; whereas, the channel bar deposits consisted of architectural elements of downcurrent-dipping inclined strata sets, cross-stratified and horizontally stratified sets, and horizontally stratified sets were formed by downstream migration of sand wave or downstream transport of sand by traction current in the upper flow regime conditions within the channel. The point bar deposits consist of architectural elements of down current-dipping inclined strata sets, horizontally stratified sets, cross-stratified and horizontally stratified sets, and laterally inclined and horizontally stratified sets. These architectural elements are thought to have been formed by the combined effects of the migration of sand dunes and the formation of horizontal lamination in the upper flow regime plane bed conditions. The overbank deposits consist of the architectural elements of overbank fine and sand sheet and lens. The overbank fines were formed by settling of mud from slackwater during flooding over floodplain whereas the sand sheet and lens were formed by traction of sands introduced episodically fiom channel to the overbank during flooding.

• 한국지형학회지
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• 제24권2호
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• pp.27-40
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• 2017

This study tries to analyze topographic distribution and characteristics of as well as formative age and incision rate of fluvial terraces in Danyang River on western side and Geum River on eastern side of the northern Sobaek Mountains and to estimate geomorphic development during the late Quaternary in the mountains regarded as one of the uplift axes in the Korean Peninsula. OSL age dating shows that the fluvial terrace I with an altitude above riverbed of approximately 7~13 m in Danyang River has a formative age of approximately 18 ka (MIS 2) and incision rate in the river is approximately 0.156~0.194 m/ka based on the age. Altitudes above riverbed of the fluvial terrace I in Geum River range from approximately 7 to 14 m and the terrace is thought to be older than 70 ka based on age result from aeolian sediments above the terrace deposits, suggestive of an incision rate less than approximately 0.10 m/ka. These results indicate lower uplift rate in the northern Sobaek Mountains than in the Taebaek Mountains. Moreover, it can be suggested that the northern Sobaek Mountains has experienced asymmetric uplift during the late Quaternary, because the river on western side of the northern Sobaek Mountains shows greater uplift rate than the eastern side river does. Low incision rate in Geum River can be attributed to low altitude of the river basin with little difference in altitude from the base level as well as to gentle river slope due to influence of Nakdong River.