沿岸漂移

波浪作用帶動沿岸的沙和粗礫以之字形移動

波浪以傾斜的角度接近海岸

沖流以與盛行風平行的方向衝上岸

回流在重力作用下以直角退離岸邊

The zig-zag movement of sand and shingle along the shore driven by wave action

Waves approach the shore in oblique angle

Swash rush up the shore in a direction parallel to the prevailing wind

Backwash run down the shore at right angles under gravity