At its simplest it's like twirling a napkin or piece of paper from the center where alternate edges rise.
If a picture's worth 1000 words, this kind of effect:
There's already a flat spiral example here:
How can I make a flat, spiralled surface?
As I'm envisioning it, for example, the red twirls would be raised.
I've seen comparable examples on cylinders, but not on surfaces (square or circular) - like a pleated dress for example, or a curly cone, but not a flat surface.
Is that enough info?
Tried simple deform and proportional editing, but I keep missing the mark. Maybe they're key to the result or not.