• 제목/요약/키워드: paleosols

검색결과 12건 처리시간 0.119초

Holocene Paleosols of the Upo Wetland, Korea

  • Nahm, Wook-Hyun;Kim, Ju-Yong;Yang, Dong-Yoon;Hong, Sei-Sun;Lee, Jin-Young;Kim, Jin-Kwan
    • 한국제4기학회지
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    • 제17권2호
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    • pp.167-168
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    • 2003
  • The Upo wetland, the largest natural wetland in Korea, is located in Changnyeong-gun, Gyeongsannam Province ($35^{\circ}33'$ N, $128^{\circ}25'$ E), and 70 km upstream from the Nakdong River estuary. Unlike most other Korean wetlands that have been destroyed under the name of economic development, the Upo wetland has been able to preserve its precious ecosystem throughout the years. Thanks to increased public awareness about natural wetlands and environmental conservation, the Korean Ministry of Environment designated the Upo wetland an 'Ecological Conservation Area' on July 26th, 1997. On March 2nd of the following year, the Upo wetland (8.54 $\textrm{km}^2$) was designated a 'Protected Wetland' in accordance with the international Ramsar Treaty. A 4.49m long (from 9.73 to 5.24 m in altitude) UP-1 core ($35^{\circ}33'05"N$, $128^{\circ}25'17"E$), recovered in the marginal part of the Upo wetland, is divided into eight buried paleosol units of different ages on the basis of the abundance of color mottles and vertical color variations (Aslan et al., 1998). Radiocarbon datings suggested that the paleosol profile represent the last 5700 years. The entire section of the core was more or less subjected to pedogenetic processes, and shows very weak to moderate soil profile development. These Holocene paleosols are therefore regarded as synsedimentary soils of deluvium (deposits formed by floods) origin (Sycheva et al., 2003). Unit 1 to 5 paleosols are generally silt-rich and exhibit moderate profile development. The boundaries between the units are somewhat distinguishable, but not so clear cut. This is due to variable repeated combination of accumulation, denudation and soil forming processes within various periods. Mottle textures gradually decrease in abundance with increasing clay content in Unit 6, which results in weak profile development. The lower boundary of Unit 6 lies around about 2000 yrBP, the beginning of Subatlantic in Korea (Kim et al., 2001). Abrupt sediment textural change is detected in Unit 7, which is interpreted to indicate the human activities on the Upo wetland. Unit 8 represents the recent soil forming processes. The preliminary results of this ongoing study imply the primary factor for pedogenetic processes is the water table fluctuations related to the sedimentary textures like grain size distributions, and the geomorphological stability of the Upo wetland.o wetland.

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영산강 하구의 제4기 후기 층서 및 고환경 (Late Quaternary Stratigraphy and Depositional Environment of the Yeongsan River Estuary, Southwestern Korea)

  • 남욱현;김주용;양동윤;홍세선;봉필윤;이윤수;유강민;염종권
    • 자원환경지질
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    • 제36권6호
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    • pp.545-556
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    • 2003
  • 영산강 하구 퇴적물에서 최종빙기 및 현세에 해당하는 길이 18.9m의 시추 퇴적물(심도 20.5∼l.6m)을 획득하였으며, 퇴적물의 조직과 유기질 미화석 분석을 통하여 고환경의 변화를 인지하였다. AMS$^{14}$C 연대측정과 한반도에서의 화분분대 대비에 의하여 퇴적물 연대를 결정하였다. 본 시추 퇴적물에서는 크게 3가지 고환경대를 구분할 수 있었다. (1)최종빙기 퇴적물:주로 하천 퇴적층이며 고토양화 되어 있다. 퇴적 작용과 토양화 작용을 수차례에 걸쳐 받은 것으로 보이며, 고토양의 양상으로 보아 한랭$.$습윤 환경에서 토양화 작용이 진행된 것으로 추측할 수 있다. (2) 현세 초기∼중기 퇴적물:해수면 상승으로 인하여 해수의 영향을 받게 되었으며, 해양성 미화석을 다량 포함하는 점토로 구성된다. (3) 현세 후기 퇴적물: 보다 한랭한 기후를 나타낸다. 이러한 양상은 지역적, 전지구적 환경변화 양상과 일치하는 결과를 보인다.

지구물리 탐사에 의해 발견된 제주도 용암동굴의 특징과 의미 (Characteristics and Implications of Lava Tubes from Geophysical Exploration in Jeju Island)

