These explore variation of the oscillation frequencies of the various parameters. In particular, the RGB colour components are individually controlled by a sinusoidal amplitude variations when the frequencies and phases associated with each colour selected so that many cycles are required before the pattern repeats.
There is a good deal of trial and error involved in achieving results that achieve some visual interest.
A number of the later figures are sequences in which images are saved at a number of time-points, showing the build up of the figure over many iterations of the algorithm.