• Title/Summary/Keyword: 퇴적환경의 변화

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인천 송도 신도시 조성을 위한 갯벌매립이 해양저서동물 군집에 미친 영향 3. 변화된 환경요인과 군집구조와의 관계

  • 홍재상;이창근
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2000.05a
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    • pp.410-411
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    • 2000
  • 연안 매립을 포함하는 방파제의 건설이나 호안의 축조는 자연적인 해류의 흐름을 방해하는 인위적 교란으로서 그에 따른 수력학적 변화에 의해 퇴적학적 특성은 물론 지형학적 변화를 유발하게 된다. 이러한 물리적 환경의 변화가 저서생물의 유생의 분포. 먹이 입자의 퇴적작용, 그리고 퇴적상의 변화를 초래하고 결국 저서동물군집의 구조에 변화를 주게 된다(Seys et al., 1994). (중략)

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관광동굴의 환경변화와 보전에 관한 연구

  • 홍시환
    • Journal of the Speleological Society of Korea
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    • v.15 no.16
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    • pp.17-37
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    • 1987
  • 동굴이 관광개발되면 반드시 그 환경은 변화되기 마련이다. 동굴이 관광개발된지도 벌써 20년의 세월이 지났다. 따라서 이 동굴의 개발은 마침내 많은 환경변화를 가져오게 하였다. 원래 동굴의 오염과 오손의 현상은 크게 퇴적물공해와 환경공해의 두가지로 대별되는데 그중 퇴적물공해에는 파손공해, 녹색공해, 그리고 흑색공해, 박리공해 등의 네가지로 구분된다.(중략)

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Importance and Application of Ichnology (생흔학의 중요성 및 활용)

  • Kim, Jong-Kwan;Chun, Seung-Soo;Baek, Young-Sook;Chang, Eun-Kyong;Shin, Sun-Ja
    • The Korean Journal of Petroleum Geology
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    • v.12 no.1
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    • pp.34-42
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    • 2006
  • Ichnology is the study of traces made by various organisms, which includes classification and description of traces, and interpretation of sedimentary process, behavior of organism and depositional environment based on traces and organism behavior. Ichnofacies, which is defined as the association of several traces related together with substrate characteristics and sedimentary processes, is closely related to depositional environment. Ichnology has been applied to sedimentology (to understand physical characteristics of depositional environment, sedimentation pattern and event bed), sequence stratigraphy (to recognize sequence boundaries and biostratigraphic discontinuities such as MFS, TSE and RSE), oil exploration (providing of many information without big cost) and palaeocology. Preliminary ichnological study on the Ganghwa intertidal flat shows that dominant ichofacies are changing with season and location, suggesting that their seasonal variation would be a good indicator to understand the seasonal change of sedimentary processes, the small- scale change of sedimentary environment and the preservation potential of such units. Ichnology on intertidal flat in western coast of Korea has a great potential to apply its results to petroleum geology as well as sedimentology.

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Change in Distribution Characteristics of Surface Sediments of Weir Section in Nakdong River (낙동강 수계 보 구간 표층 퇴적물의 분포 변화)

  • Lee, Kwon Chul;Kim, Hyoung Geun;Lee, Hye Yun;Yang, Deuk Seok;Kim, Shin
    • Korean Journal of Ecology and Environment
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    • v.53 no.4
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    • pp.355-364
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    • 2020
  • This study was carried out to investigated changes in sediments in the eight weir sections of Nakdong River. Sediments were collected and analyzed for Grain Size, Ignition loss, Total Organic Carbon, Total Nitrogen, Total Phosphorus, and Meta. The upstream of the weir was found that fine-grained sediments have repeated increases and decreases. It was found that coarse-grained sediments were being maintained in the downstream part of the weir. The sediments Ignition Loss, Total Organic Carbon, Total Nitrogen, Total Phosphorus are strongly correlated with Grain Size, and these increased at the point where sediments are fine. In the case of metal, the concentration increased across the board, and the correlation with Grain Size, Ignition loss, Total Organic Carbon, Total Nitrogen, and Total Phosphorus was weak. Although there were some sections where fine-grained sediments, organic materials, nutrients, metals increased in the Nakdong River, the overall pollution level is considered weak.

