• Title/Summary/Keyword: beach sand deposition during postglacial transgression era

Search Result 1, Processing Time 0.015 seconds

The Geomorphic Changes of Sand-Beach Coasts by Human Impact in Byeonsan Peninsula, Southwest Korea (인간간섭에 따른 변산반도 사빈해안의 지형변화)

  • CHOI, Hoon;LEE, Min-Boo
    • Journal of The Geomorphological Association of Korea
    • /
    • v.19 no.3
    • /
    • pp.83-96
    • /
    • 2012
  • The origins of beaches at Byeonsan Peninsular, as a pocket type, are classified to a sand barrier type and wave-cut type. The beaches had developed by the deposition of the silt and clay layers on the 10m height from sea level in the inner bay during climax era of postglacial transgression. At that time, some sands had blown toward the inland hills to form aeolian deposits. After postglacial sea-level stabilization, sometimes, there has been the negative budget of beach materials. Recently, beaches have been transformed by human impact such as construction of Saemangeum sea-wall, especially in the Byeonsan and Gosapo beaches being close to the sea-wall. So the speed of tidal currents become slower and comparatively depositoinal activity stronger. And the level of chemical weathering has been higher. In Byeonsan beach, the ratio of coarse sand decreased with higher ratio of finer materials and by beach erosion dissected runnels developed, running parallel to the coastline. In Gosapo beach, supply of suspended materials are increased through the Garyeok drainage gate, the sands tend to be finer.