People in the swimming pool industry call the patterns simply
"ripples" but IMHO that's a misnomer. I say ripples on the
top of the water explain the caustics on the bottom.
In any case, there's more to the story. The /brightest/ parts
of the pattern are presumably caustics, in the strictest sense
... but is there perhaps a nice name for the pattern as a whole?
Sparkles? Spangles? ?????????