Sedimentary Characteristics in the Tidal Flat of Janghwa-ri, Kangwha Island, Eastern Yellow Sea (강화도 장화리 조간대의 퇴적 특성)

  • Oh, Jae-Kyoung;Do, Jong-Dae;Jo, Yong-Gu
    • Journal of the Korean earth science society
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    • v.27 no.3
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    • pp.328-340
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    • 2006
  • In Janghwa-ri of Kanghwa Island morphological changes in four transects, 112 surface, and 2 core sediments were analyzed to understand the seasonal variation of the muddy tidal-flat environment. Sedimentary of facies can be classified into four facies; sand, muddy sand, sandy mud, and silt. During winter, the coarse-grained sediment facies expanded seaward. In the subsurface part of the core sediments, poorly sorted silty sediments dominate the area. According to the Pb-210 isotope analysis, accumulation rates of the tidal flat in Jangwha-ri appear to be $5{\sim}19mm/yr$. In the study area, the result is suggestive of a rapid change in depositional environments in recent years.

Sedimentary Facies and Environmental Changes of the Nakdong River Estuary and Adjacent Coastal Area (낙동강 하구와 주변 연안역의 표층 퇴적상 및 퇴적환경 변화)

  • KIM Seok-Yun;HA Jeong-Su
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.3
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    • pp.268-278
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    • 2001
  • To investigate sedimentary facies and environmental changes of the Nakdong River Estuary and its adjacent coastal area, the grain size analysis and measurement of organic matter, calcium carbonate, clay mineral and metallic elements were carried out for forty surface sediment samples. Based on regional distribution pattern and characteristics of the surface sediments, sedimentary facies in the study area can be divided into sand facies (TYPE I), mud facies (TYPE II) and sand-mud mixed facies (TYPE III). TYPE III is the transition of TYPE I and TYPE II in every aspects of sediment characteristics. It suggests that TYPE III may have been formed by the mixture of two different source of sediment : one derived from Nakdong River and the other resuspended fine-grained sediments from the Jinhae Bay by winnowing action during floods or storms. Among many aspects of environmental change after the construction of the Nakdong Barrage, the most significant is the increase of sand content off the sand barrier region. It could be explained by several reasons including decreased input of fine-grained sediment from river, increased hydrodynamic energy level off the sand barrier region and artificial effects such as dredging and dumping.

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Characteristics Variation of the Sedimentary Environment in Winter Season around the Baramarae Beach of Anmyeondo Using Surface Sediment Analysis (표층퇴적물 분석을 통한 동계 안면도 바람아래해수욕장 주변의 퇴적환경 변화특성)

  • JANG, Dong-Ho;KIM, Jang-Soo;PARK, No-Wook
    • Journal of The Geomorphological Association of Korea
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    • v.17 no.1
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    • pp.15-27
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    • 2010
  • This study investigated the sedimentary environment changes in the Baramarae beach of Anmyeondo through spatio-temporal surface sediment analysis. In the winter season 2009, surface sediments were classified into 7 sedimentary facies such as gravel, sand, gravelly sand, gravelly muddy sand, muddy sand, silty sand, and sandy silt. Time-series analysis of average grain size from 2002 to 2009 revealed that the average grain size of sediments became finer and sorting was much worse. On the contrary, during the same period, the grain size became coarsening-trend and sorting was much better in beach area. These different grain size patterns resulted from the different change characteristics of beach and tidal flats. The southwestern beach area was connected to the open sea and thus fine sediments were removed by the environments with relatively high-energy. The sedimentation of fine sediments in the bay resulted from the tidal current action and the reduction of energy by the topographic effects. Fine sediments in the outer part of southwestern tidal flats could be explained such that the Seomot isle blocked ocean waves and as a result, low-energy environments accelerated sedimentations of fine sediments.