  • 전용문;기진석;고수연;김련;류춘길
    • 지질공학
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    • 제25권4호
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    • pp.473-484
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    • 2015
  • 제주도에서 기존에 알려진 동굴 이외에 새로운 지하동굴의 존재를 확인하기 위해 제주시 구좌읍 일대에서 지구물리탐사(전기비저항탐사, GPR탐사, ZHF탐사)를 실시하였다. 탐사결과 여러 지점에서 동굴로 추정되는 이상대가 발견되었고, 이상대의 위치와 규모가 일치하는 27개 지점을 선별하여 시추조사를 실시하였다. 그러나 예상과 달리 이상대의 대부분은 용암의 상하부에 형성된 클링커층이거나 용암 사이에 협재된 고토양층이었으며, 5곳에서만 동굴이 발견되었다. 클링커층과 고토양층은 용암과 다른 암석의 물리적 특징으로 인해 이상체로 반응한 것으로 해석된다. 한편 동굴이 확인된 5개 지점 중 2공은 기존에 알려진 용천동굴을 관통하였고, 3공에서 새로운 동굴이 확인되었다. 용천동굴을 관통한 시추공은 시추당시 동굴의 존재가 확인되지 않았던 구간이었으나 용천동굴이 관통됨에 따라 기존 측량도의 오류를 수정하였다. 한편 시추조사로 새롭게 발견된 석회장식 용암동굴은 길이가 약 180 m이며, 상류방향으로 당처물동굴(약 110 m)과 연결되어 있다. 또한 동굴내부에는 용암곡석, 용암제방, 밧줄구조 등이 발달해 있으며, 탄산염 동굴생성물로는 종유관, 종유석, 석순, 석주, 동굴산호 등이 잘 보존되어 있다. 특히 동굴에서 발견되는 탄산염 동굴생성물은 식물 뿌리를 따라 유입된 지표수에 의해 성장하여 독특한 형태를 띠게 된 것으로 추정된다.

화성에서의 고수문학적 활동과 환경변화 (Paleohydrologic Activity and Environmental Change on Mars)

  • ;김경자
    • 한국제4기학회지
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    • 제23권1호
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    • pp.38-41
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    • 2009
  • Results from the most recent decade of Mars' missions to Mars highlight a liquid water and water-ice sculpted landscape. Evidence includes layered sedimentary sequences with weathered outcrops, debris flows, fluvial valleys, alluvial fans, deltas, glacial and periglacial landscapes, and geochemical/mineralogical signatures of aqueous activity, including the formation of sulfates and clays, and the leaching and deposition of elements such as potassium, thorium,and iron. Such evidence indicates weathered zones and possible paleosols in stratigraphic sequences, transport of water and rock materials to sedimentary basins, and the possible formation of extensive transient lakes and possibly transient oceans on Mars. This new evidence is consistent with Viking-era geologic investigations that reported magmatic-driven flooding, ponding to form large water bodies in the northern plains, and transient (tens of thousand of years) hydrological cycles. It may even indicate aqueous activity at present. Both endogenic (magmatic driven) and exogenic (both impact cratering and changes in orbital parameters) have influenced paleohydrologic and environmental change on Mars. Abundance of water and dynamic activity would be decisively important for the possibility of past and present life on Mars.

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한탄강 인근 제4기 고토양층에 대한 토양화학 및 고지자기학적 연구 (Paleomagnetic and Soil Chemical Studies on the Quaternary Paleosol Around the Hantan River)

  • 김복철;황재하;이윤수;이규호;남욱현
    • 자원환경지질
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    • 제37권3호
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    • pp.325-334
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    • 2004
  • 경기도 연천군 청산면(靑山面) 궁평리(宮坪里)의 한탄강변에 발달하는 토양에 대하여 고지자기 분석, X-선 회절분석 (XRD), 토양 분광스펙트럼 분석, 총유기탄소(TOC) 측정을 실시하였다. 이 토양은 비고화 지층으로 제4기 전곡현무암 하부에 놓여있으며, 선캠브리아기의 호상편마암을 기반으로 하고 있으며, 제4기 전곡현무암 분출 직전(271.2$\pm$189.8 ka)에 토양화작용을 받은 고토양층(古土壤: paleosol)이라는 것이 입증되었다. 고토양층은 두 번의 서로 다른 시기에 형성된 켜(layer)로 구성되어 있으며, 퇴적학적, 자기적, 토양 화학적으로 뚜렷하게 구별된다.

부산 두송반도의 다대포층에 발달된 캘크리트복합층 : 성인, 고환경 및 층서적 의미 (Compound Clacrete Deposits from the Dapaepo Formation in Dusong Peninsula, Pusan : Origin, Paleonvironments, and Stratigraphic Implication)

  • 백인성;이준동;김인수;김정진;박종욱
    • 자원환경지질
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    • 제30권3호
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    • pp.263-275
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    • 1997
  • Compound calcrete deposits are recognized from the Dadaepo Formation in Dusong peninsula, Pusan, and their textures, structures, morphology, and stratigraphic distribution are examined. The Dadaepo Formation in study area consists of fluvial plain deposits including floodplain-lake deposits, and the compound calcrete deposits occur above floodplain deposits and below lacustrine deposits. The compound calcrete deposits are composed of nodular to massive (micritic), laminar, nodular, nodular to massive (marly), and marly calcrete deposits. In these calcretes, circumgranular and curved cracks, alveolar structures, fitted peloids, tubular fenestrae with laminar micrite wall (rootlet casts), microstalactic calcite, and tepee structures are observed, which indicates that they are calcic paleosols. Considering their stratigraphic occurrences and pedogenic origin, compound calcrete deposits are interpreted to have formed on distal fluvial plain to palustrine environment by the repetetion of deposition and subsequent calcification due to alternation of lake expansion and contraction. The repetetion of calcrete formation suggests that arid climatic condition was alternated with humid condition in short-term period. Such alternated paleoclimatic condition is similar to those of the Sindong and Hayang groups, and indicates that short-term fluctuations from arid to humid climate were prevailing in overall Gyeongsang Basin. In stratigraphic sense, the compound calcrete deposits can be used as a marker deposit for the correlation of the Dadaepo Formation.

