태안군 운여 해안의 해안사구체에 대한 퇴적 및 루미네선스 연대측정
The sedimentology and luminescence chronology of a coastal dune sequence at Unyo Beach, T?ean-Gun
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초록
태안군 남부의 안면도에 위치한 운여해수욕장 인근의 해안사구를 대상으로, 일련의 사구퇴적물에 대해별되는데, 상부층은 담황색 모래, 그리고 하부층은 적갈색 모래로 구성되어 있다. 하부층이 적갈색을 띄는 것은 과거 어느 시기에 토양생성작용을 받은 결과이며, 이는 매몰된 고토양임을 시사한다. 이들 상·하부 퇴적층의 시료에 대해 입도분석과 주사전자현미경 분석을 시행하였는데, 그 결과 입도분포, 형태, 표면조직 특성 등이 모두 유사음을 의미한다. 한편, 루미네선스 연대측정을 통해 하부 모래층은 약 5~7ka에 형성된 것으로 밝혀졌는데, 이는 홀로세의 기후 최적기에 해당하는 시기이다. 반면, 상부 모래층에서 얻은 시료는 약 70~90년으로 밝혀졌다. 이러한결과는 태안 지역의 적갈색 퇴적층이 지난 최종간빙기 또는 그 이전에 형성되었을 것이라는 종전의 인식에 상반된 기간이 있었으며, 그 이후 다시금 취식과 퇴적이 이루어지면서 상부층 모래가 퇴적된 것으로 추정된다.
Abstract
A sequence of aeolian sediments within a coastal dune structure located at Unyo Beach in southernTaean-Gun has been investigated using sedimentological and luminescence dating techniques. The sedimentarysuccession comprises a lower sand unit, reddish in color in the upper part, which is overlain by a buff colored sand unit.The red coloration of the lower unit is the result of pedogenic processes that occurred at some stage in the past and,thus, represents a buried soil. Analysis by granulometry and SEM shows that sand grains from the two depositional unitshave similar size distribution, shape and surface textural properties and these are consistent with an aeolian origin.Luminescence dating yields ages in the range ca. 5 - 7 ka for the lower sand unit, which coincides with the ClimaticOptimum. A sample from the upper sand unit is dated at ca 70 - 90 yrs. Hence, contrary to what has been a commonpractice, red sands within the Taean-Gun area cannot always be described as sediments deposited during the lastinterglacial. The buried soil in the lower unit points to a period of stability of the dune surface some time between ca. 5 kaand 90 yr ago. The resumption of deposition after the hiatus is probably the result of blowout development in the upwinddirection.
참고문헌 (24)
- Arens, "Patterns of sand transport on vegetated foredunes", pp.339~350 (1996)
- Birkeland, "Soils and Geomorphology", pp.430~ (1999), Oxford Univ Press
- Blott, "A grain size distribution and statistics package for the analysis of unconsolidated sediments", pp.1237~1248 (2001)
- A, "Advances in luminescence instrument systems", pp.523~528 (2000)
- Folk, "a study in the significance of grain size parameters Journal of Sedimentary Petrology", pp.3~26 (1957)
- Goudie, "The shape of desert sand dune grains Journal of Arid Environments"
- Kahng T, "The origin of coastal dunes in the Chungcheongnam-do Journal of the Korean Geographical Society", pp.505~517 (2003)
- Kahng, "Beach and sand dune development along the coastline of the Chungcheong-Namdo Province Journal of Korean Earth Science Society", pp.568~577 (2003)
- and Marshall, "Analysis of Sedimentary and Volcanic Clasts", pp.346~ (1987), Van Nostrand Reinhold Company
- Kwon, "Coastal geomorphology of T？aean and Anmyun area Journal of Education", pp.261~287 (1981), Korea Univ
- Mahaney, "Atlas of Sand Grain Surface Textures and Applications", pp.237~ (2002), Oxford Univ
- McKeever, "Thermoluminescence Dosimetry Materials: Properties and Uses", pp.202~ (1995)
- McManus, "Techniques in Sedimentology", pp.63~85 (1988)
- Kim, "The development and luminescence chronology of a coastal dune from the Shindu dunefield Journal of the Korean Geographical Society", pp.269~282 (2004)
- Murray, "Luminescence dating of quartz using an improved singlealiquot regenerative-dose protocol", pp.57~73 (2000)
- Murray, "potential for improvements in reliability", pp.377~381 (2003)
- Murray, "The effects of disequilibria in the uranium and thorium decay chains on burial dose rates in fluvial sediments", pp.751~760 (1996)
- Park, "A Study on the Morphology of the Coastal Dunes of the Western Coast of Korea Journal of Geography", pp.1~10 (1979), Seoul National Univ
- Park, "Study of dune-reddening at Cheonri-po" (1987), Seoul National Univ
- Retallak, "Soils of the past An Introduction to Palaeopedology", pp.404~ (2001), Blackwell Science
- Seo, "Morphological Changes and Sediment Budget of Coastal Dunefields in Shinduri" (2001), Seoul National Univ Unpublished Ph
- Williams, "Analysis of barrier island and surface sediments by scanning electron microscopy", pp.101~118 (1989)
- Zimmerman, "Thermoluminescence dating using fine grains from pottery", pp.29~52 (1971)
- Kwon, H. J.,, "Coastal erosion in western coast of Korea"