Simulations of 137Cs distribution in lake sediment cores are presented for slow and rapid mixing processes, for different mixing layers, and for different sampling thicknesses. A parameter characterizing the profile distribution is introduced. Interpretation of the 137Cs profiles of seven alpine lakes is given using those simulations leading to an estimate of the sedimentation rate, the type of mixing and the thickness of the mixing layer. These parameters are compared with those obtained independently from 210Pb profiles in three of the lakes. Agreement is satisfactory. The lakes we studied have similar features. In most cases the lakes have mixing which can be approximated by a rapid diffusion process, sedimentation rate of the order of 0.01 g cm-2 yr-1, and a mixing layer of the order of 2--4 cm. ¿ American Geophysical Union 1989