• 한국농공학회논문집
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• 제53권6호
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• pp.43-50
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• 2011

The fractal method has recently been applied to a model for determining soil grain size distribution. The objective of this study is to review the applicability of the fractal method for a analysis of submarine sedimentary environments by comparing fractal constants with grain size statistical analysis for the soil samples of Pohang (PH) and Namhae (NH). The y-interception of log (grain size)-log (passing) equation was also used because grain size distribution couldn't be expressed with fractal dimension only. The result of comparison between fractal constants (dimension, y-interception) and grain size statistical indices, the fractal dimension was directly proportional to the mean and the sorting. And the y-interception showed high correlation with the mean. The fractal dimension and y-interception didn't show significant correlation with the skewness and the kurtosis. Thus regression equations between fractal constants and two statistical indices (mean, sorting) were derived. All classifications of the mean and the sorting could be determined using the regression equation based on the fractal dimension and y-interception. Therefore, fractal constants could be used as an alternative index representing the sedimentary environments instead of the mean and sorting.

• 환경영향평가
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• 제18권3호
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• pp.171-183
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• 2009

This study aims to analyze the sedimentary environment change in mid-channel bar of the lower Geum river basin after the construction of the estuary barrage using multi-temporal satellite data and GIS. The sedimentary environment changes were observed in mid-channel bar areas. The mid-channel bar F was found to have been newly formed for 10 years(1996-2006), whereas the mid-channel bar B located between mid-channel bar A and C has disappeared by erosion during the same periods. When examined by section, the areas of the mid-channel bar in the upper stream section from the Yipo's reference point generally increased due to the prevailing sedimentary environments, and those of the downstream section decreased where corrosive environments are dominant. In ternms of the centroid movement, the mid-channel bars grew up toward the downstream by switching erosion and accumulation, as sedimentation was prevailing in the downstream area of mid-channel bars and corrosion was dominant in the upper stream. Through grain size analysis, the study areas are divided into three sections according to the average grain size. In Section I, the mid-channel bars were formed as a result of sedimentary process of tides in the past. In Section II, the mid-channel bars were formed partly through the sedimentary process of rivers although the sedimentary process of tides is prevailing. In Section III, the mid-channel bars were formed mainly through the sedimentary process of rivers, even if it showed the sedimentary process of tides in the past.

• 한국지형학회지
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• 제25권2호
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• pp.43-61
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• 2018

Heterogeneous sedimentary deposits with different soil colors and various degree of hardness are exposed in its foredune and tidal zone due to the effects of recently accelerated coastal erosion along the Ujeon Coast in Jeung-do, Shinan-gun. This study was conducted on the assumption that these sedimentary deposits were developed in different timing and environments. Thus, we can infer the geomorphic development processes of the area based on evidences like the physicochemical characteristics of each sedimentary layer. Several analysis of these sedimentary depositssuch as grain size analysis, X-ray Fluorescence Measurement (XRF), and Loss on ignition (LOI) were performed on central (Ujeon A) and southern (Ujeon B) parts of the Ujeon Coast. I found that the foredune sedimentary deposits have four stages of geomorphic development processes. In the initial stage of development, during the peak of the Last Interglacial Period (MIS 5e), basal deposits were accumulated in the low-energy environment of subtidal zones. In the second stage, during the Last Glacial Period (MIS 4~MIS 2), eolian sedimentary layers were developed by terrestrial aeolian processes by which fine materials were transported from the Yellow Sea which became a dry land exposed by lowered sea level. In the third stage, various mechanism existed for the formation of each sedimentary layer. In the region of Ujeon A, sedimentary layers were developed in the littoral zone environment dominated by marine processes during the maximum phase of transgression in the Holocene. Meanwhile, the region of Ujeon B began to form eolian sedimentary layers during MIS 2. In the last stage, thick coastal dune deposits, covered all over the Ujeon Coast. During the late Holocene (0.7~0.6 ka), terrestrial processes kept dominating the region, developing typical eolian sedimentary layers.

