MORPHOLOGICAL CHANGES OF SHORELINE AND OFFSHOREBARS ALONG TOTTORI COAST

摘要

The present study deals with a short-term change of a coast line and a sand bar systemalong Tottori coast. The observations have been made applying Argus method. Thecoast line and sand bars show year around change feature. In late autumn, the shore lineand inner bar are very smooth and straight. In winter, high waves bring cusping featureon the shore line and the concavo-convex feature on the inner bar with offshoreconvexity at bay and shoreward concavo at horn locations. These features on the shoreline and the inner bar are opposite in phase. Rip channels develop from the cusp bay.From spring to autumn, these features gradually diminish. While an outer bar showscrescentic feature with an offshore convexity all year round. Its amplitude slightlyreduces in winter and extends from spring to autumn. Change of these features, beachcusp and convexity of inner and outer bars, seems quite different from existing bar statemodels.