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영덕 일대의 해성단구와 해면변동단구의 대비와 편년 (Correlation and Chronology of the Marine Terraces and Thalassostatic Terraces in the Yeongdeok Coast, South Eastern Korean Peninsula)

  • 최성길;장호
    • 한국지형학회지
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    • 제26권4호
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    • pp.81-96
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    • 2019
  • The Yeongdeok 53m marine terrace (Y53mT), Y43mT, Y33mT, Y24mT, Y19mT and Y11mT distributed along the Yeongdeok coast, southeastern Korean Peninsula are well compared with the thalassostatic terraces of the high terrace 1 (ℓHT1 ; 51m of the relative heights from the river floor), high terrace 2 (ℓHT2 ; 43m), middle terrace 1 (ℓMT1 ; 32m), middle terrace 2 (ℓMT2 ; 25m), lower terrace 1 (ℓLT1 ; 18m) and lower terrace 2 (ℓLT2 ; 10m) respectively, developed along the lower reaches of the Chucksan-cheon and Obo-cheon rivers, judging from the comparison of paleosols (red soils) between the above marine and thalassostatic terraces. Using the Y19mT of the MIS 5e as the key surface, we propose that the terraces of the Y53mT and ℓHT1, Y43mT and ℓHT2, T33mT and ℓMT1, Y24mT and ℓMT2, Y19mT and ℓLT1, and Y11mT and ℓLT2 have been formed at the MIS 11, 9, 7e and 7a (or 7a), 5e and 5a respectively. The red soils have been developed at the Y19mT and ℓLT1 and above them, but not on the Y11mT and ℓLT2 surfaces.

Post LGM Fluvial Environment and Palynological Changes of South Korea

  • Kim, Ju-Yong;Yang, Dong-Yoon;Bong, Pil-Yoon;Nahm, Wook-Hyun;Lee, Heon-Jong;Lee, Yung-Jo;Hong, Sei-Sun;Lee, Jin-Young;Kim, Jin-Wkan;Oh, Keun-Chang
    • 한국제4기학회지
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    • 제17권2호
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    • pp.17-23
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    • 2003
  • In Korea terrestrial fluvial sequences can be used as pedological and sedimentological markers indicating a millenium-scale environmental and climatic changes imprinted in fluvial sub-environments, which in turn are represented by the cyclicity of fluvial sands, backswamp organic muds, and flooding muds intercalations of frostcracked or dessicated brown paleosols. Post LGM and Holocene fluvial and alluvial sedimentary sequences of Korea are formed in such landscapes of coastal, floodplain, backswamp and hillslope areas. Among them, the most outstanding depositional sequences are fluvial gravels, sands and organic mud deposits in coastal, fluvial, or alluvial wetlands. The aim of this study is to explain the sedimentary sequences and palynofloral zones since the last 15,000years, on the basis of organic muds layers intercalated in fluvial sand deposits. Jangheung-ri site of Nam river, Soro-ri site of Miho river, Youngsan rivermouth site in Muan, Oksan-ri site of Hampyeong and Sanggap-ri site of Gochang are illustrated to interpret their sedimentary facies, radiocarbon datings, and palynofloral zonation. Up to the Middle to Late Last Glacial(up to 30-35Ka), old river-bed, flooding, and backswamp sequences contain such arboreal pollens as Pinus, Abies, and Picea, and rich in non-arboreal pollens like Cyperaceae, Gramineae, Ranunculaceae, and Compositae. During the LGM and post-LGM periods until Younger Dryas, vegetation has changes from the sub-alpine conifer forest(up to about 17-11Ka), through the conifer and broad-leaved deciduous forest, or mixed forest (formed during 16,680-13,010yrB.P), to the deciduous and broad-leaved forest (older than 9,500yrB.P). In the Earliest Holocene flooding deposits, fragments of plant roots are abundant and subjected to intensive pedogenic processes. During Holocene, three arboreal pollen zones are identified in the ascending order of strata; Pinus-Colyus zone(mixed conifer and deciduous broad-leaved forest, about up to 10Ka), Alnus-Quercus forest (the cool temperate deciduous broad-leaved forest, about 10Ka-2Ka), and Pinus forest (the conifer forest, about after 2Ka), as examplified in Soro-ri site of Cheonwon county. The palynological zonations of Soro-ri, Oksan-ri, Sanggap-ri, Youngsan estuary, and Gimhae fluvial plain have been recognized as a provisional correlation tool, and zonations based on fluvial backswamp and flooding deposits shows a similar result with those of previous researchers.

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