Looks like Octagon granny squares sewn together.
Anelma flower socks paid pattern on ravelry
Ravelry: Ruususet-sukkaset pattern by Sinikka Nissi - If only I could knit like this!
Talia pattern by Rachel Coopey. I like the subtle color shifts in these stranded socks! Lots of visual interest without jarring one's eyes!
Ravelry: Nettle Essence Svensk version pattern by Monica Hellberg by dianna