• 한국지형학회지
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• 제25권3호
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• pp.43-55
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• 2018

This study aimed to identify different sedimentary environments of Gochang coast according to geomorphic conditions of each bore hole. To achieve the aim, this study utilized the classification of sedimentary environmental conditions of surface sediment, which was based on grain size distribution characteristics.In other words, three sedimentary environmental conditions ofsandy flat + sand beach, coastal sand dune and weathered bedrock soil, which were distinguished based on grain size distribution characteristics of mean-sorting for surface sediments, were applied to the sediments of bore holes. Four sedimentary environments could be identified in Gochang coast. First, the lake sedimentary environment originated from terrestrial sediments seems to have been dominated by weathered bedrock soil that the surface flow has deposited in a coastal wetland or a boundary, which is affected by the sea. Second, the lake sedimentary environment that is little affected by coastal sand dunes is located at the center of a valley, which is connected to the land, and the dune slack of Saban-ri. The surface flow of weather bedrock soil is the main source of deposits. However, there seems to have been a temporary influence of the sea. Third, the lake sedimentary environment that is strongly affected by coastal sand dunes is located at the dune slack of Yeongjeong-ri. This environment shows traces of a change from a coastal sand dune into the dune slack. Finally, the coastalsand dune sedimentary environment, which wasinvestigated by boring the current coastal sand dune, shows a temporary influence of the land but seems to have maintained the overall stability. Consequently, this study demonstrated that the grain size distribution characteristics of the present surface sediments could be effectively applied to identify the sedimentary environments of the paleo bore hole sediments. In addition, the paleo change of sedimentary environment could also be identified in many places of Gochang coast. If the results of this study are combined with the age dating and geochemical analysis in future works, the paleo environmental change in Gochang coast will be restored more precisely.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.140-143
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• 2004

The west coast of the Korean Peninsula is famous for its large tidal range (up to 9 m) and vast tidal flats. With comparison the sedimentary environments of open and close tidal flat using remote sensing, we select Kanghwa tidal flat and Hwang-Do tidal flat in Cheonsu Bay. Prior to surface sediment discrimination using remote sensing, sedimentary environments including intertidal OEM, hydraulic condition, and relationship between grain size and various tidal condition are investigated. Remote sensing has the potential to provide synoptic information of intertidal environments. The objectives of this study are: (i) to generate an intertidal digital elevation model (OEM) using the waterline method of Lansat TM/ETM+, (ii) to investigate the tidal channel distribution using texture analysis, and (iii) to analyze the relationship between surface grain size by using in-situ data and intertidal OEM and tidal channel density by using high-resolution satellite data such as IKONOS and Kompsat EOC. The results demonstrate that satellite remote sensing is an efficient and effective tool for a surface sediment discrimination and long term morphologic change estimation in tidal flats.

• 자원환경지질
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• 제54권5호
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• pp.595-603
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• 2021

하천 및 육상 골재 자원의 주 대상인 모래층의 분포는 제4기 퇴적 환경 중 충적 및 하천 퇴적환경에 주로 속한다. 충청남도 금산군 일대의 골재 자원 분포는 특징적으로 감입곡류 하천이 우세한 퇴적 환경 중심으로 발달하고 있는 반면, 붕적이나 선상지성 퇴적환경에서 형성된 퇴적층은 육상 및 하천 골재 분포 비율이 상대적으로 낮다. 봉황천 주변과 소하천들이 합류하는 부근 일대는 소규모이지만 하천의 범람원이 발달하며 골재 분포 지역에 해당된다. 금산군 제4기 퇴적층의 수직 분포는 약 5~12m 범위와 평균 8m의 제4기 퇴적층 두께를 갖는다. 골재 부존 구간은 평균 3.6m 두께이며 평균 입도는 점토-실트 약 21%, 모래 67%, 그리고 자갈 12%이다. 골재 부존 구간의 주요 특징은 조립질 모래가 우세하고 자갈은 아각형 또는 아원형, 분급은 일반적으로 불량하고 괴상의 형태를 띠며 암회색~황갈색 범위의 토색을 보인다. 금산군 내에서 골재 개발 가능성이 큰 분포 지역은 금강본류, 봉황천과 소하천 지류의 현 하상과 구하상을 따라 분포하는 충적 퇴적층 및 하천 퇴적층이다.

• 한국습지학회지
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• 제7권2호
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• pp.53-67
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• 2005

천수만은 전형적인 반 폐쇄형만으로 수로, 사퇴, 작은 섬 그리고 갯벌 등 다양한 환경들이 있다. 1983년에서 1985년 사이에 건설된 서산 A와 B 방조제는 천수만 북부의 퇴적환경을 지속적으로 변화시켰을 것으로 보인다. 황도 갯벌과 주변 해역의 퇴적환경을 파악하기 위하여 2003년 6월과 10월에 표층과 주상 퇴적물을 채취하였다. 표층 퇴적물은 5개의 퇴적상으로 구성되어 있었다. 일반적으로 10월의 표층퇴적물은 6월과 비교하여 갯벌은 조립해 졌으나 주변 해역은 거의 변화가 없었다. 3개의 주상퇴적물의 퇴적상은 황도 주변 갯벌은 파랑과 조류 에너지가 상대적으로 높고, 조수로 근처의 갯벌은 에너지가 상대적으로 낮은 것으로 나타났다. 황도 갯벌의 11개월 동안 단기 퇴적률은 중앙지역은 퇴적 되었으나, 갯벌의 동쪽 측면과 서쪽 측면은 침식된 것으로 나타났다. 이는 방조제에 의하여 조류 형태와 퇴적물 순환이 변화되었기 때문으로 보인다.

