ARE CHAOTIC PARTICLE TRAJECTORIES FRACTALS

It is shown that chaotic particle trajectories in a simple model of tw o superposed internal inertia-gravity waves may come under the class o f natural fractals. The fractal dimension is estimated to lie between 1.2 and 1.5, depending on the strength of the perturbation forcing int roduced by the second wave. The significance of the present result is that fractal scaling behaviour of particle paths may arise even before the Eulerian flow becomes turbulent. Implications of the results are discussed from theoretical and experimental viewpoints.