황해퇴적물중 미량금속의 장기변동에 관한 연구

  • Kim, Pyeong-Jung;An, Gyeong-Ho;Park, Seung-Yun;Heo, Seung;Son, Jae-Gyeong;Kim, Hyeong-Cheol;Hwang, Un-Gi;Lee, Seung-Min;Lee, Wan-Seok
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2008.11a
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    • pp.290-291
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    • 2008
  • 황해 표층퇴적물중 입도(particle size), 비소(As), 카드뮴(Cd), 구리(Cu), 수은(Hg), 납(Pb) 및 아연(Zn) 등의 미량금속 농도변화를 파악하기 위해서 1998년부터 2006년까지 9개년의 조사분석 결과를 요약하면 다음과 같다. 본 연구해역에서 전조사 기간동안 퇴적물의 입도와 미량금속 간에는 유의한 상관관계(P<0.001)를 보였으며, 퇴적물의 입도가 세립 할수록, 수심이 깊을수록 미량금속의 농도가 높은 전형적인 농도분포특성을 보였으며, 전 조사 성분의 농도는 조사해역의 중앙부에서 높은 농도를 보였다. 또한 조사 시기의 변동에 따른 농도 변화보다는 퇴적물의 입도에 따라 중금속농도가 유의하게 변화하는 특성을 나타내었으며, 이는 아마도 퇴적물의 퇴적속도가 매우 낮기 때문에 10여년간의 시간적 변동에 대한 차이를 보이지 않는 것으로 보여진다.

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Sedimentologic Linkage of depositional environments of Han River and Kyunggi Bay, Korea (한강 유역과 경기만 퇴적환경의 연계성)

  • 오재경;방기영
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.3
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    • pp.225-236
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    • 2003
  • In order to understand the relationship of depositional environment between fluvial and estuarine-embayment in Han River system, including depositional change in main Han River, more than 250 bottom sediment and 70 suspended sediment were analyzed with hydrologic data. Based on the previous data, the study area can be divided into two environment(fluvial and estuarine-embayment) by Singok underwater dam. The gravelly facies occurs in the South and North Han Rivers and sandy and silty facies occupies in the main Han River. Depositional environment of main Han River changed mainly because of limited sediment transport and hydrological condition. In the estuarine-embayment environment, coarse-grained sediments are dominant in tidal channel and of shore whereas fine and poorly sorted sediments are observed in coastal area. During moderate period, relationship between fluvial-estuarine-embayment system is discontinuou s because of flow restriction by artificial construction such as dam and underwater dam, so that each river system characterizes the individual environment. Fluvial and estuarine system is influenced by tide and, thus, transition zone of estuarine- embayment system moves landward. During flooding period, however, each river system is integrated as continuous depositional system by high discharge and, thus, transition zone of fluvial-estuarine-embayment system moves seaward. For further detailed systems about the lower Singok under-water dam, joint research of South-North Korea should be necessary.

Sedimentary Environment of Bimodal Shelf Sediments: Southern continental shelf of Korean Peninsula (복모드 대륙붕 퇴적물의 퇴적환경 연구: 한반도 남해대륙붕)

  • 방효기;민건홍
    • 한국해양학회지
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    • v.30 no.1
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    • pp.1-12
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    • 1995
  • The modal analysis was carried out for the total of 216 subface sediments of southern continental shelf of Korean peninsula. Sandy mud or muddy sand distributed in the range of 70∼100 m water depth revealed the bimodal type (sand and mud components). The relations of textural parameters obtained from every modal were consistent with those of shallow marine sediments. The characteristics of sand component between bimodal were as follows: (1) the distributions of mean grain size, sorting, shell content were repeatedly distributed like the directions of depth contour lines. (2) Sand component was composed of medium to fine sand (Mz, 1-3$\psi$) containing many shell fragments, a few pebbles, and iron-stained quartz. (3) The surface of quartz revealed the concordial breakage and V-shaped features formed at high energy environment. (4) In CM-pattern, sand component was plotted in rolling and bottom suspension area. These characteristics imply that sand component probably derives from shoreface sediments deposited at the beach environment.

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