• 한국해양학회지
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• 제26권1호
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• pp.13-23
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• 1991

한공종합개발 휘 한강하구 및경기만에서의 퇴적환경을 파악하기 위하여 수리물리 적 및 퇴적학적 관점의 수사를 실시하였다. 수리적 특정과 퇴적학적 특성을 종합해 볼 때, 본 연구지역은 크게 \circled1 행주대교 상류역의 하천, \circled2한강과 경기만을 연결하는 하 구, \circled3 경기만 일대의 연안-만 퇴적환경으로 구분할 수 있다. 그러나 한강종합개발 이 후 한강 전역에서 통수단면적이 증가되고 유속이 감소되는 등 전반적인 수리물리적 특 성이 변화됨으로써 한강하류 및 하구역(강화대료)에서의 부유물질 농도가 각각 37mg/l, 500-1750 mg/l에서 개발이후 17 mg/l 208-1142 mg/l 로 큰 폭으로 감소된 것 으로 나타났다. 또한 하류 수중보 부근에서는 siltation이 유발되고 있으며, 하천환경 과 하구환경의 경제가 점이 적이지 못하고 급격한 변화를 보이는 등 퇴적환경에도 상 당한 변화가 초래된 것으로 나타났다. 이는 주로 종합개발에 수반되는 한강의 수위저 하를 방지하기 위하여 잠실대교와 신곡에 수중보를 설치함으로써 비롯된 것으로 사료 된다. 하구는 하천과 해양을 연결하는 전이지역이므로, 한강과 한구에서의 이러한 변 화는 앞으로 인접한 퇴환경에도 많은 영향을 미칠 것으로 사료되며, 경기만으로 파급 되는 영향을 파악하기 위하여는 무엇보다도 임진강과 예성강 하구를 포함한 한강 하구 역에 대한 상세한 연구가 요구된다.

• 자원환경지질
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• 제18권3호
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• pp.289-299
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• 1985

Sedimentary petrology and depositional environments of the Sindong Group, consisting of in ascending order the Nagdong, Hasandong and Jinju Formations, in the Euiseong Subbasin are studied. For these, the Sindong sequence over 1,000m thick is measured at the scale of 1:200 and 36 thin sections of sandstones of the Hasandong Formation are studied under the polarizing microscope. In addition, published paleontologic data are incorporated in the sedimentologic interpretation. Most of the sandstones are classified as arkose. They are moderately sorted, near symmetrical to fine skewed and mesokurtic. Relationship between the textural parameters suggests a fluviatile environment of the Hasandong Formation. The Sindong fauna and flora also indicate non-marine depositional environments. Sedimentologic data of the measured sections show that the Sindong Group is made up of from the bottom an alluvial fan (lower part of the Nagdong Formation), a fluvial plain (upper part of the Nagdong Formation and the Hasandong Formation) and a fluvial/lacustrine (the Jinju Formation) deposits.

• Ocean and Polar Research
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• 제29권4호
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• pp.411-418
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• 2007

We studied the bottom morphology and sedimentary environments of the Masan Bay using high-resolution Chirp seismic profiles and sediments data. According to deep-drilled core samples (up to 20 m thick) penetrated into the weathered rock basement, the sediments consist largely of three sediment types: the lower sandy gravel facies (Unit I) of 1-4 m in thickness, the middle sandy mud and/or muddy sand facies(Unit II) of 1-2 m thick and the upper mudfacies (Unit III) of over 10 m in thickness. The sedimentary column above the acoustic basement can be divided into two major sequences by a relatively strong mid-reflector, which show the lower sedimentary sequenc e(T) with parallel to subparallel internal reflectors and the upper sedimentary sequence(H) with free acoustic patterns. Acoustic basement, the lower sedimentary sequence (T), and the upper sequence (H) are well correlated with poorly sorted massive sandy gravels (Unit I), the sand/mud-mixed sediment (Unit II), and the muddy facies(Unit III), respectively. The acoustic facies and sediment data suggest that the Masan bay is one of the most typical semi-enclosed coastal embayments developed during the Holocene sea-level changes. The area of the Masan Bay reduced from about $19\;km^2$ in 1964 to about $13\;km^2$ in 2005 by reclamation, and its bottom morphology changed as a result of dredging of about $2{\times}10^7\;m^3$.