Layers of volcanic ash on the eroding edges of the icecap of an Icelandic volcano. Does it remind you of something by any chance?
Well…? It made me think of van Gogh’s Starry Night. The oil rendering is too bright a contrast but the reed pen version is pale.
And here’s another one
Heavier ash – different erosion pattern…
And altogether different again…
This could be a black and white image of the wood grain in a carving, but isn’t -
These kinda remind me of Gum Tree bark or wasp paper: